AU2004203658B2 - A replenishable one time use camera system with recapping mechanism - Google Patents

Description

CLAIMS:

1. A pagewidth ink jet printhead assembly comprising a pagewidth ink jet printhead and a recapping mechanism for recapping the print head, the recapping mechanism comprising: a first stationary ferrous arm; a solenoid coil wrappendaround a portion of said ferrous arm; a second moveable arm located substantially adjacent said first arm and biased towards said print head; and a series of membranes attached to said second moveable arm, said membranes sealing said print head when in a non printing position; wherein said solenoid, when activated, causes said moveable ann to move away from the surface of said print head structure sufficiently to allow paper or film to be inserted between said membranes and said print head structure for the printing of ink thereon.

2. A print head assembly as claimed in claim 1 wherein said membranes are resiliently collapsible against the surface of said print head structure.

3. A print head assembly as claimed in claim I or claim 2 wherein said solenoid comprises an elongated winding of a current carrying wire which is wrapped around a protruding portion of said first arm, said elongated winding being substantially the length of said print head structure.

4. A print head assembly as claimed in any previous claim wherein said membranes comprise two mutually opposed elastomer trips running substantially the length of the ink jetting portions of said print head structure so as to surround said ink jetting portions, A print head assembly as claimed in any previous claim wherein said second movable an is biased against the surface of said print head structure.

6. A print head assembly as claimed in any previous claim wherein said solenoid is activated to move said second arn closely adjacent said first ann with a first level of current and said solenoid is retained whilst printing closely adjacent said first arm with a second substantially lower level of current.

7, A print head assembly as claimed in any previous claim wherein said assembly is utilized in a hand held camera device.

a print head mechanism for printing out pictures on demand. The ink supply cartridge 42 includes a side aluminium strip 43 which is provided as a shear strip to assist in cutting images from a pater roll.

A dial mechanism 44 is provided for indicating the number of "prints left". The dial mechanism 44 is snap fitted through a corresponding mating portion 46 so as to be freely rotatable, As shown in Fig. 6, the print head includes a flexible PCB strip 47 which interconnects with the print head and provides for control of the print head. The interconnection between the Flex PCB strip and an image sensor and print head chip can be via Tape Automated Bonding (TAB) Strips 51, 58. A moulded aspherical lens and aperture shim (Fig. 5) is also provided for imaging an image onto the surface of the image sensor chip normally located within eavity 53 and a light box module or hood 52 is provided for snap fitting over the cavity 53 so as to provide for proper light control.

A series of decoupling capacitors eg. 34 can also be provided. Further a plug 45 (Fig. 7) is provided for re-plugging ink holes after refilling. A series of guide prongs eg, 55-57 are further provided for guiding the flexible PCB strip 47.

The ink supply mechanism 40 interacts with a platten unit which guides print media under a printhead located in the ink supply mechanism. Fig. 8 shows an exploded view of the platten unit 60, while Figs. 9 and 10 show assembled views of the platten unit. The platten unit 60 includes a first pinch roller 61 which is snap fitted to one side of a platten base 62. Attached to a second side of the platten base 62 is a cutting mechanism 63 which traverses the platten by means of a rod 64 having a screwed thread which is rotated by means of cogged wheel 65 which is also fitted to the platten 62.

The screwed thread engages a block 67 which includes a cutting wheel 68 fistened vi a a fastener 69. Also mounted to the block 67 is a counter actuator which includes a prong 7 1 The prong 71 acts to rotate the dial mechanism 44 of Fig. 6 un t here t u rn n l 1 i E 11 liiifil I ii 1 DI ID aan 1 -11 1 111-- I It can be seen that the preferred embodiment provides for a simple and inexpensive means of re-capping a printhead through the utilisation of a solenoid type device having a long rectangular form. Further, the preferred embodiment utilises minimal power in that currents are only required whilst the device is operational and additionally, only a low keeper current is required whilst the printhead is printing.

Turning next to Fig. 13 and Fig. 14, Fig. 13 illustrates an exploded perspective of the ink supply cartridge 42 whilst Fig. 14 illustrates a close up sectional view of a bottom of the ink supply cartridge with the printhead unit in place.

The ink supply cartridge 42 is based around a pagewidth printhead 102 which comprises a long slither of silicon having a series of holes etched on the back surface for the supply of ink to a front surface of the silicon wafer for subsequent ejection via a micro electro mechanical system. The form of ejectio an be many different forms such as those set out in the relevant provisional patent specifications of the attached appendix. In particular, the ink jet printing system set out in the provisional patent specification entitled "An Image Creation Method and Apparatus (138)" filed concurrently herewith is highly suitable. Of Course, many other inkjet technologies, a referred to the attached appendix, can also be utilised when constructing a printhead unit 102. The fimdamental requirement of the ink supply cartridge 42 being the supply of ink to a series of colour chamies etched through the back surface of the printhead 102. In the description of the preferred embodiment, it is assumed that a three colour printing process is to be utilised so as to provide full colour picture output. Hence, the print supply unit 42 includes three ink supply reservoirs being a cyan reservoir 104, a magenta reservoir 105 and a yellow reservoir 106. Each of these reservoirs is required to store ink and includes a corresponding sponge type material 107 109 which assists in stabilising ink within the corresponding ink channel and therefore preventing the ink from sloshing back and forth when the printhead is utilised in a handheld camera system. The reservoirs 104, 105, 106 are formed through the mating of first exterior plastic piece 110 mating with the second base piece il 1.

At first end of the base piece i includes a series of air inlet 113 115. The air inlet leads to a corresponding winding channel which is hydrophobically treated so as to act as an ink repellent and therefore repel any ink that may flow along the air inlet channel. The air inlet channel firther takes a convoluted path firther assisting in resisting any ink flow out of the chambers 104 -106. An adhesive tape portion 117 is provided for sealing the channels within end portion 118.

At the top end, there is included a series ofrefill holes for refilling corresponding ink supply chambers 104, 105, 106. A plug 121 is provided for sealing the refill holes.

Turning now to Fig. 14, there is illustrated a close up perspective view, partly in section through the ink supply cartridge 42 of Fig. 13 when formed as a unit. The ink supply cartridge includes the three colour ink reservoirs 104, 105, 106 which supply ink to different portions of the back surface of printhead 102 which includes a series of apertures 128 defined therein for carriage of the ink to the front surface.

The ink supply unit includes two guide walls 124, 125 which separate the various ink chambers and are tapered into an end portion abutting the surface of the printhead 102. The guide walls are further mechanically supported and regular spaces by a block portions eg. 126 which are placed at regular intervals along the length of the printhead supply unit. The block portions 126 leaving space at portions close to the back ofprinthead 102 for the flow of ink around the back surface thereof,. The printhead-supply unit is preferably formed from a-multi-part plastic injection mould and the mould pieces eg. 10, 11 (Fig. 1) snap together around the sponge pieces 107, 109. Subsequently,.a syringe type device can be inserted in the ink refill holes and the ink reservoirs filled with ink with the air flowing out of the air outlets 113 -115.

Subsequently, the adhesive tape portion 117 and plug 121 are attached and the printhead td ted for operation capabilities.

Subsequently, the ink supply cartridge 42 can be readily removed for refilling by means of removing the ink supply cartridge, performing a washing cycle, and then utilising the holes for the insertion of a refill syringe filled with ink for refilling the ink chamber before returning the ink supply cartridge 42 to a camera.

-11 Turning now to Fig. 15, there is shown an example layout of the Image Capture aid Processing Chip (ICP) 48.

The Image Capture and Processing Chip 48 provides most of the electronic functionality of the camera with the exception of the print head chip. The chip 48 is a highly integrated system. It combines CMOS image sensing, analog to digital conversion, digital image processing, DRAM storage, ROM, and miscellaneous control functions in a single chip.

The chip is estimated to be around 32 mm using a leading edge 0 18 micron CMOS/DIRANlAPS process. The chip size and cost can scale somewhat with Moore's law, but is dominated by a CMOS active pixel sensor array 201, so scaling is limited as die sensor pixels approach the diffraction limit.

The ICP 48 includes CMOS logic, a CMOS image sensor, DRAM, and analog circuitry. A very small amount of flash memory or other non-volatile memory is also preferably included for protection against reverse engineering.

Alternatively, the ICP can readily be divided into two chips: one for the CMOS imaging array, and the other for the remaining circuitry. The cost of this two chip solution should not be significantly different than the single chip ICP, as the extra cost of packaging and bond-pad area is somewhat cancelled by the reduced total wafer area requiring the colour filter fabrication steps.

The ICP preferably contains the following functions: Function megapixel image sensor Analog Signal Processors Image sensor column decoders Image sensor row decoders Analogue to digital Conversion (ADC) Column ADC's Auto exposure 12Mbits of DRAM DRAM Address Generator Colour interpolator Convolver Colour ALU Halftone matrix ROM Digital halftoning Print head interface 8 bit CPU core Program ROM Flash memory Scratchpad SRAM Parallel interface (8bit) Motor drive transistors Clock PLL JTAG test interface Test circuits Busses Bond pads -12- The CPU, DRAM, image sensor, ROM, Flash memory, Parallel interface, JTAG interface and ADC can be vendor supplied cores. The ICP is intended to run on 1.5V to minimise power consumption and allow convenient operation from two AA type battery cells.

illustrates a ayout of the ICP 48. The ICP 48 is dominated by the imaging array 201, which consumes around 80% of the chip area. The imaging array is a CMOS 4 transistor active pixel design with a resolution of 1,500 x 1,000. The array can be divided into the conventional configuation, with two green pixels, one red pixel, and one blue pixel in each pixel group. There are 750 x 500 pixes groups in the imaging array.

The latest advances in the field of image sensing and CMOS image sensing in particular can be found in the October, 1997 issue of IEEE Transactions on Electron Devices and, in particular, pages 1689 to 1968. Further, a specific implementation similar to that disclosed in the present application is disclosed in Wong et, al, "CMOS Active Pixel Image Sensors Fabricated Using a l.8V, 0.25gm CMOS Technology", IEDM 1996, page 915.

The imaging array uses a 4 transistor active pixel design of a standard configuration. To minimise chip area and therefore cost, the image sensor pixels should be as small as feasible with the technology available. With a four transistor cell, the typical pixel size scales as 20 times the lithographic feature size. This allows a minimum pixel area of around 3.6nm x 3.6am. However, the photosite must be substantially above the diffraction limit of the lens. It is also advantageous to have a square photosite, to maximise the margin over the diffraction limited in both horizontal and vertical directions. in this case, the photosite can be specified as 2.5,im x 2.5gm, The photosite can be a photogate, pinned photodiode, charge modulation device, or other sensor.

'The four transistors are packed as an shape, rather than a rectangular region, to allow both the pixel and the photsite to be square. This reduces the transistor packing density slightly, increasing pixel size. However, the advantage in avoiding the diffraction limit is greater than the small decrease in packing density.

T'he transistors also have a gate length which is longer than the minimum for the process technology. These have been increased from a drawn length of 0.18 micron to a drawn length of 0.36 micron. This is to improve the transistor matching by making the variations in gate length represent a smaller proportion of the total gate length.

The extra gate length, and the shaped packing, mean that the transistors use more area than the minimum for the technology. Normally, around 81pm' would be required for rectangular packing. Preferably, 9,75p m has been allowed for the transistors.

The total area for each pixel is 16grm, resulting from a pixel size of 4pm x 4pm. With a reslotution of 1,500 x 1,000, the area of the imaging array 10i is 6,000gm x 4,000.tm, or 24nmni a The presence of a colour image sensor on the chip affects the process required in two major ways: the CMOS fabrication process should be optimised to minimise dark current Colour filters are required. These can be fabricated using dyed photosensitive polyimides, reultiing in an added process complexity of three spin coatings, three photolithographic steps, three development steps, and three hardbakes.

There are 15,00 analog signal processors (ASPs) 205, one for each of the columns of the sensor. The ASPs amplify the signal, provide a dark current-reference, sample and hold the signal, and suppress the fixed pattern noise There are 375 analog to digital converters 206, one for each four columns of the sensor array. These may be delta-sigma or successive approximation type ADC's A row of low column ADC's are used to reduce the conversion speed required, and the amount of analogue signal degradation incurred before the signal is converted to digital. This also eliminated the hot spot (affecting local dark current) and the substrate coupled noise that would occur if a single high speed ADC was used. Each ADC also has two four bit DAC's which trim the offset and scale of the ADC to further reduce FPN variations between columns. These DAC's are controlled by data stored in flash memory during chip testing, -13- The column select logic 204 is a 1:1500 decoder which enables the appropriate digital output of the ADC's onto the output bus. As each ADC is shared by four columns, the least significant two bits of the row select control 4 input analog multiplexers.

A row decoder 207 is a 1:1000 decoder which enables the appropriate row of the active pixel sensor array. This S selects which of the !000 rows of the imaging array is connected to analog signal processors, As the rows are always accessed in sequence, the row select logic can be implemented as a shift register.

An auto exposure system 208 adjusts the reference voltage of the ADC 205 in response to the maximum intensity sensed during the previous frame period. Data from the green pixels is passed through a digital peak detector.

The peak value of the image frame period before capture (the reference frame) is provided to a digital to analogue 1 0 converter (DAC), which generates the global reference voltage for the column ADCs. The peak detector is reset at the beginning of the reference frame. The minimum and maximum values of the three RGB colour components are also collected for colour correction.

The second largest section of the chip is consumed by a DRAM 210 used to hold the image. To store the 1,500 x 1,000 image from the sensor without compression, 1.5 Mbytes of DRAM 210 are required. This equals 12 Mbits, or slightly less than 5% of a 256 Mbit DRAM. The DRAM technology assumed is of the 256 Mbit generation implemented using 0.18pm CMOS.

Using a standard 8F cell, the area taken by the memory array is 3.1 lnnm. When row decoders, column sensors, redundancy, and other factors are taken into account, the DRAM requires around 4mml.

This DRAM 210 can be mostly eliminated if analog storage of the image signal can be accurately maintained in the CMOS imaging array for the two seconds required to print the photo. However, digital storage of the image is preferable as it is maintained withou degradation, is insensitive to noise, and allows copies of the photo to be printed considerably later.

A DRAM address generator 211 provides the write and read addresses to the DRAM 210. Under normal operation, the write address is determined by the order of the data read from the CMOS image sensor 201. This will typically be a simple raster format. However, the data can be read from the sensor 201 in any order, if matching write addresses to the DRAM are generated. The read order from the DRAM 210 will normally simply match the requirements of a colour interpolator and the print head. As the cyan, magenta, and yellow rows of the print head are necessarily offset by a few pixels to allow space for nozzle actuators, the colours are not read from the DRAM simultaneously. However, there is plenty of time to read all of the data from the DRAM many times during the prnining process. This capability is used to eliminate the need for FIFOs in the print head interface, thereby saving chip area. All three RGB image components can be read from the DRAM each time colour data is required. This allows a colour space convere to provide a more sophisticated conversion than a simple linear RGB to CMY conversion.

Also, to allow two dimensional filtering of the image data without requiring line buffers, data is re-read from the DRAM array.

The address generator may also implement image effects in certain models of camera. For example, passport photos are generated by a manipulation of the read addresses to the DRAM. Also, image framing effects (where the central image is reduced)-image warps, and kaleidoscopic effects can all be generated by manipulating the read addresses of the DRAM.

While the address generator 211 may be implemented with substantial complexity if effects are built into the standard chip, the chip area required for the address generator is small, as it consists only of address counters and a moderate amount of random logic.

A colour interpolator 214 converts the interleaved patter of red, 2 x green, and blue pixels into RGB pixels. It consists of three 8 bit adders and associated registers. The divisions are by either 2 (for green) or 4 (for red and blue) so they can be implemented as fixed shifts in the output connections of the adders.

-14- A convoiver 215 is provided as a sharpening filter which applies a small convolution kernel (5 x 5) to the red, green, and blue planes of the image. The convolution kernel for the green plane is different from that of the red and blue planes, as green has twice as many samples. The sharpening filter has five functions: To improve the colour interpolation from the linear interpolation provided by the colour interpolator, to a close approximation of a since interpolation.

To compensate for the image "softening" which occurs during digitisation.

To adjust the image sharpness to match average consumer preferences, which are typically for the image to be slightly sharper than reality. As the single use camera is intended as a consumer product, and not a professional photographic products, the processing can match the most popular settings, rather than the most accurate.

To suppress the sharpening of high frequency (individual pixel) noise. The finction is similar to the "mnsharp mask" process.

To antialias Image Warping.

These functions are all combined into a single convolution matrix. As the pixel rate is low (less than I Mpixel per second) the total number of multiplies required for the thre colour channels is 56 million multiplies per second. This can be provided by a single multiplier. Fifty bytes of coefficient ROM are also required.

A colour ALU 113 combines the functions of colour compensation and colour space conversion into the one matrix multiplication, which is applied to every pixel of the frame, As with sharpening, the colour correction should match the most popular settings, rather then the most accurate.

A colour compensation circuit of the colour ALU provides compensation for the lighting of the photo. The vast majority of photographs are substantially improved by a simple colour compensation, which independently normalises the contrast and brightness of the three colour components.

A colour look-up table (CLUT) 212 is provided for each colour component. These are three separate 256 x 8 SRAMs, requiring a total of 6,144 bits. The CLUTs are used as part of the colour correction process. They are also used for colour special effects, such as stochastically selected "wild colour" effects.

A colour space conversion system of the colour ALU converts from the ROB colour space of the image sensor to the CMY colour space of the printer. The simplest conversion is a i's complement of the RGB data. However, this simple conversion assumes perfect linearity of both colour spaces, and perfect dye spectra for both the colour filters of the image sensor, and the ink dyes. At the other extreme is a tri-linear interpolation of a sampled three dimensional arbitrary transform table. This can effectively match any non-linearity or differences in either colour space. Such a system is usually necessary to obtain good colour space conversion when the print engine is a colour electrophotographic.

However, since the non-linearity of a halfioned ink jet output is very small, a simpler system can be used, A simple matrix multiply can provide excellent results. This requires nine multiplies and six additions per contone pixel.

However, since the contone pixel rate is low (less than I Mpixelsec) these operations can share a single multiplier and adder. The multiplier and adder are used in a colour ALU which is shared with the colour compensation function.

Digital halfioning can be performed as a dispersed dot ordered dither using a stochastic optimised dither cell. -A halftone matrix ROM 116 is provided for storing dither cell coefficients. A dither cell size of 32 x 32 is adequate to ensure that the cell repeat cycle is not visible. The three colours cyan, magenta, and yellow are all dithered using the same cell, to ensure maximum co-positioning of the ink.dots. This minimises "muddying" of the mid-tones which results from bleed of dyes from one dot to adjacent dots while still wet. The total ROM size required is I KByte, as the one ROM shared by the halftoning units for each of the three colours.

The digital halftoning used is dispersed dot ordered dither with tochastic optimised dither matrix. While dithering does not produce an image quite as "sharp" as error diffusion, it does produce a more accurate image with fewer artefacts. The image sharpening produced by error diffusion is artificial, and less controllable and accurate than "u'sharp mask" filtering performed in the contone domain. The high print resolution (1,600 dpi x 1,600 dpi) results in excellent quality when using a well formed stochastic dither matrix.

Digital halftoning is performed by a digital halftoning unit 217 using a simple comparison between the contone information from the DRAM 210 and the contents of the dither matrix 216. During the halftone process, the resolution of the image is changed from the 250 dpi of the captured contone image to the 1,600 dpi of the printed image. Each contone pixel is converted to an average of 40.96 halftone dots, The ICP incorporates a 16 bit microcontroller CPU core 219 to run the miscellaneous camera functions, such as reading the buttons, controlling the motor and solenoids, setting up the hardware, and authenticating the refill station. The processing power required by the CPU is very modest, and a wide variety of processor cores can be used. As.the entire CPU program is run from a small ROM 220. Program compatibility between camera versions is not important, as no external programs are run. A 2 Mbit (256 Kbyte) program and data ROM 220 is included on chip. Most of this ROM space is allocated to data for outline graphics and fonts for specialty cameras. The program requirements are minor. The single most complex task is the encrypted authentication of the refill station. The ROM requires a single transistor per bit.

A Flash memory 221 may be used to store a 128 bit authentication code. This provides higher security than storage of the authentication code in ROM, as reverse engineering can be made essentially impossible. The Flash memory is completely covered by third level metal, making the data impossible to extract using scanning probe microscopes or electron beams. The authentication code is stored in the chip when manufactured. At least two other Flash bits are required for the authentication process: a bit which locks out reprogramming of the authentication code, and a bit which indicates that the camera has been refilled by an authenticated refill station. The flash memory can also be used to store FPN correction data for the imaging array. Additionally, a phase locked loop resealing parameter is stored provided for scaling the clocking cycle to an appropriated correct time. The clock frequency does not require crystal accuracy since no date functions are provided. To eliminate the cost of a crystal, an on-chip oscillator with a phase locked loop 124 is used.

As the frequency of an on-chip oscillator is highly variable from chip to chip, the frequency ratio of the oscillator to the PLL is digitally trimmed during initial testing. The value is stored in Flash memory 121. This allows the clock PLL to control the inkjet heater pulse width with sufficient accuracy.

A scratchpad SRAM is a small static RAM 222 with a 6T cell. The scratch pad provided temporary memory for the 16 bit CPU, 1024 bytes is adequate.

A print head interface 223 formats the data correctly for the print head. The print head interface also provides all of the timing signals required by the print head. These timing signals may vary depending upon temperature, the number of dots printed simultaneously, the print medium in the print roll, and the dye density of the ink in the print roll.

The following is a table of external connections to the print head surface: Connection Function Pins Databits[0-7] Independent serial data to the eight segnents of the print head. 8 BitClock Main data clock for the print head. 1 ColourEnable[0-2] Independent enable signals for the CMY actuators, allowing 3 different pulse times for each colour.

-16-- Banknable{0- Allows either simutaneous or interleaved actuation of two banks of 2 nozzles. This allows two different print speedipower consumption tradeoffs.

NozzleSelect(0-4] Selects one of 32 banks of nozzles for simultaneous actuation. ParalielXferClock Loads the parallel transfer register with the data from the shift registers. I Total The print head utilised is composed of eight identical segments, each 1.25cm long. There is no connection between the segments on the print head chip. Any connections required are made in the external TAB bonding film, which is double sided. The division into eight identical segments is to simplify lithography using wafer steppers. The segment width of ,25cm fits easily into a stepper field. As the print head chip is long and narrow (10cm x 0.3mm), the stepper field contains a single segment of 32 print head chips. The stepper field is therefore 1,25cm x 16cm., An average of four complete print heads are patterned in each wafer step.

A single BitClock output line connects to all 8 segments on the print head. The 8 DataBits lines lead one to each segment, and are clocked in to the 8 segments on the print head simultaneously (on a BitClock pulse). For example, dot 0 is transferred to segment, dot 750 is transferred to segment;, dot 1500 to segment 2 etc simultaneously.

The ParallelXferClock is connected to each of the 8 segments on the print head, so that on a single pulse, all segments transfer their bits at the same time.

The NozzleSelect, BankEnable and ColorEnable lines are connected to each of the 8 segments, allowing the print head interface to independently control the duration of the cyan, magenta, and yellow nozle energizing pulses. Registers in the Print Head Interface allow the accurate specification of the pulse duration between 0 and 6 ms, with a typical duration of 2 ms to 3 ms.

A parallel interface 125 connects the ICP to individual static electrical signals. The CPU is able to control each of these connections as memory mapped IO via a low speed bus.

The following is a table of connections to the parallel interface: Connection Direction ins Paper transport stepper motor Output 4 Capping solenoid Output 1 Copy LED Output 1 Photo button Input 1 Copy button Input 1 Total 8 A serial interface is also included to allow authentication of the refill station. This is included to ensure that the cameras are only refilled with paper and ink at authorized refill stations, thus preventing inferior quality refill industry from occurring. The camera must authenticate the refill station, rather than the other way around. The.

-17secure protocol is communicated to the refill station via a serial data connection. Contact can be made to four gold plated spots on the iCP/print head TAB by the refill station as the new ink is injected into the print head.

Seven high current drive transistors eg. 227 are required Four are for the four phases of the main stepper motor two are for the guillotine motor, and the remaining transistor is to drive the capping solenoid. These transistors are allocated 20,000 square microns (600,000 F) each. As the transistors are driving highly inductive loads, they must either be turned off slowly, or be provided with a high level of back EMF protection. If adequate back EMF protection cannot be provided using the chip process chosen, then external discrete transistors should be used. The transistors are never driven at the same time as the image sensor is used. This is to avoid voltage fluctuations and hot spots affecting the image quality. Further, the transistors are located as far away from the sensor as possible.

A standard JTAG (Joint Test Action Group) interface 228 is included in the ICP for testing purposes and for interrogation by the refill station. Due to the complexity of the chip, a variety of testing techniques are required, including BIST (Built In Self Test) and functional block isolation. An overhead of 10% in chip area is assumed for chip testing circuitry for the random logic portions. The overhead for the large arrays them image sensor and the DRAM is smaller.

The JTAG interface is also used for authentication of the refill station. This is included to ensure that the cameras are only refilled with quality paper and ink at a properly constructed refill station, thus preventing inferior quality refills from occurring. The camnera must authenticate the refill station, rather than vice versa. The secure protocol is communicated to the refill station during the automated test procedure. Contact is made to four gold plated spots on the ICP/print head TAB by the refill station as the new ink is injected into the print head.

Fig. 16 illustrates rear view of the next step in the construction process whilst Fig. 17 illustrates a front camera view, Turning now to Fig. 16, the assembly of the camera system proceeds via first assembling the ink supply mechanism 40. The flex PCB is intercomnected with batteries only one 84 of which is shown, which are inserted in the middle portion of a print roll 85 which is wrapped around a plastic former 86. An end cap 89 is provided at the other end of the print roll 85 so as to fasten the print roll and batteries firmly to the ink supply mechanism.

The solenoid coil is interconnected (not shown) to interconnects 97, 98 (Fig. 8) which include leaf spring ends for interconnection with electrical contacts on the Flex PCB so as to provide for electrical control of the solenoid.

Turning now to Figs. 17 -19 the next step in the construction process is the insertion of the relevant gear chains into the side of the camera chassis. Fig. 17 illustrates a front camera view, Fig. 18 illustrates a back side view and Fig. 19 also illustrates a back side view. The first gear chain comprising gear wheels 22, 23 are utilised for driving the guillotine blade with the gear wheel 23 engaging the gear wheel 65 of Fig. 8. The second gear chain comprising gear wheels 24, and 26 engage one end of the print roller 61 of Fig. As best indicated in Fig. 18, the gear wheels mate with corresponding buttons on the surface of the chassis with the gear wheel 26 being snap fitted into corresponding mating hole 27, Next, as illustrated in Fig. 20, the assembled platten unit is then inserted between the print roll 85 and aluminium cutting blade 43.

Turning now to Fig. 2 1 by way of illumination, there is illustrated the electrically interactive components of the camera system. As noted previously, the components are based around a Flex PCB board and include a TAB film 58 which interconnects the printhead 102 with the image sensor and processing chip 51. Power is supplied by two AA type batteries 83, 84 and a paper drive stepper motor 16 is provided in addition to a rotary guillotine motor An optical element 31 is provided for snapping into a top portion of the chassis 12. The optical element 31 includes portions defining an optical view finder 32, 33 which are slotted into mating portions 35, 36 in view finder channel 37. Also provided in the optical element 31 is a lensing system 38 for magnification of the prints left number in addition to an optical pipe element 39 for piping light from the LED 5 for external display.

-18- Turning next to Fig. 22, the assembled unit 90 is then inserted into a front outer case 91 which includes button 4 for activation of printouts.

Turning now to Fig. 23, next, the unit 92 is provided with a snap-on back cover 93 which includes a slot 6 and copy print button 7. A wrapper label containing instructions and advertising (not shown) is then wrapped around the outer surface of the camera system and pinch clamped to the cover by means of clamp strip 96 which can comprise a flexible plastic or rubber strip.

Subsequently, the preferred embodiment is ready for use as a one time use camera system that provides for instant output images on demand. It will be evident that the preferred embodiment further provides for a refillable camera system. A used camera can be collected and its outer plastic cases removed and recycled. A new paper roll and batteries can be added and the ink cartridge refilled. A series of automatic test routines can then be carried out to ensure that the printer is properly operational. Further, in order to ensure only authorised refills are conducted so as to enhance quality, routines in the on-chip program ROM can be executed such that the camera authenticates the refilling station using a secure protocol. Upon authentication, the camera can reset an internal paper count and an external case can be fitted on the camera system with a new outer label. Subsequent packing and shipping can then take place.

It will be further readily evident to those skilled in the art that the program ROM can be modified so as to allow for a variety of digital processing routines. In addition to the digitally enhanced photographs optimised for mainstream consumer preferences, various other models can readily be provided through mere re-progranuning of the program ROM.

For example, a sepia classic old fashion style output can be provided through a remapping of the colour mapping function.

A further alternative is to provide for black and white outputs again through a suitable colour remapping algorithm.

Minimumless colour can also be provided to add a touch of colour to black and white prints to produce the effect that was traditionally used to colourize black and white photographs. Further, passport photo output can be provided through suitable address remappings within the address generators. Further, edge filters can be utilised as is known in the field of image processing to produce sketched art styles. Further, classic wedding borders and designs can be placed around an output image in addition to the provision of relevant clip arts. For examppe, a wedding style camera might be provided.

Further, a panoramic mode can be provided so as to output the well known panoramic format of images. Further, a postcard style output can be provided through the printing of postcards including postage on the back of a print roll surface. Further, clip arts can be provided for special events such as Holoween, Christmas etc. Further, kaleidoscopic effects can be provided through address remappings and wild colour effects can be provided through remapping of the colour look-up table. Many other forms of special event cameras can be provided for example, cameras dedicated to the Olympics, movie tie-ins, advertising and other special events.

The operational mode of the camera can be prograummed so that upon the depressing of the take photo a first image is sampled by the sensor array to determine irrelevant parameters. Next a second image is again captured which is utilised for the output. The captured image is then manipulated in accordance with any special requirements before being initially output on the paper roll. The LED light is then activated for a predetermined time during which the DRAM is refreshed so as to retain the image. If the print copy button is depressed during this predetermined time interval, a further copy of the photo is output. After the predetermined time interval where no use of the camera has occurred, the onboard CPU shuts down all power to the camera system until such time as the take button is again activated, in this way, substantial power savings can be realised.

Jet Technologies The embodiments of the invention us an inkjet printer type device. Of course many different devices could be used However presently popular ink jet printing technologies are unlikely to be suitable.

The most significant problem with thermal inkjet is power consumption. This is approximately 100 times that required for high speed, and st ms from the energy-inefficient means of drop ejection. This involves the rapid boiling of water -19to produce a vapor bubble which expels the ink. Water has a very high heat capacity, and must be superheated in thermal inkjet applications. This leads to an efficiency of around 0.02%, from electricity input to drop momentum (and increased surface area) out.

The most significant problem with piezoelectric inkjet is size and cost. Piezoelectric crystals have a very small deflection at reasonable drive voltages, and therefore require a large area for each noszze. Also, each piezolectric actuator must be connected to its drive circuit on a separate substrate. This is not a significant problem at the current limit of around 300 nozzles per print head, but is a major impediment to the fabrication of pagewide print heads with 19,200 nozzles.

Ideally, the inkjet technologies used meet the stringent requirements of in-camera digital color printing and other high quaity, high speed, low cost printing applications. To meet the requirements of digital photography, new inkjet technologies have been created. The target features include: low power (less than 10 Watts) high resolution capability (1,6X) dpi or more) photographic quality output low manufacturing cost small size (pagewidth times minimum cross section) high speed 2 seconds per page) ART-END All of these features can be met or exceeded by the inkjet systems described below with differing levels of difficulty.

different inkjet technologies have been developed by the Assignee to give a wide range of choices for high volume manufacture. These technologies form part of separate applications assigned to the present Assignee as set out in the table below.

The inkjet designs shown here are suitable for a wide range of digital printing systems, from battery powered onerime use digital cameras, through to desktop and network printers, and through to comiercial printing systems For ease of manuficmee using standard process equipment, the print head is designed to be a monolithic 0.5 micron CMOS chip with MEMS post processing. For color photographic applications, the print head is 100 mm long, with a width which depends upon the inkjet type. The smallest prit head designed is U38, which is 0.35 mm wide, giving a chip area of square mm. The print heads each contain 19,200 nozzles plus data and control circuitry.

Ink is supplied to the back of the print head by injection molded plastic ink channels. The molding requires 50 micron features, which can be created using a lithographically micmrmachined insert in a standard injection molding tool. Ink flows through holes etched through the wafer to the nozzle chambers fabricated on the fi-ont surface of the wafer. The print head is connected t tthe camera circuitry by tape automated bonding.

Cross-Referenced Applications The following table is a guide to cross-referenced patent applications filed concurrently herewith and discussed hereinafter with the reference being utilized in subsequent tables when referring to a particular case: Docket No. Reference Title JO1 US i01 Radiant Plunger Ink Jet Printer U02US J102 Electrostatic Ink Jet Printer 1J03US IJ03 Planar Thenmolastic Bend Actuator Ink Jet J104US IJ04 Stacked Electrostatic Ink Jet Printer IJOSUS J05 Reverse Spring Lever Iak Jet Printer U06US J06 Paddle Type Ink Jet Printer U07US IJ07 Permanent Magnet Electromagnetic lnk Jet Printer IJ08US I08 Planar Swing Grill Electromagnetic Ink Jet Printer 0JO9US 1109 Pump Action Refill Ink Jet Printer 1U1OUS 110 Pulsed Magnetic Field Ink Jet Printer U13lUS Ill1 Two Plate Reverse Firing Electromagnetic Ink Jet Printer Ul2US 1112 Linear Stepper Actuator Ink Jet Printer 1113US 1113 Gear Driven Shutter Ink Jet Printer U114US I 14 Tapered Magnetic Pole Electromagnetic Ink Jet Printer 1115 Linear Spring Electromagnetic Grill Ink Jet Printer IJ 16US 1l16 Lorenz Diaphragm Electromagnetic Ink Jet Printer 11 TUIS 111 FiFE Surface Shooting Shuttered Oscillating Pressure Ink Jet Printer 1118US 1118 Buckle Grip Oscillating Pressu Ink Jet Printer 119US 1119 Shutter Based Ink Jet Printer IJ20 Curling Calyx Thermoelastic Ink Jet Printer IJ21 US 1121 Thermal Actuated nk Jet Printer IJ22US 1122 Iris Motion Ink Jet Printer 123US 123 Direct Firing Thennal Bend Actuator Ink Jet Printer LI24US 1124 Conductive PTFE Ben Activator Vented Ink Jet Printer [125 Magnetostrictive Ink Jet Printer J26US U26 Shape Memory Alloy Ink Jet Printer IJ27US 1327 Buckle Plate Ink Jet Printer IJ28US 1328 Thermal Elastic Rotary Impeller Ink Jet Printer IJ129US 129 Thenmoelastic Bend Actuator Ink let Printer )31US 1130 Thermoelastic Bend Actuator Using PTFE and Corrugated Copper Ink Jet Printer IJ31US I31 Bend Actuator Diret Ink Supply Ink Jet Printer U32US IJ32 A High Young's Modulus Thermolastic ink Jet Printer 1J33US 1U33 Thermally actuated slotted chamber wall inkjet printer IJ34US 134 Ink Jet Printer having a thenrmal actuator comprising an external coiled spring IJ35 Trough Container Ink Jet Printer U36US 1136 Dual Chamber Single Vertical Actuator Ink Jet U37US U37 Dual Nozzle Single Horizonta Fukinrum Actuator Ink Jet 1J38US U38 Dual Nozzle Single Horizontal Actuator ink Jet 139US IJ39 A single bend actuator cupped paddle inkjet printing devime 140F A thermally actuated ink jet printer having a series of thermal actuator units IJ41US U -41 A thermally actuated inkjet printer including a tapered heater element IJ42US IJ42 Radial Back-Curling Thermoelastic Ink Jet IJ43US IJ43 Inverted Radial Back-Curling Thermnoelastic Ink Jet IJ44US 1144 Surface bend actuator vented ink supply inkjet printer 14S Coil Actuated Mlagnetic Plate Ink Jet Printer Ink Jet Printing A large nunmber of new forms of ink jet printers have been developed to facilitate alternative inkjet technologies for the image processing and data distribution system. Various combinations of ink jet devices can be included in printer devices -21 incorporated as pa of the present invention. Australian Provisional Patent Applications relating to these ink jets which are specifically incorporated by cross reference include: Australian Filing Date Title Provisional Number P08066 15-Jul-97 Image Creation Method and Apparatus (IJ0 1)-WO99/03680 P08072 15-Jul-97 Image Creation Method and Apparatus (IJ02) -W099/03680 P08040 15-Jul-97 Image Creation Method and Apparatus (1103) -W99/03681 P8071 15-Jul-97 Image Creation Method and Apparatus (104) -WO99/03680 P08047 15-Jul-97 Image Creation Method and Apparatus (105) -WO99/03680 P08035 15-Jul-97 Image Creation Method and Apparatus (1506) -WO99103680 P08044 15-Jul-97 Image Creation Method and Apparatus (I107) -WO99/03680 PO8063 15-Jul-97 Image Creation Method and Apparatus (1108) -WO99/03680 P08057 15-Jul-97 Image Creation Method and Apparatus (U09) -WO99/0368 I P08056 15-Jul-97 Image Creation Method and Apparatus (IJ10) -WO99/0368 1 PO806 15-Jul-97 Image Creation Method and Apparatus (I311) -W099/03680 P08049 15-Jul-97 mage Creation Method and Apparatus (J12) -WO99/03680 P08036 15-Jul-97 Image Creation Method and Apparatus (113) -W099/03680 P08048 IS-Jul-97 Image Creation Method and Apparatus (IJ14) -WO99/03680 P08070 15-Jul-97 Image Creation Method and Apparatus (1J15) -WO99/03680 P08067 15-Jul-97 Image Creation Method and Apparatus (1116) -WO99/03680 P08001 15-Jul-97 Image Creation Method and Apparatus (Ul7) -WO99/0368I P08038 15-Jul-97 Image Creation Method and Apparatus (1118) -WO99/03681 P08033 15-Jul-97 Image Creation Method and Apparatus (1119)-US 6,254,220 P08002 15-Jul-97 Image Creation Method and Apparatus (1120) -WO99103681 P08068 1S-Jul-97 Image Creation Method and Apparatus (1321) -WO9910368 1 P08062 15-Jul-97 Image Creation Method and Apparatus (1322) -WO9903681 P08034 15-Jul-97 Image Creation Method and Apparatus (1)23) -WO99/03681 P08039 15-Jul-97 Image Creation Method and Apparatus (1124) -WO9910368 1 P08041 15-Jul-97 Image Creation Method and Apparso (025) -W099/03680 P08004 15-Jul-97 Image Creation Method and Apparatus (126) -W09903680 P08037 15-Jul-97 Image Creation Method and Apparatus (1127) -W099/036 81 P08043 15-Jul-97 Image Creation Method and Apparatus (128) -WO99/0368 I P08042 15-Jui-97 Image Creation Method and Apparatus (1129) -WO99/03681 P08064 15-Jul-97 Image Creation Method and Apparatus (1130) -WO99/03681 P09389 23-Sep-97 Image Creation Method and Apparatus (1131) -W099/03681 P09391 23-Sep-97 inage Creation Method and Apparatus (132)-US6,234,609 PP0888 12-Dec-97 Image Creation Method and Apparatus (1133) -WO99/0368 I PP0891 12-.Dec-97 Image Creation Method and Apparatus (134) -WO99/0368 I 12-Dec-97 Image Creation Method and Apparatus (IJ35) -WO99/03681 PPO873 12-Dec-97 Image Creation Method and Apparatus (i36) -WO99/0368 I PP0993 12-Dec-97 Image Creation Method and Apparatus (IJ37)-US 6,247,791 22 PP0890 12-Dec-97 Image Creation Method and Apparatus (IJ38) -US 6,336,710 PP 1398 19-Jan-98 An Image Creation Method and dApparatus (1339) -WO99103681 PP2592 25-Mar-98 An Image Creation Method and Apparatus (U140) -WO99/03681 PP2593 25-Mar-98 Image Creation Method and Apparatus (IJ41) WO99/03681 PP3991 9-Jun-98 Image Creation Method and Apparatus (142)-US 6,283,581 PP3987 9-Ju9-98 Image Creation Method and Apparatum (IJ43) -WO99/03681 PP3985 9-Jun-98 Image Creation Method and Apparatus (144) -WO99/03681 PP3983 9-Jun-98 Image Creation Method and Apparatus (1J45) -WO99/03681 I InkJet Manufacturing Further, the present application may utilize advanced semiconductor fabrication techniques in the construction of S large arrays of inkjet prinria. Suitable manufacturing techniques are described in the following Australian provisional patent specifications incorporated here by cross-reference: Australian Filing Date Title Provisional Number P07935 15-Jul-97 A Method of Manufacture of an Image Creation Apparatus (IJMOI) -WO99/03680 P07936 15-Jul-97 A Method of Manufacture of an Image Creation Apparatus (IJM02) -WO99/03680 P07937 15-Jul-97 A Method of Manufacture of an Image Creation Apparatus (IDM03) W099/03681 P08061 15-Jul-97 A Method of Manufacture of an Image Creation Apparatus (D1M04) -WO99/03680 P08054 15-Jul-97 A Method of Manufacture of an Image Creation Apparatus (IM05) -WO99/03680 P08065 15-Jul-97 A Method of Manufacture of an Image Creation Apparatus (IJM06) WO99/03680 P08055 15-Jul-97 A Method of Manufacture of an Image Creation Apparatus (IJMO7) -W099/03680 PO-053 15-Jul-97 A Method of Manufacture of an Image Creation Appartus (IJMOS) WO99/03680 P08078 15-Jul-97 A Method of Manufacture of an Image Creation Apparatus (IJM09) -WO99/03681 P07933 15-Jul-97 A Method of Manufacture of an Image Creation Apparatus (IJM 1O) -WO99/03681 P07950 15-Jul-97 A Method of Manufacture of an Image Creation Apparatus (M I1) WO9903680 P07949 15-Jul-97 A Method of Manufacture of an Image Creation Appai-tws (UM 12) -WO99/03680 P08060 15-Jul-97 A Method of Manufacture of an Image Creation Apparatus (UM 13) WO99/03680 P08059 15-Jul-97 A Method of Manufacture of an Image Creation Apparatus (tJM 14) -W099/03680) P08073 15-Jul-97 A Method of Manufacture of an Image Creation Apparatus (IM 15) -WO99/03680 P08076 15-Jul-97 A Method of Manufacture of an Image Creation Apparatus (UM 16) -WO9903680 P08075 15-Jul-97 A Method of Manufacture of an Image Creation Apparatus (UM 17) W 099/03681 PO8079 15-Jul-97 A Method of Manufacture of an Image Creation Apparatus (IM 18) -W099/0368 I P08050 15-Jul-97 A Method of Manufacture of an Image Creation Apparatus (iM 19) -WO99/03681 P08052 15-Jul-97 A Method of Manufacture of an Image Creation Apparatus (IJM20) -WO99/03681 P07948 15-Jul-97 A Method of Manufacture of an Image Creation Apparatus (IJM2 1) -WO99/03681 P07951 15-Jul-97 A Method of Manufacture of an Image Creation Apparatus (1JM22) -W099/03681 P08074 15-Jul-97 A Method of Manufacture of an Image Creation Apparatus (1JM23) -W099103681 P07941 15-Jul-97 A Method of Manufacture of an Image Creation Apparatus (tJM24) -WO99/03681 P08077 15-Jul-97 A Method of Manufacture of an Image Creation Apparatus (IJM25) -WO99/03680 PO8058 15-Jul-97 A Method of Manufacture of an Image Creation Apparatus (1JM26) -WO99/03680 P08051 15-Jul-97 A Merthod of Manufacture of an Image Creation Apparatus (IJM27) -WO99/03681 P08045 15-Jul-97 A Method of Manufacture of an Image Creation Apparatus (IJM28) -WO99036 81 P07952 15-Jul-97 A Method of Manufacture of an Image Creation Apparatus (IJM29) -WO9903681 P08046 15-Jul-97 A Method of Manufacture of an Image Creation Apparatus (IJM30) -WO99/03681 P08503 11-Aug-97 A Method of Manufacture of an Image Creation Apparatus (UM30a) -WO99/03681 P09390 23-Sep-97 A Method of Manufacture of an Image Creation Apparatus (DM31) -WO9903681 P09392 23-Sep-97 A Method of Manufiacure of an Image Creation Apparatus (IdM32) -WO99/03681 PP0889 12-Dec-97 A Method of Manufacture of an Image Creation Apparatus (DM35) -WO99/03681 PP0887 12-Dec-97 A Method of Manufacture of an Image Creation Apparatus (1JM36)-USSN 09/122,801 P0882 12-Dec-97 A Method of Manufacture of an Image Creation Apparatus (IJM37) -WO99/03681 PP0874 12-Dec-97 A Method of Manufacture of an Image Creation Apparatus (IJM38) -WO99/03681 PP1396 19-Jan-98 A Method of Manufacture of an Image Creation Apparatus (NM-39) -WO99/03681 PP2591 25-Mar-98 A Method of Manufacture of an Image Creation Apparatus (JM4 1) -WO99/03681 PP3989 9-Jun-98 A Method of Manufacture of an Image Creation Apparatus (JM40) -WO99/03681 PP3990 9-Jun-98 A Method of Manufacture of an Image Creation Apparatus (1JM42) -WO99/0368 1 PP3986 9-Jun-98 A Method of Manufacture of an Image Creation Apparatus (JIM43) -WO99/03681 PP3984 9-Jun-98 A Method of Manufacture of an Image Creation Apparatus (IM44) -WO99/03681 PP3982 9f-Jun-98 A Method of Manufacture of an Image Creation Apparatus (IJM45) -WO99/03680 Fluid Supply Further, the present application may utilize an ink delivery system to the ink jet head Delivery systems relating to the S supply of ink to a series of ink jet nozzles are described in the following Australian provisional patent specifications, the disclosure of which are hereby incorporated by cross-refence: Australian Filing Date Title Provisional Number P08003 15-Jul-97 Supply Method and Apparatus (F1) -WO99/03681 P8005 15-Jul-97 Supply Method and Apparatus -WO99/04368 P09404 23-Sep-97 A Device and Method (F3)-USSN 09/113,101 MEMS Technology Further, the present application may utilize advanced semiconductor microclectromnchanical techniques in the construction of large armays of ink jet printers. Suitable microelectromechanical techniques are described in the following Australian provisional patent specifications incorporated here by cross-referenc Australian Filing Date Title Provisional Number P07943 15-Jul-97 A device (MEMSOI) -W 99/03681 PO8006 15-Jul-97 A device (MEMSO2) -WO99/03681 24- P08007 15-Jul-97 A device (IMEMSO3) -W099/03681 P0800)8 15-Jul-97 A device (NIEMSO43 -W099031681 P0801 0 15-4u-97 A device (MEMSO5) -W0991L681 P08011 15-Jul-97 A device (MEMS06) -W099/0368 I P07947 15-Jul-97 A device (MEMSO7) -W099,'0368 I P07945 1 5-Jul-97 A device (MEMISOS) -W0?.9/0368 1 P07944 151-7A device (M EM 809) -W099/10368 I P07946 1 5-Jul-97 A device (MEMS 10) -W099,/0368 I P09393 2 3-Sem-97 A Device and Method (MEMS 11) -W099/0368 I PP0875 12-Dec.-97 A Device (MEMS 12) -W099/0368I PP0894 l 2-Dec-97 A Device and Method (M EMS 13) -W099/03 681I JR Technologies Further, the present application may include the utilization of a disposable camer system such as those described in dte following.Australian provisionali patent specifications incorporated here bycosrfrne Australian Filing Date Title Provisional PP0895 12-Dec-97 An Image Creation Method and Apparatus (IROl1) -W099/0455 1 220870 12-Dec-97 A Device and Methd (11(02) W099/04551 PP0869 12-Dec-97 A Deviceand Method (11(04) W099/04551 220887 12-Dec-97 Image Creation Method and Apparatus (11(05) W099,104551I P20885 *2-Dec-97 An Image Production System (11(06) W099/0455 I PP0884 12-Dec-97 image Creation Method and Apparatus (IRIO0) W09910455 I PP0886 12-Dec-97 Imiage Crea.tion Method and Apparatus (11412) W099/04551 PP0871 12-Dec-97 A Device and Method (11(13) W099!04551I PF0876 12-lDec-97 An Image Processing Methiod and Apparatus (1K 14) W099i0455 I 220878 127-Dec -97 A Device and Method (T1(1) W099104551 2P0879 12-Dec-97 A Device and Method (IRIS) W099/04551 PP088(3 12-Dec-97 jA Device and Method (11(19) W099!0455 I P20880 12-Dec-97 JA Device and Method (11(20) W099/04551 220881 12-Dec-97 [A Device and Method (11(21) W099V/04551 DotCard Technologies o Further, the present application may include the utlization of a data distribution system such as Chat described in the following Australian pro-visional patent specifications incorporated here by cosrfrne Austalian Filing Datte Title Provisional NumberI 2R30-AU PP2370 I16-Mar-98 jData Processing Method and Apparatus (Dot0l)-USSN 09/112,781 PP2371 i6-Mar-98 Data Processing Method and Apparatus (Dot02-iUSSN 09/113,052

I

Artcamn Technologies Further, the present application may include the utilization of camera and data processing techniques such as an ArIcam type device as described in the following Australian provisional patent specifications incorporated here by crossreference: Australian Filing Date Title Provisional Number P07991 15-Jul-97 Image Processing Method and Apparatus (ARTO1}-WO99/04368 P07988 15-Jul-97 Image Processing Method and Apparatus (ARTO2) -WO99/04368 P07993 15-Jul-97 Image Processing Method and Apparatus (ART03) -W099/04368 P08012 15-Jul-97 Image Processing Method and Apparatus (ARTO5) -WO99/04368 P08017 15-Jul-97 Image Processing Method and Apprau. (ARTO6) -W099/04368 P08014 15-Jul-97 Media Device (ARTO7) -W99/04368 P08025 15-Jul-97 Image Processing Method and Apparatus (ART08) -WO99/04368 P08032 15-Jul-97 Image Processing Method and Apparatus (ARTO9) -WO99/04368 P07999 15-Jul-97 Image Processing Method and Apparatus (ARTIO) -W099/t4368 PO7998 15-Jul-97 Image Processing Method and Apparatus (ARTI I1) -W099/04368 P08031 15-Jul-97 Image Processing Method and Apparatus (ART12) -WO99/04368 P08030 15-Jul-97 Media Device (ART13) -WO99/04368 P07997 15-Jul-97 Media Device (ARTIS) -WO99/04368 P07979 15-Jul-97 Media Device (ARTI6) -WO99/04368 P08015 15-Jul-97 Media Device (ARTI7) -WO99/04368 P07978 15-Jul-97 Media Device (ARTIS) -UJSSN 09/113,067 P07982 15-Jul-97 Data Processing Method and Apparatus (ARTI9) -WO99/04368 P07989 15-Jul-97 Data Processing Method and Apparatus (ART20) -WO99/04368 19 15-Jul-97 Media Processing Method and Apparatus (ART2 1) -WO99/04368 P07980 15-Jul-97 Image Processing Method and Apparatus (ART22) -W99/04368 P07942 15-Jul-97 Image Processing Method and Apparatus (ARl3) -W099/04368 PO8018 15-Jul-97 Image Processing Method and Apparatus (ART24) -WO99/i04368 P07938 15-Jul-97 Image Processing Method and Apparatus (ART25) -W09Y9/04368 P08016 15-Jul-97 Image Processing Method and Apparatus (ART26) -WO9904368 P8024 15-Jul-97 Image Processing Method and Apparatus (ART27) -WO9904368 P07940 15-Jul-97 Data Processing Method and Apparatus (ART28) -WO99/04368 P07939 15-Jul-97 Data Processing Method and Apparatus (ART29) -WO99/04368 PO8501 1 I -Aug-97 Image Processing Method and Apparatus (ART30)-1US 6,137,500 PO8500 11-Aug-97 Image Processing Method and Apparatus (ART31) L'SSNO9i 12,796 P07987 15-Jul-97 Data Processing Method and Apparatus (ART32) -WO99/04368 P08022 15-Jul-97 Image Processing Method and Apparatus (ART33) -W099/04368 26 P08497 11-Aug-97 Image Processing Method and Apparatus (ART30) -US 6,137,500 P08029 15-Jul-97 Sensor Creation Method and Apparatus (ART36) -WO99/04368 P07985 iS-Jul-97 Data Processing Method and Apparatus (ART37) -WO99/04368 P08020 15-Jul-97 Data Processing Method and Apparatus (ART38) -WO99/04368 P08023 15-Jul-97 Data Processing Method and Apparatus (ART39) -WO99/04368 P09395 123-Sep-97 Data Processing Metho ad Apparatus (ART4)-US 6,322,181 P08021 15-Jul-97 Data Processing Method and Apparatus (ART40) -WO99/04368 P08504 I1-Aug-97 Image Prcessing Method and Apparatus (ART42)-USSN 09/112,786 P8000 15-Jul-97 Data Processing Method and Apparatus (ART43) -WO99/04368 P07977 15-Jul-97 Data Processing Method and Apparatus (ART44}-USSN 09/112,782 P07934 15-Jul-97 Data Processing Method and Apparatus (ART45)-USSN 09/113,056 P07990 15-Jul-97 Data Processing Method and Apparatus (ART46) -USSN 09/113,059 P08499 I1-Aug-97 Image Processing Method and Apparatus (ART47) -USSN 09113,091 P08502 11-Aug-97 image Processing Method and Apparatus(ART48)-US 6,381,361 P07981 15-Jul-97 Data Processing Method and Apparatus (ART50)-US 6,317,192 PO7986 15-Jul-97 Data Processing Method and Apparatus(ARTS 1)-USSN 09/113,057 P07983 15-Jul-97 Data Procetssing Method and Apparatus (ART52) -USSN 09/113,054 P08026 15-Jul-97 Image Processing Method and Appamtus (ART53)-USSN 09/112,752 P08027 15-Jul-97 Image Processing Method and Apparatus (ART54-USSN 09/112,759 P08028 15-Jul-97 Image Processing Method and Apparatus (ART56)-USSN 09/112,757 PO9394 23-Sep-97 Image Processing Method and Apparatus (ART57) )-US 6,357,135 P09396 23-Sep-97 Data Processing Method and Apparatus (ART58)-USSN 09/113,107 P09397 23-Sep-97 Data Processing Method and Apparatus (ART59) -WO99/0368 1 P09398 23-Sep-97 Data Processing Method and Apparatus (ART6$-US 6,353,772 P9399 23-Sep-97 Data Processing Method and Apparatus (ART6 1)-US 6,106,147 P09400 23-Sep-97 Data Processing Method and Apparatus (ART62)-USSN 09/112,790 P09401 23-Sep-97 Data Processing Methiod and Apparatus (ART63)-US 6,304,291 PO9402 23-Sep-97 Data Processing Metiod ad Apparatus (ART64) -USSN 09/112,788 P09403 23-Sep-97 Data Proccsing Method and Apparatus (ART65)-tUS 6,305,770 P09405 23-Sep-97 Data Processing Method and Apparatus (ART66)-US 6,289,262 PP0959 16-Dec-97 A Data Processing Method and Apparatus (ART68) -US 6,315,200 PP1397 19-Jan-98 A Media Device (ART69)US 6,217,165 It would be appreciated by a person skilled in the art that numerous variations and'or modifications may be made to the present invention as shown in the specific embodiment wvithout departing from the spirit or scope of the invention as broadly described. The present embodiment is, therefore, to be considered in all respects to be illustrative and not restrictive.

-27 Tables of Drop-on-Demand Inkjets Eleven important characteristics of the fundamental operation of individual inkjet nozzles have been identified These characteristics are largely orthogonal, and so can be elucidated as an eleven dimensional matrix, Most of the eleven axes of this matrix include entries developed by the present assignee.

The following tables form the axes of an eleven dimensional table of inkjet types.

Actuator mechanism (18 types) Basic operation mode (7 types) Auxiliary mechanism (8 types) Actuator amplification or modification method (17 types) Actuator motion (19 types) Nozzle refill method (4 types) Method of restricting back-flow through inlet (10 types) Nozzle clearing method (9 types) Nozzle plate constructonn (9 types) Drop ejection direction (5 types) Ink type (7 types) The complete eleven dimensional table represented by these axes contains 36.9 billion possible configurations of inkjet nozzle. While not all of the possible combinations result in a viable inkjet technology, many million configurations are vable. It is clearly impractical to elucdate all of the possible configurations. Instead, certain inkjet types have been investigated in detail. These are designated 1J01 to IJ45 above.

Other inkjet configurations can readily be derived from these 45 examples by substituting alternative configurations along one or more of the 11 axes. Most of the 1301 to 1345 examples can be made into inkjet print heads with characteristics superior to any currently available inkjet technology, Where there are prior art examples known to the inventor, one or more of these examples ar listed in the examples column of the tables below. The 1101 to L45 series are also listed in the examples couinn. In some cases, a printer may be listed more than once in a table, where it shares characteristics with more than one entry Suitable applications include: Home printers, Office network printers, Short run digital printers, Commercial print systems, Fabric print Pprint, P rinters, Internet WWW printers, Video printers, Medical imaging, Wide format printers, Notebook PC printers, Fax machines, Industrial printing systems, Photocopiers, Photographic minirabs etc The information associated with the aforementioned i dimensional matrix are set out in the following tables.

Actuator mechanism (applied only to selected ink drops) __1111111 Actuator Mechanism Thermal bubble Description An electrothermal heater heats the ink to above boiling point, transferring significant heat to the aqueous ink. A bubble nucleates and quickly forms, expelling the ink.

The efficiency of the process is low, with typically less than 0.05% of the elecrical energy being transformed into kinetic energy of the drop.

Advantages Large force generated Simple construction No moving parts Fast operation Small chip area requiahd for actuator SDisadvantages Diavaae Piezoelectric Electro-strictive A piezoelectric crystal such as lead lanthanum zirconate (PZT) is electrically activated, and either expands, shears, or bends to apply pressure o the ink, ejecting drops.

Low power consumption Many ink types can be used Fast operation High efficiency

I

High power Iik carrier limited to water Low efficiency High temperatures required High mechaical stress Unusual materials required Large drive transistors Cavitation causes actuator failure Kogation reduces bubble formation Large print heads are difficult to fabricate Very large area required for actuator Difficult to integrate with electronics High voltage drive transistors required Full pagewidth print heads impractical due to actuator size Requires electrical poling in high field strengths during nanufacture Low maximum strain (approx. 0.01%) Large area tequired for actuator due to low strain Response speed is marginal 10 ps) High voltage drive transistors required Full pagewidth print heads impractical due to actuator size Examples Canon Bubbiejet 1979 Endo et al GB patent 2,007,162 Xerox heater-in-pit 1990 Hawkins et al USP 4,899,181 Hewlett-Packard TIJ 1982 Vaught et al USP 4,490,728 Kyser et at USP 3,946,398 Zoltan USP 3,683,212 1973 Stemme USP 3,747,120 Epson Stylus Tektronix IJ04 Seiko Epson, Usui et all JP 253401/96 IJ04 An electric field is used to activate electrostriction in relaxor rnaerials such as lead lanthanum zirconate titanate (PLZT) or lead magnesium niobate (PMN).

Low power consumption Many ink types can be used Low thermal expansion Electric field strength required (approx.

V/n) can be generated without difficulty Does not require electrical pling

I

i -II 11~ ~11~1111~11~ Ferroelectric Electrostatic plates An electric field is used to induce a phase transition between the antifeTroelecric (AFE) and ferroelectric (FE) phase. Perovskite materials such as tin modified lead lanthanum zirconate titanate (PIISnT) exhibit large strains of up to 1% associated with the AFE to FE phase transition.

Low power consumption Many ink types can be used Fast operation I is) Relatively high longitudinal strain High efficiency Electric field strength of around 3 V/tpm can be readily provided Low power consumption Many ink types can be used Fast operation Difficult to integrate with electronics Unusual materials such as PLZSnT are required Actuators require a large area Conductive plates are separated by a compressible or fluid dielectric (usually air).

Upon application of a voltage, the plates attract each other and displace ink, causing drop ejection. The conductive plates may be in a comb or honeycomb structure, or stacked to increase the surface area and therefore the force.

A strong electric field is applied to the ink, whereupon electrostatic attraction accelerates the ink towards the print medium.

Difficult to operate electrostatic devices in an aqueous environment The electrostatic actuator will normally need to be separated from the ink Very large area required to achieve high forces High voltage drive transistors may be required Full pagewidth print heads are not competitive due to actuator size 1302, 104 Electrostatic pull on ink Low current consumption Low temperature High voltage required May be damaged by sparks due to air breakdown Required field strength increases as the drop size decreases High voltage drive transistors required Eectrostatic field attracts dust 1989 Saito et al, USP 4,799,068 1989 Miura et a, USP 4,810,954 Tone-jet I f 1~__~111111_1---1111 ___111111 I I Permanent magnet electro-magnetic An electromagnet directly attracts a permanent magnet, displacing ink and causing drop ejection. Rare earth magnets with a field strength around 1 Tesla can be used. Exanples are: Samarium Cobalt (SaCo) and magnetic materials in the neodymium iron boron family (NdFeB, NdDyFeBNb, NdDyFcB, Cec) Low owwer consumption Many ink types can be used Fast operation High efficiency Easy extension from single nozzles to pagewidth print heads r Complex fabrication Permanent magnetic material such as Neodymium iron Boron (NdFeB) required.

High local currents required Copper metalization should be used for long electromrigration lifetime and low resistivity Pigmented inks are usually infeasible Operating temperature limited to the Curie temperature (around 540 K) 1,107, 111O 1111 Soft magnetic core electro-magnetic A solenoid induced a magnetic field in a soft magnetic core or yoke fabricated from a fnrouis material such as electroplated iron alloys such as CoNiFe CoFe, or NiFe alloys Typically, the soft magnetic material is in two parts, which are normally held apart by a spring. When the solenoid is actuated, the two parts attract, displacing the ink.

The Lorenz force acting on a curent carrying wire in a magnetic field is utilized.

This allows the magnetic field to be supplied externally to the print head, for example with rare earth permanent magnets.

Only the current carrying wire need be fabricated on the print-hed, simplifying materials requirements.

Low power consumption Many ink types can be used Fast operation High efficiency Easy extension from single nozzles to pagewidth print heads Complex fabrication Materials not usually present in a CMOS fab such as NiFe, CoNiFe, or CoFe are required High local currents required Copper imetalization should be used for long electromigration lifetime and low resistivity Electroplating is required High saturation flux density is required (2.0-2.1 T is achievable with CoNiFe Force acts as a twisting motion Typically, only a quarter of the solenoid length provides force in a useful direction High local currents required Copper metalization should be used for long electromigration liftime and low resistivity Pigmented inks are usually infeasible D01, IJ05, 1l08, IJO IJ12, 114, U 15, 117 IJ06, lJ 1, IJ 3,J 6 Magnetic Lorenz force Low power consumption Many ink types can be used Fast operation High efficiency Easy extension from single nozzles to pagewidth print heads i -~~~~~~1111~---~1111Illll~ ~YIIIIIII- Magneto-striction Surface tension reduction The actuator uses the giant magneostrictive effect of materials such as Terfenol-D (an alloy ofterbium, dysprosium and iron developed at the Naval Ordnance Laboratory, hence Ter-Fe- NOL). For best efficiency, the actuator should be pro-stressed to approx. 8 MPa.

Ink under positive pressure is held in a nozzle by surface tension. The surface tension of the ink is reduced below the bubble threshold, causing the ink to egress fromn the nozle.

The ink viscosity is Ically reduced to select which drops are to be ejeted. A viscosity reduction n a be achieved electrothermally with most inks, but special inks can be engineered for a 100:1 viscosity reduction.

An acoustic wave is generated and focussed upon the drop ejection region.

Many ink types can be used Fast operation Easy extension from single nozzles to pagewidth print heads High force is available Low power consumption Simple construction No unusual materials required in fabrication High efficiency Easy extension from single nozzles to pagewidth print heads Simple construction No unusual materials required in fabrication Easy extension from single nozzles to pagewidth print heads Force acts as a twisting motion Unusual materials such as Terfenol-D are required High local currents required Copper metaization should be used for long electromigration lifetime and low resistivity Pre-stressing may be required Requires supplementary force to effect drop separation Requires special ink surfactants Speed may be limited by surfactant properties Requires supplementary force to effect drop separation Requires special ink viscosity properties High speed is difficult to achieve Requires oscillating ink pressure A high temperature difference (typically 80 degrees) is required Fischenbeck, USP 4,032,929 1I25 Silvesbrook, EP 0771 658 A2 and related patent applications Viscosity reduction Silverbrook, EP 0771 658 A2 and related patent applications Acoustic Can operate without a nozzle plate Complex drive circuitry Complex fabrication Low efficiency Poor control of drop position Poor control of drop volume 1993 Hadimioglu et at, EUP 550,192 1993 Elrod et al, EUP 572220 1 111 11 32 Thermoelastic bend actuator High CTE thermoelastic actuator An actuator which relies upon differential thermal expansion upon Joule heating is used.

A material with a very high coefficient of thernal expansion (CTE) such as polytetrafluoroethylene (PTFE) is used. As high CTE materials are usually non-conductive, a heater fabricated from a conductive material is incorporated. A 50 pm long PTFE bend actuator with polysilicon heater and 15 rnW power input can provide 180 iN force and 10 l.m deflection. Actuator motions include: Bend Push Buckle Rotate Low power consumption Many ink types can be used Simple planar fabrication Small chip area required for each actuator Fast operation High efficiency CMOS compatible voltages and currents Standard MEMS processes can be used Easy extension from single nozzles to pagewidth print heads High force can be generated PTFE is a candidate for low dielectric constant insulation in ULSI Very low power consumption Many ink types can be used Simple planar fabrication Small chip area required for each actuator Fast operation High efficiency CMOS compatible voltages and currents Easy extension from single nozzles to pagewidth print heads Efficient aqueous operation requires a thermal insulator on the het side Corrosion prevention can be difficult Pigmented inks may be infeasible, as pigment particles may jam the bend actuator 1103, 1109, 1317, 1118 U19, IJ20, U21, 1122 U23, 1124, 27, U28 U29, [130, IJ31, 132 1J33, 134, 1335, 1136 IJ37, 1138 ,I39, 1140 1U41 Requires special material PTFE) Requires a PTFE deposition prcess, which is not yet standard in ULSI fabs PTFE deposition cannot be followed with high tempeature (above 350 processing Pigmented inks may be infeasible, as pigment paricles may jam the bend actuator 109, 1117, i 18, 121, IJ22, 123, IJ24 U27, U28, 1129, 1330 1J31, 1142, I43, IJ44 I.r 111 1 Conductive polymer thermoelastic actuator A polymer with a high coefficient of thermal expansion (sudc as PTFE) is doped with conducting substances to increase its conductivity to about 3 orders of magnitude below that of acpper. The conducting polymer expands when resistively heated.

Examples of conducting dopants include: Carbon nanotubes Metal fibers Conductive polymers such as doped polythiophene Carbon granules A shape memory alloy such as TiNi (aiso known as Nitinol Nickel Titanium alloy developed at the Naval Ordnance Laboratory) is thermally switched between its weak martensitic state and its high stiftiess austenic state. The shape of the actuator in its martensitic state is deformed relativc to the austenic shape. The shape change causes ejection of a drop.

High force can be generated Very low power consumption Many ink types can be used Simple planar fabrication Small chip area required for each actuator Fast operation High efficiency CMOS compatible voltages and currents Easy extension from single nozzles to pagewidth print heads Shape memory alloy High force is available (stresses of hundreds of MPa) Large strain is available (more than 3%) High corrosion resistance Simple construction Easy extension from single nozzles to pagewidth print heads Low voltage operation Linear Magnetic actuators can be constructed with high thrust, long ravel, and high efficiency using planar seniconductor fabrication techniques Long actuator travel is available Medium force is available Low voltage operation Requires special materials development (High CTE conductive polymer) Requires a PTFE deposition process, which is not yet standard in ULSI fabs PTFE deposition cannot be followed with high temperature (above 350 0 C) processing Evaporation and CVD deposition techniques cannot be used Pigmented inks may be infeasible, as pigment particles may jam the bend actuator Fatigue limits maximum number of cycles Low strain is required to extend fatigue resistance Cycle rate limited by heat removal Requires unusual materials (TiNi) 'The latent heat oftransformation must be provided High current operation Requires pre-stressing to distort the martensitic state Requires unusual semiconductor materials such as soft magnetic alloys CoNiFe Some varieties also require permanent magnetic materials such as Neodymium iron boron (NdFeB) Requires complex multi-phase drive circuitry High current operation Linear Magnetic Actuator Basic operation mode Linear magnetic actuators include the Linear Induction Actuator (LIA), Linear Penmanent Magnet Synchronous Actuator (LPMSA), Linear Reluctance Synchronous Actuator (LRSA), Linear Switched Reluctance Actuator (LSRA), and the Linear Stepper Actuator

(LSA).

i I tXmul.'. cx-_ I uspoanuaaiJ mnioue Actuator directly pushes ink This is the simplest mode of operation: the actuator directly supplies sufficient kinetic energy to expel the drop. The drop must have a sufficient velocity to overcome the surface tension.

Advantages Simple operation No external fields required Satellite drops can be avoided ifdrop velkcity is less than 4 mrs Can be efficient, depending upon the actuator used Disadvantages Drop repettion rate is usually limited to less than 10 KHz. However, this is not fundamental to the method, but is related to the refill method normally used All of the drop kinetic energy must be provided by the actuator Satellite drops usually form if drop velocity is greater than 4.5 m/s Examples Thermal inkjet Piezoelectric inkjet 1301, 102, IJ03,104 J05, 1306, 3U07, 1109 l111, IU12,1314, 116 1J20, IJ22, UJ23, 1124 IJ25, IJ26, 1U27, 128 1329, IJ30, IU31, I32 1333, 1134, 1135, 1J36 1137, 1J38, 1339, J140 1141, 1U42, U43, 1I44 Proximity Elctrostatic pull ona ink Magnetic pull on ink The drops to be printed are selected by some Very s manner thermally induced surface tension be use reduction of pressurized ink), Selected drops The dn are separated from the ink in the nozzle by need t contact with the print medium or a transfer separa roller, 'Hne drops to be printed are selected by some Very si manner thromally induced surface tension be use reduction of pressuried ink). Selected drops The dn are separated from the ink in the nozzle by a need to strong electric field. separat I i imple print head fabrication can op selection means does not provide the energy required to te the drop from the nozzle imple print head fabrication can op selection means does not Sprovide the energy required to Ste drop from the nozzle Requires close proximity between the print head and the print media or transfer roller May require two print heads printing alternate rows of the image Monolithic color print heads are difficult Requires very high electrostatic field Electrostatic field for small nozzle sizes is above air breakdown Electrostatic field may attract dust Requires magnetic ink Ink colors other tfan black are difficult Requires very high magnetic fields Silverbrook, EP 0771 658 A2 and related patent applications Silverbrook, EP 0771 658 A2 and related patent applications Torne-Jet Silverbrook, EP 0771 658 A2 and related patent applications The drops to be printed are selected by some manner thernally induced surface tension reduction ofpressurized ink). Selected drops are separated from the ink in the nozzle by a strong magnetic field acting on the magnetic ink Very simple print head fabrication can be used The drop selection means does not need to provide the energy required to separate the drop from the nozzle R3- .4 1R30-AUr Shutter Shuttered grili The actuator moves a shutter to block ink flow to the nozzle The ink pressure is pulsed at a multiple of the drop ejection frequency.

The actuator moves a shutter to block ink flow through a grill to the nozzle. The shutter movement need only be equal to the width of the grill holes.

A pulsed magnetic field attrats an 'ink pusher' at the drop ejection frequency. An actuator controls a catch, which prevents the ink pusher from moving when a drop is not to be ejected.

High speed (>50 KHz) operation can be achieved due to reduced refill time Drop timing can be very accurate The actuator energy can be very low Actuators with small travel can be used Actuators with small force can be used High speed (>50 KCHz) operation can be achieved Extremely low energy operation is possible No heat dissipation problems Moving parts are reuired Requires ink pressure modulator Friction and wear must be considered Stiction is possible T 113, 5 7, 62-1 i Moving pans are required Requires ink pressure modulator Friction and wear must be considered Stiction is possible Requires an external pulsed magnetic field Requires special materials for both the actuator and the ink pusher Complex construction IJ08, 5lS, J118, I19 Pulsed magnetic pull on ink pusher

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Auxiliary mechanism (applied to all nozzles) i Auxiliary mechanism (applied to all nozzles) Auxiliary Mechanism None Oscillating ink pressure (including acoustic stimulation) Description Advantages Disadvantages The actuator directly fires the ink drop, and there is no external field or other mechanism requiyed.

The ink pressure oscillates, providing much of the drop ejection energy. The actuator selects which drops are to be fired by selectively blocking or enabling nozzles. The ink pressure oscillation may be achieved by vibrating the print head, or preferably by an actuator in the ink supply.

Simplicity of constrction Simplicity of operation Small physical size Drop ejection energy must be supplied by individual nozzle actuator Examples Most inkjets, including piezoelectric and thermal bubble.

IJO1- U07, 1109, 1 11 J112, 1114, 120, IJ22 1123-145 Silverbrook, EP 0771 658 A2 and related patent applications 1J08, I313, 1J15, 117 Jl18, I19, 1121 Oscillating ink pressure can provid refill pulse, allowing higher operat speed The actuators may operate with m lower energy Acoustic lenses can be used to foe the sound on the nozzes e a Requires external ink pressure oscillator ing Ink pressure phase and amplitude must be carefully controied uch Acoustic reflections in the ink chamber must be designed for us 1 1 n unn N Media proximity Transfer roller Electrostatic Direct magnetic fiedd The print head is placed in close proxinity to the print medium. Selected drops protrude from the print head irther than unselected drops, and contact hie print medium. The drop soaks into the medium fast enough to cause drop separation.

Drops arc printed to a transfer iroler instead of straight to the print medium. A transfer roller can also be used for proximity drop separation.

An electric field is used to accelerate selected drops towards the print medium.

Low power High accuracy Simple print head construction Precision assembly required Paper fibes may cause problems Cannot print on rough substrates High accuracy Bulky Ik Wide range of print substrates can be used Ink can be dried on the transfer roller Low power Simple print head construction Low power Simple print head construction Expensive Complex construction Field strength required for separation of small drops is near or above air breakdown Silverbrook, EP 0771 658 A2 and related patent applications Silverbrook, EP 0771 658 A2 and related patent applications Tektronix hot melt piezoelectric inkjet Any of the iJ series Silvabrook, EP 0771 658 A2 and related patent applications Tone-Jet Silverbrook, EP 0771658 A2 and related patent applications A magnetic field is used to accelerate selected drops of magnetic ink towards the print medium.

Cross magnetic field Pulsed magnetic field The print head is placed in a constawn magnetic fieldi The Lorenz force in a current carrying wire is used to move the actuator.

A pulsed magnetic field is used to cyclically attract a paddle, which pushes on the ink. A small actuator moves a catch, which selectively prevents the paddle from moving.

Does not require magnetic materials to be integrated in the print head manufacturing process Requires magnetic ink Requires strong magnetic field Requires external magnet Current densities may be high, resulting in electromigration problems Complex print head construction Magnetic materials required in print head It06, U16 1310 Very low power operation is possible Small print head size Actuator amplification or modification method Actuator amplification Description Advantages Disadvanages Examples None No actuator mechanical amplification is used Operational simplicity Many actuator mechanisms have insufficient trawve, fIhenal Bubble Inkjet The actuator directly drives the drop ejection or insufficient force, to efficiently drive the drop 10J1, 1302, U06, U07 process. i ejection process 1 16, 125, 1126 il'~ Differenatial expansion bend actuator Transient bend actuator i -i An actuator material expands more on one side than on the other. The expansion may be thenral, piezoelectric, magnetostrictive, or other mechanism.

A trilayer bend.actuator where e e two outside layers are identical This cancels bend due to ambient temperature and residual stress. The actuator only responds to transient heating of one side or the other.

A series of thin actuators are stacked. This can be apprpiate where actuators require high electric field strength, such as eectrostatic and piezoelectric actuators.

Actuator stack Multiple actuators Linear Spring Reverse spring Provides greater travel in a reduced print head area The bend actuator converts high force low travel actuator mechanism to high travel, lower force mechanism.

Very good temperature stability High speed, as a new drop can be fired before heat dissipates Cancels residual stress of formation Increased travel Reduced drive voltage Increases the force available from an actuator Multiple actuators can be positioned to control ink flow accurately Matches low ravel actuator with higher travel requirements Non-contact method of motion transformation Better coupling to the ink High stresses are involved Care must be taken that the materials do not delaminate Residual bend resulting from high temperature or high stress during formation High stesses are involved Care must be taken that the materials do not delaminate 1103, 109, I117-IJ24 1127, 1129-J39, J142, 1343, U44 -J40, 4 Increased fabrication complexity Increased possibility of short circuits due to pinholes Some piezoelectric ink jets IJ04 Multiple smaller actuators are used Ssimultaneously to move the ink. Each actuator need provide only a portion of the force required.

A linear spring is used to ransform a motion with small tavel and high force into a longer travel, lower force motion.

The actuator loads a spring. When the actuator is tumed of, the spring releases. This can reverse the force/distance curve of the actuator to make it compatible with the force'time requirements of the drop ejection.

Actuator forces may not add linearly, reduc efficiency Requires print head area for the spring Fabrication complexity High stress in the spring ing 1312, 1113, 3J18, 120 IJ22, 1J28, 1342, IJ43 -1 IJo5, 1i 1 Coiled actuator Flexure bend actuator Gears Catch i A bend actuator is coiled to provide greater travel in a reduced chip area A bend actator has a small region near ihe fixture point, which flexes much more readily than the rmnainder of the actuator. The actuator flexing is effectively converted from an even coiling to an angular bend, resulting in greater travel of the actuator tip.

Gears can be used to increase travel at the expense of duration. Circular gears, rack and pinion, ratchets, and other gearing methods can be used.

The actuator controls a small catch. The catch either enables or disables movement of an ink pusher that is controlled in a bulk manner.

Incrases travel Reduces chip area Planar implementations are relatively easy to fabricate.

Generally restricted to planar implementations due to extreme fabrication difficulty in othe orientations.

1117, 1U21, U34, 1J35 I Simple means of increasing travel of a bend actuator Care must be taken not to exceed the elastic limit in the flexure area Stress distribution is very uneven Difficult to accurately model with finite element analysis J11, 1119, 1J33 Low force, low travel actuators can be used Can be fabricated using standard surface MEMS processes Very low actuator energy Very small actuator size i I Moving parts are required Several actuator cycles are required More complex drive electronics Complex construction Friction, friction, and wear are possible Complex construction Requires external force Unsuitable for pigmented inks Buckle plate A buckle plate can be used to change a slow actuator into a fast motion. t can also convert a high force, low travel actuator into a high travel, medium force motion.

A tapered magnetic pole can increase travel at the expense of force.

SVery fast movement achievable Must stay within elastic limits of the materials for long device life High stresses involved Generally high power requirement S Hirata et al, "An Ink-jet Head Proc. IEEE MEMS, Feb. 1996, pp418-423.

U118, IJ27 Ti14 i i Tapered magnetic pole i

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Linearizes the magnetic force/distance curve Complex construction A lever and fulcrum is used to transform a motion with small travel and high force into a motion with longer travel and lower force. The lever can also reverse the direction of travel.

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Matches low travel actuator with higher travel requirements Fulcuram area has no linear movement, and can be used for a fluid seal -r High stress around the futcmrum 1132, 136, 1J37 !I 1~~1111111--- I 1 Rotary impeller The actuator is connected to a rotary impeller.

A small angular deflection of the actuator results in a rotation of the impeller vanes, which push the ink against stationary vanes and out of the nozzle High mechanical advantage The ratio of force to travel of the actuator can be matched to the nozzle requirements by varying the number of impeller vanes No moving parns Complex construction Unsuitable for pigmented inks Large area required Only relevant for acoustic ink jets Acoustic lens A refractive or diffactive zone plate) acoustic lens is used to concentrate sound waves.

A sharp point is used to concentrate an electrostatic field.

1993 Hadimiogii et al, EUP 550,192 1993 Elrod et ai, EUP 572,220 Tone-jet Sharp conductive point Simple construction Difficult to fabricate using standard VLSI processes for a surface ejecting ink-jet Only relevant for electrostatic ink jets Actuator motion Actuator motion Volume expansion Linear, normal to chip surface Linear, parallel to chip surface Membrane push Lsescnpnton The volume of the actuator changes, pushing the ink in all directions, The actuator moves in a direction normal to the print head surface. The nozzle is typically in the line of movement.

The actuator moves parallel to the print head surface. Drop ejection may still be nonmai to the surface.

An actuator with a high force but small area is used to push a stiff membrane that is in contact with the ink.

Advantages Simple construction in the case of thermal ink jet Efficient coupling to ink drops ejected normal to the surface Disadvantages High energy is typically required to achieve volume expansion. This leads to thermal stress, cavitation, and kogation in thermal inkjet implementations High fabrication complexity may be required to achieve perpendicular motion Fabrication complexity Friction Stiction Examples Hewlett-Packard Thermal Inkjet Canon Bubblejet 1JOi, 102, 1304, J1107 Il 1,1114 1112, 1113, 15, 1J33, 134, 1335, 1336 Suitable for planar fabrication The effective area of the actuator becomes the membrane area t Fabrication complexity Actuator size Difficulty of integration in a VLSI process Device complexity May have friction at a pivot point 1982 Howkins USP 4,459,601 J05, 108, Il3, 128

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Rotary The actuator causes the rotation of some element, such a grill or impeller Rotary levers may be used to ircrase travel Small chip area requirements ~IIIIIll~-i----~lll~ll~__ll1111111~a~--- i ~I i 11 Bend Swivel Straighten Double bend The actuator bends when energized. This may be due to differential thenal expansion, piezoelectric expansion, magnetostricion, or other form of relative dimensional change.

A very small change in dimensions carl be converted to a large motion.

Requires the actuator to be made from at least two distinct layers, or to have a thermal difference across the actuator Inefficient coupling to the ink motion 1970 Kyser et a USP 3,946,398 1973 Stemme USP 3,747,120 1103, 1J09, IJ1O, 1 19 123, 1324, 125, 1129 1130, IJ31, 133, J34 1135 i 06 Shear Radial constriction Coil I utncoil Bow Push-Pull The actuator swivels around a central pivot.

This motion is suitable where there are opposite forces applied to opposite sides of the paddle, e.g. Lorenz force The actuator is normally bent, and straightens when energized.

The actuator bends in one direction when one element is energized, and bends the other way when another element is energized.

Energizing the actuator causes a shear motion in the actuator matcrial.

The actuator squeezes an ink reservoir, forcing ink from a consricted nozzle.

A coiled actuator uncoils or coils more tightly.

Ihe motion of the free end of the actuator ejects the ink.

The actuator bows (or buckles) in the middle when energized Two actuators control a shutter. One actuator pulls the shutter, and the other pushes it.

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Can be used with shape memory alloys wher e e austenic phase is planar One actuator can be used to power two nozzles.

Reduced chip size.

Not sensitive to ambient temperature r- Requires careful balance of stresses to ensure that the quiescent bend is accurate Difficult to make the drops ejected by both bend directions identical.

A small efficiency loss compared to equivalent single bend actuators.

1126, IJ32 J36, 1137, 338 i

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Allows operation where the net linear force on the paddle is zero Small chip area requirements Can incenase the effective travel of piezoelcrric actuators Relatively easy to fabricate single norzzls from glass tubing as macroscopic structures Not readily applicable to other actuator mechanisms High fore required Inefficient Difficult to integrate with VLSI processes S1985 Fishbeck USP 4,584,590 1970 Zoltan USP 3,683,212 Easy to fabricate as a planar VLSI process Small area required, therefore low cost Can increase the speed of travel Mechanically rigid 4 I-~~IIIIII11111111 Difficult to fabricate for non-planar devices Poor out-of-plane stiffness Maximum travel is constrained High force required i17, 1121, 1134, 1J35 1J16, IlS8, J127 ,118 111111~11 The structure is pinned at both ends, so has a high out-of-plane rigidity Not readily suitable for inkjets which directly push the ink 511CRR Curt inwards Curl outwards is Acoustic vibration r A set of actuators curl inwards to reduce the Good fl volume of ink that they enclose. the actu A set of actuators curl outwards, pressurizing Relativ ink in a chanber surrounding the acuators, and expelling ink from a nozzle in the chamber Multiple vanes enclose a volume of ink. These High ef simultaneously rotate, reducing the volume Small d between the vanes.

The actuator vibrates at a high frequncy. The acy from th uid flow to the region behind ator increases efficiency ely simple construction iciency hip area uator can be physically distant e ink i_ Design complexity J20, 1342 Relatively large chip area U143 High fabrication complexity Not suitable for pigmented inks Large area required for efficient operation at useful frequencies Acoustic coupling and crosstalk Complex drive circuitry Poor control of drop volume and position Various other tradeoffs are required to eliminate moving parts 1722 1993 Hadimioglu a al, EUP 550,192 1993 Elrod e al, EUP 572,220 Silverbrook, EP 077 1658 A2 and related patent applications Tone-jet q None In various inkjet designs the actuator does not move.

No moving parts Nozzle refill method I_ Nozze refill method Description Advantages Disadvantages Exampes Surface tension After the actuator is energized, it typically returns rapidly to its normal position This rapid return sucks in air through the nozzle opening.

The ink surface tension at the nozzle then exerts a small force rstoring the meniscus to a minimum area.

Ink to the nozzle chamber is provided at a pressure that oscillates at twice the drop ejection frequency. When a drop is to be ejected, the shutter is opened for 3 half cycles: drop ejection, actuator reurn, and refill.

Fabrication simplicity Operational simplicity Low speed Surface tension force relatively small compared to actuator force Long refill time usually dominates the total repetition rate Requires common ink pressure oscillator May not be suitable for pigmented inks Thermal inkjet Piezoelectric inkjet 130 -107, iJl0-iJ14 1316, 1320, 1122-1145 Shuttered oscillating ink pressure High speed Low actuator energy, as the actuator need only open or close the shutter, instead of ejecting the ink drop 108,1113, IJ15, IJ17 J118, U39, 1J21 1 L 1R3-U 111111 Refill actuator Positive ink pressure After the main actuator has ejected a drop a second (refill) actuator is energized The refill actuator pushes ink into the nozzle chamber.

'IThe refill actuator returns slowly, to prevent its return from mptying the chamber again.

The ink is held a slight positive pressure After the ink drop is ejected, the nozzle chamber fills quickly as surface tension and ink pressure both operate to refill the nozzle.

High speed, as the nozle is actively refilled High refill rate, therefore a high drop repetition rate is possible ~a 1 1 Requires two independent actuators per nozzle Surface spill must be prevented Highly hydrophobic print head surfaces are required 1309 Silvebrook, EP 0771 658 A2 and related patent applications Alternative for: 001-007, 1J0l-J14 1J16, 1120, 1J22-IJ45 Method of restricting back-flow through inlet ie riacK-now restricion method ecnipnton e Long inlet channel The ink inlet channel to the nozzle chamber is made long and relatively narrow, relying on viscous drag to reduce inlet back-flow.

Advantages Design simplicity Operational simplicity Reduces crosstalk Disadvantages Examples f Positive ink prssure

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The ink is under a positive pressure, so that in the quiscent state some of tdie ink drop alrmdy protrudes from the nozzle.

This reduces the pressure in the nozzle chamber which is required to eject a certain volurme of ink. The reduction in chaunber pressure results in a reduction in ink pushed out through the inlet Drop selection and separation forces can be reduced Fast refill time Restricts refill rate Ther May result in a relatively large chip area Piez Only partially eftfitive 1342, Requires a method (such as a nozzle rim or effective Silv hydrophtobizing, or both) to prevent flooding of the and ejection surface of te print hea& Poss follo 1114, IJ23- IJ44 mal inkjet oelectric inkjet IJ43 rbrook, EP 0771 658 A2 related patent applications ible operation of the wing: 1307, J109- 1l12 U 16, 120, 1122, -1134, UI36- IJ41 I- Baffle Fiexible flap rest inlet One or more baffles are placed in the inlet ink flow. When the actuator is energized, the rapid ink movement creates eddies which restrict the flow through the inlet The slower refill process is unrestricted, and does not result in eddies.

rics in this method recently disclosed by Canon, the expanding actuator (bubble) pushes on a flexible flap that resticts the inlet.

The refill rate is not as restricted as the long inlet method.

Reduces crosstalk Significantly reduces back-flow for edge-shooter thermal inkjet devices Additional advantage of ink filtration ink filter may be fabricated with no additional process steps Inlet filter Small inlet compared to nozzle A filter is located between the ink inlet and the nozzle chamber The filter has a multitude of small holes or slots, restricting ink flow. The filter also removes particles which may block the nozzle.

Design complexity May increase fabrication complexity Tektronix hot melt Piezoelectric print heads).

Not applicable to most inkjet configurations Increased fabrication complexity Inelastic deformation of polymer flap results in creep over extended use Restricts refill rate May result in complex construction Restrics refill rate May result in a relatively large chip area Only partially effective Requires separate refill actuator and drive circuit Requires careful design to minimize the negative pressure behind the paddle HP Termal Ink let Tektronix piezoelectric inkjet Canon 1304, 112, 1J24, 1327 1329, 1J30 The ink inlet channel to the nozzle chamber has a substantially smaller cross section than that of the nozzle, resulting in easier ink egress out of the nozzle than out of the inlet Design simplicity 1302, U37, I144 ii~l Inlet shutter The inlet is located behind the inkpushing surface A secondary actuator controls the position of a shutter, closing off the ink inlet when the main actuator is energized.

The method avoids the problem of inlet backflow by arranging the ink-pushing surface of the actuator between the inlet and the nozzle.

Increases speed of the ink-jet print head operation Back-flow problem is eliminated 1101, 1103, 1305, 1106 1J07, 1310, 1111, 114 1116, 1122, U123, 1325 Ui28, 1131, U32, I33 1334, 135, 1136, IJ39 1340, IJ41 -4 1 Part of the actuator The actuator and a wall of the ink chamber are Significant reductions in back-flow can Small increase in fabrication complexity J07, 1120, 326, 1138 moves to shut off the arranged so that the motion of the actuator be achieved inlet closes off the inlet. Compact designs possible Nozze actuator does In some configurations of ink jet, there is no Ink back-flow problem is eliminated None related to ink back-flow on actuation Silverrook, EP 0771 658 A2 not result in ink back- expansion or movement of an actuator which and related patent applications flow may cause ink back-flow through the inlet Valve-jet Tone-jet 1108, 13, 11 5, 1J!7 8, I19, 121 Nozze Clearing Method Nozzle Clearing Description Advantages Disadvantages Examples method Normal nozzle firing All of the nozzles are fired perioically, before No added complexity on the print head May not be sufficient to displace dried ink Most inkjet systeris the ink has a chance to dry. When not in use the 1101- I307, U09-J112 nozzles are sealed (capped) against air 1314, J16, 1J21 1122 The nozzle firing is usually perfouned during a 1323- IJ34, IJ36-U45 special clearing cycle, after first moving the print head to a cleaning station.

Extra power to ink n systems which hea. the ink, but do not boil it Can be highly effective if the heater is Requires higher drive voltage for clearing Silverbrook, EP 0771 658 A2 heater under normal situations, nozzle clearing can be adjacent to the nozzle May require larger drive transistors and related patentapplications achieved by over-powering the heater and boiling ink at the nozzle.

Rapid succession of The actuator is fired in rapid succession. In Does not require extra drive circuits on Effectiveness ds dep substantially upon the May be used with: actuator pulses some configurations, this may cause heat build- the print head configuration of the inkjet nozize 1101 -1307, 1109- I I up at the nozzle which boils the ink, dearing Can be readily controlled and initiated U14, IU16, 1120, 1J22 the nozzle. In other situations, it may cause by digital logic IJ23-125, IJ27-IJ34 sufficient vibrations to dislodge clogged 136-1145 nozzles, a_ I_ I Extra power to ink pushing actuator Acoustic resonance Where an actuator is not normally driven to the limit of its motion, nozzle clearing may be assisted by providing an enhanced drive signal to the actuator.

An ultrasonic wave is applial to the ink chamber, This wave is of an appropriate amplitude and frequency to cause sufficient force at the nozzle to clear blockages This is easiest to achieve if the ultrasonic wave is at a resonant frequency of the ink cavity.

A microfabricated plate is pushed against the nozzles. The plate has a post for every nozzle.

The array of posts The pressure of the ink is temporarily increased so that ink streams from all of the nzzles. This may be used in conjunction with actuator energizing.

A flexible 'blade' is wiped across the print head surface. The blade is usually fabricated from a flexible polymer, e.g. rubber or synthetic elastomer.

i A simple solution where applicable A high nozzle clearing capability can be achieved May be implemented at very low cost in systems which already include acoustic actuators High implementation cost if system does not ahlrady include an acoustic actuator Not suitable where there is a hard limit to actuator movement May be used with; [J03, IJ09, I16, IJ23, J24, U25, IJ27 1U29,1330, 1131, 132 339, IJ40, J41, IJ42 J143, 144, 1345 U08, 1113, 1315, 1317 1318, 1119, 121 Silverbrook, EP 0771 658 A2 and related patent applications Nozzle clearing plate Ink pressure pulse Print head wiper SCan clear severely clogged nozzles Accurate mechanical alignment is required Moving parts are required There is risk of damage to the nozzles Accurate fabrication is required May be effective where other methods cannot be used Effective for planar print head surfaces Low cost I Requires pressure pump or other pressure actuator Expensive Wasteful of ink May be used with all U series ink jets Many inkjet systems Difficult to use if print head surface is non-planar or very fragile Requires mechanical parts Blade can wear out in high volume print systems L. Separate ink boiling A separate heater is provided at the nozzle Can be effective where other nozzle Fabrication complexity Can be used with many U heater although the normal drop e-ction mechanism clearing methods cannot be used series ink jts does not require it. The heaters do not require Can be implemented at no additional individual drive circuits, as many nozzles can cost in some inkjet configurations be cleared simultaneously, and no imaging is required.

Nozzle plate construction Nozzle plate Description Advantages Disadvantages Examples construction Electroformed nicke A nozzle plate is separately fabricated from Fabrication simplicity High temperatures and pressures are required to bond Hewlett Packard Thermal elecrofonmed nickel, and bonded to the print nozzle plate Inkjet head chip. Minimum thickness constraints Differential thermal expansion Laser ablated or Individual nozzle holes are ablated by an No masks required Each hole must be individually formed Canon Bubblejet drilled poymer intense UV laser in a nozzle plate, which is Can be quite fast Special equipment required 1988 Sercel et al., SPIE, Vol.

typically a polymer such as polyimide or Some control over nozzle profile is Slow where there are many thousands of nozzles per 998 Excimer Beam polysulphone possible print head Applications, pp. 76-83 Equipment required is relatively low May produce thin burrs at exit holes 1993 Watanabe et aL, USP cost 5,208,604 Silicon micro- A separate nozzle plate is micromachined from High accuracy is attainable Two part construction K. Bean, IEEE Tranactions on machined single crystal silicon, and bonded to the print High cost Electron Devices, Vol. head wafer. Requires precision alignment No. 10, 1978, pp 1185-1195 Nozzles may be clogged by adhesive Xerox 1990 Hawkins e al, USP 4,899,181 I Glass capillaries Monolithic, surface micro-machined using VLSI lithographic processes Fine glass capillaries are drawn from glass tubing. This method has been used for making individual nozzles, but is difficult to use for bulk manufactring of print heads with thousands of nozzles.

The nozzle plate is deposited as a layer using standard VLSI deposition techniques. Nozzles are etched in the nozzle plate using VLSI lithography and.etching.

No expensive equipment required Simple to make single nozzles

I

Very small nozzle sizes are difficult to form Not suited for mass production High accuracy pnm) Monolithic Low cost Existing processes can be used Requires sacrificial layer under the nozzle plate to form the nozzle chamber Surface may be fragile to the touch 970 Zoltan USP 3,683,212 Silverbrok, EP 0771 658 A2 and related patent applications JO01, J302, 104, 111 1)12,1 17, 1318, 1U22, 1124, 1127, 1J28 IJ29, 130, IJ31, 1132 1J33, 1134, 136, 1137 1)38, IJ39, 1140, IJ41 IJ42, 1343, 1)44 103, 1305, I106,1107 1308, U109, 1110, 1I13 IJl4, U15, 1116, 119 ,121, 1U23, 125, 126 Ricoh 1995 Sekiya et al USP 5,412,413 1993 Hadimiaglu et ai EUP 550,192 1993 Elrod et al EUP 572,220 3 i -4 I Monolidtic, etched through substrate The nozzle plate is a buried etch stop in the wafer. Nozzle chambers are etched in the front of the wafer, and the wafer is thinned from the back side Nozzles are then etched in the etch stop layer.

High accuracy pmn) Monolithic Low cost No differential expansion Requires long etch times Requires a support wafer No nozzle plate Various methods have been tried to eliminate the nozzles etirely, to prevent nozzle clogging.

These include thermal bubble mechanisms and acoustic lens mechanisms Each drop ejector has a trough through which a paddle moves. There is no nozzle plate.

No nozzles to become clogged Reduced manufacturing complexity Monolithic Difficult to control drop position accurately Crosstalk problemsi Drop firing direction is sensitive to wicking.

'rough 1 I 1 48 Nozzle slit instead of The elimination of norle holes and No nozzles to become cogged Difficult to control drop position accurately 1989 Saito et a USP 4,799,068 individual enozles replacemenet by a slit encompassing many Crosstalk problems actuator positions reduces nozzle clogging, but increases crosstalk due to ink surface waves Drop ejection direction fjrtixon Direction Description Advantages Disadvantages Examples

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Edge ('edge shooter') Surface ('roof shooter') Through chip, forward ('up shooter') Through chip, reverse ('down shooter') Through actuator Ink flow is along the surface of the chip, and ink drops are ejected from the chip edge.

Ink flow is along the surface of the chip, and ink drops are ejected from the chip swuface, normal to the plane of the chip.

Ink flow is through the chip, and ink drops are ejected from the front surface of the chip.

Ink flow is through the chip, and ink drops are ejected from the rear surface of the chip.

Ink flow is through the actuator, which is not fabricated as part of the same substrate as the drive transistors.

Simple construction No silicon etching required Good heat sinking via substrate Mechanically strong Ease of chip handing No bulk silicon etching required Silicon can make an effective heat sink Mechanical strength High ink flow Suitable for pagewidth print High nozzle packing density therefore low manufacturing cost High ink flow Suitable for pagewidth print High nozale packing density therefore low manufacturing cost Nozzles limited to edge High resolution is difficult Fast color printing requires one print head per color Maximum ink flow is severely restricted Requires bulk silicon etching Canon Bubblejet 1979 Endo et al GB patent 2,007, 62 Xerox heater-in-pit 1990 Hawkins et at USP 4,899,181 'reon-jet Hewlett-Packard TU 1982 Vaught a a] USP 4,490,728 IJ02, IJ 11, 112, 1U20 1122 Silvexbrook, EP 0771 658 A2 and related patent applications U04, J1l7, 1118, 124 IJ27-IJ45 1301, 1303, 1105, U06 1307, 1J08, U109, 1310 1113, Ul4,1115, 116 1119,3 21, 123, 125 U126 Epson Stylus Tektronix hot melt piezoelectric ink jets Requires wafer thinning Requires special handling during manufacture Pagewidth print heads require several thousand connections to drive circuits Cannot be manufactured in standard CMOS fabs Complex assembly required Suitable for piezo lectric print heads -_111111~-- 1 _111~a m, Ink t-- Ink type Description Advantages Aqueous, dye Aqueous, pigment Methyl Ethyl Ketone

(MEK)

Water based ink which typically contains: water, dye, surfactant, humectant, and biocide.

Modenm ink dyes have high water-fastness, light fastness Water based ink which typically contains: water, pigment, surfahcan, humectant, and biocide.

Pigments have an advantage in reduced bleed, wicking and strikethrough.

Environmentally friendly Slow d No odor Conrrs 'antages rying ive on paper rikethrough s paper Irying ive at may clog noazles at may clog actuator mechanisms s paper Examples Environmentally friendly No odor Reduced bleed Reduced wicking Reduced strikethrough Very fast drying Prints on various substrates such as metals and plastics Most existing inkjets All J1 series ink jets Silverbrook, EP 0771 658 A2 and related patent applications 1102, I(04, 1J21, 126 UJ27, Silverbrook,,EP 0771 658 A2 and related patent applications Piezoelectric ink-jets 'hermal ink jets (with significant restrictions) All If series ink jets All I series ink jets MEK is a highly volatile solvent used for industrial printing on difficult surfaces such as aluminmm cans.

Odorous Flammable Alcohol (ethanol, 2-butanol, and others) Phase change (hot meit) Alcohol based inks can be used where die printer must operate at temperatures below the freezing point of water. An example of this is in-camera consumer photographic printing.

The ink is solid at room temperature, and is melted in the print head beforejetting. Hot melt inks are usually wax based, with a melting point around 80 After jetting the ink freezes almost instantly upon contacting the print medium or a transfer roller.

Fast drying Operates at sub-freezing temperatures Reduced paper cockle Low cost Slight odor Flammable i No drying time- ink instantly freezes on the print medium Almost any print medium can be used No paper cockle occurs No wicking occurs No bleed occurs No strikethrough occurs High viscosity Printed ink typically has a 'waxy' feel Printed pages may 'block' ink temperature may be above the curie point of permanent magnets Ink heaters consume power Long warm-up time Tektronix hot melt piezoelectric ink jets 1989 Nowak USP 4,820,346 All 1 series ink jets 11111~--- Microemulsion i YIIIII~- lllll_ Oil based inks are extensively used in offset printing. They have advantages in improved characteristics on paper (especially no wicking or cockle). Oil soluble dies and pigments are required.

A microenmulsion is a stable, self forming emulsion of oil, water, and surfactant. The characteristic drop size is less than 100 rm, and is determined by the preferred curvature of the surfactant.

I

High solubiliy medium for some dyes Does not cockle paper Does not wick through paper Stops ink beed High dye solubility Water, oil, and amphiphilic soluble dies can be used Can stabilize pigment suspensions ~1~-~11~11~111~

I

High viscosity: this is a significant limitation for use in inkjets, which usually require a low viscosity.

Some short chain and multi-branched oils have a sufficiently low viscosity.

Slow drying Viscosity higher than water Cost is slightly higher than water based ink High surfactant concentration required (around All 1J series ink jets All J series ink jets

I

ABSTRACT

An ink jet printhead assembly for a camera printer unit has a capping mechanism to prevent ink drying out employing mmbranes moved into place by a solenoid actuated arm.

Claims (8)

1. A pagewidth ink jet printhead assembly comprising a pagewidth ink jet printhead and a recapping mechanism for recapping the print head, the recapping mechanism comprising: a first stationary ferrous arm; a solenoid coil wrappendaround a portion of said ferrous arm; a second moveable arm located substantially adjacent said first arm and biased towards said print head; and a series of membranes attached to said second moveable arm, said membranes sealing said print head when in a non printing position; wherein said solenoid, when activated, causes said moveable ann to move away from the surface of said print head structure sufficiently to allow paper or film to be inserted between said membranes and said print head structure for the printing of ink thereon.

2. A print head assembly as claimed in claim 1 wherein said membranes are resiliently collapsible against the surface of said print head structure.

3. A print head assembly as claimed in claim I or claim 2 wherein said solenoid comprises an elongated winding of a current carrying wire which is wrapped around a protruding portion of said first arm, said elongated winding being substantially the length of said print head structure.

4. A print head assembly as claimed in any previous claim wherein said membranes comprise two mutually opposed elastomer trips running substantially the length of the ink jetting portions of said print head structure so as to surround said ink jetting portions, A print head assembly as claimed in any previous claim wherein said second movable an is biased against the surface of said print head structure.

6. A print head assembly as claimed in any previous claim wherein said solenoid is activated to move said second arn closely adjacent said first ann with a first level of current and said solenoid is retained whilst printing closely adjacent said first arm with a second substantially lower level of current. 7, A print head assembly as claimed in any previous claim wherein said assembly is utilized in a hand held camera device. a print head mechanism for printing out pictures on demand. The ink supply cartridge 42 includes a side aluminium strip 43 which is provided as a shear strip to assist in cutting images from a pater roll. A dial mechanism 44 is provided for indicating the number of "prints left". The dial mechanism 44 is snap fitted through a corresponding mating portion 46 so as to be freely rotatable, As shown in Fig. 6, the print head includes a flexible PCB strip 47 which interconnects with the print head and provides for control of the print head. The interconnection between the Flex PCB strip and an image sensor and print head chip can be via Tape Automated Bonding (TAB) Strips 51, 58. A moulded aspherical lens and aperture shim (Fig. 5) is also provided for imaging an image onto the surface of the image sensor chip normally located within eavity 53 and a light box module or hood 52 is provided for snap fitting over the cavity 53 so as to provide for proper light control. A series of decoupling capacitors eg. 34 can also be provided. Further a plug 45 (Fig. 7) is provided for re-plugging ink holes after refilling. A series of guide prongs eg, 55-57 are further provided for guiding the flexible PCB strip 47. The ink supply mechanism 40 interacts with a platten unit which guides print media under a printhead located in the ink supply mechanism. Fig. 8 shows an exploded view of the platten unit 60, while Figs. 9 and 10 show assembled views of the platten unit. The platten unit 60 includes a first pinch roller 61 which is snap fitted to one side of a platten base 62. Attached to a second side of the platten base 62 is a cutting mechanism 63 which traverses the platten by means of a rod 64 having a screwed thread which is rotated by means of cogged wheel 65 which is also fitted to the platten 62. The screwed thread engages a block 67 which includes a cutting wheel 68 fistened vi a a fastener 69. Also mounted to the block 67 is a counter actuator which includes a prong 7 1 The prong 71 acts to rotate the dial mechanism 44 of Fig. 6 un t here t u rn n l 1 i E 11 liiifil I ii 1 DI ID aan 1 -11 1 111-- I It can be seen that the preferred embodiment provides for a simple and inexpensive means of re-capping a printhead through the utilisation of a solenoid type device having a long rectangular form. Further, the preferred embodiment utilises minimal power in that currents are only required whilst the device is operational and additionally, only a low keeper current is required whilst the printhead is printing. Turning next to Fig. 13 and Fig. 14, Fig. 13 illustrates an exploded perspective of the ink supply cartridge 42 whilst Fig. 14 illustrates a close up sectional view of a bottom of the ink supply cartridge with the printhead unit in place. The ink supply cartridge 42 is based around a pagewidth printhead 102 which comprises a long slither of silicon having a series of holes etched on the back surface for the supply of ink to a front surface of the silicon wafer for subsequent ejection via a micro electro mechanical system. The form of ejectio an be many different forms such as those set out in the relevant provisional patent specifications of the attached appendix. In particular, the ink jet printing system set out in the provisional patent specification entitled "An Image Creation Method and Apparatus (138)" filed concurrently herewith is highly suitable. Of Course, many other inkjet technologies, a referred to the attached appendix, can also be utilised when constructing a printhead unit 102. The fimdamental requirement of the ink supply cartridge 42 being the supply of ink to a series of colour chamies etched through the back surface of the printhead 102. In the description of the preferred embodiment, it is assumed that a three colour printing process is to be utilised so as to provide full colour picture output. Hence, the print supply unit 42 includes three ink supply reservoirs being a cyan reservoir 104, a magenta reservoir 105 and a yellow reservoir 106. Each of these reservoirs is required to store ink and includes a corresponding sponge type material 107 109 which assists in stabilising ink within the corresponding ink channel and therefore preventing the ink from sloshing back and forth when the printhead is utilised in a handheld camera system. The reservoirs 104, 105, 106 are formed through the mating of first exterior plastic piece 110 mating with the second base piece il 1. At first end of the base piece i includes a series of air inlet 113 115. The air inlet leads to a corresponding winding channel which is hydrophobically treated so as to act as an ink repellent and therefore repel any ink that may flow along the air inlet channel. The air inlet channel firther takes a convoluted path firther assisting in resisting any ink flow out of the chambers 104 -106. An adhesive tape portion 117 is provided for sealing the channels within end portion 118. At the top end, there is included a series ofrefill holes for refilling corresponding ink supply chambers 104, 105,

106. A plug 121 is provided for sealing the refill holes. Turning now to Fig. 14, there is illustrated a close up perspective view, partly in section through the ink supply cartridge 42 of Fig. 13 when formed as a unit. The ink supply cartridge includes the three colour ink reservoirs 104, 105, 106 which supply ink to different portions of the back surface of printhead 102 which includes a series of apertures 128 defined therein for carriage of the ink to the front surface. The ink supply unit includes two guide walls 124, 125 which separate the various ink chambers and are tapered into an end portion abutting the surface of the printhead 102. The guide walls are further mechanically supported and regular spaces by a block portions eg. 126 which are placed at regular intervals along the length of the printhead supply unit. The block portions 126 leaving space at portions close to the back ofprinthead 102 for the flow of ink around the back surface thereof,. The printhead-supply unit is preferably formed from a-multi-part plastic injection mould and the mould pieces eg. 10, 11 (Fig. 1) snap together around the sponge pieces 107, 109. Subsequently,.a syringe type device can be inserted in the ink refill holes and the ink reservoirs filled with ink with the air flowing out of the air outlets 113 -115. Subsequently, the adhesive tape portion 117 and plug 121 are attached and the printhead td ted for operation capabilities. Subsequently, the ink supply cartridge 42 can be readily removed for refilling by means of removing the ink supply cartridge, performing a washing cycle, and then utilising the holes for the insertion of a refill syringe filled with ink for refilling the ink chamber before returning the ink supply cartridge 42 to a camera. -11 Turning now to Fig. 15, there is shown an example layout of the Image Capture aid Processing Chip (ICP) 48. The Image Capture and Processing Chip 48 provides most of the electronic functionality of the camera with the exception of the print head chip. The chip 48 is a highly integrated system. It combines CMOS image sensing, analog to digital conversion, digital image processing, DRAM storage, ROM, and miscellaneous control functions in a single chip. The chip is estimated to be around 32 mm using a leading edge 0 18 micron CMOS/DIRANlAPS process. The chip size and cost can scale somewhat with Moore's law, but is dominated by a CMOS active pixel sensor array 201, so scaling is limited as die sensor pixels approach the diffraction limit. The ICP 48 includes CMOS logic, a CMOS image sensor, DRAM, and analog circuitry. A very small amount of flash memory or other non-volatile memory is also preferably included for protection against reverse engineering. Alternatively, the ICP can readily be divided into two chips: one for the CMOS imaging array, and the other for the remaining circuitry. The cost of this two chip solution should not be significantly different than the single chip ICP, as the extra cost of packaging and bond-pad area is somewhat cancelled by the reduced total wafer area requiring the colour filter fabrication steps. The ICP preferably contains the following functions: Function megapixel image sensor Analog Signal Processors Image sensor column decoders Image sensor row decoders Analogue to digital Conversion (ADC) Column ADC's Auto exposure 12Mbits of DRAM DRAM Address Generator Colour interpolator Convolver Colour ALU Halftone matrix ROM Digital halftoning Print head interface 8 bit CPU core Program ROM Flash memory Scratchpad SRAM Parallel interface (8bit) Motor drive transistors Clock PLL JTAG test interface Test circuits Busses Bond pads -12- The CPU, DRAM, image sensor, ROM, Flash memory, Parallel interface, JTAG interface and ADC can be vendor supplied cores. The ICP is intended to run on 1.5V to minimise power consumption and allow convenient operation from two AA type battery cells. illustrates a ayout of the ICP 48. The ICP 48 is dominated by the imaging array 201, which consumes around 80% of the chip area. The imaging array is a CMOS 4 transistor active pixel design with a resolution of 1,500 x 1,000. The array can be divided into the conventional configuation, with two green pixels, one red pixel, and one blue pixel in each pixel group. There are 750 x 500 pixes groups in the imaging array. The latest advances in the field of image sensing and CMOS image sensing in particular can be found in the October, 1997 issue of IEEE Transactions on Electron Devices and, in particular, pages 1689 to 1968. Further, a specific implementation similar to that disclosed in the present application is disclosed in Wong et, al, "CMOS Active Pixel Image Sensors Fabricated Using a l.8V, 0.25gm CMOS Technology", IEDM 1996, page 915. The imaging array uses a 4 transistor active pixel design of a standard configuration. To minimise chip area and therefore cost, the image sensor pixels should be as small as feasible with the technology available. With a four transistor cell, the typical pixel size scales as 20 times the lithographic feature size. This allows a minimum pixel area of around 3.6nm x 3.6am. However, the photosite must be substantially above the diffraction limit of the lens. It is also advantageous to have a square photosite, to maximise the margin over the diffraction limited in both horizontal and vertical directions. in this case, the photosite can be specified as 2.5,im x 2.5gm, The photosite can be a photogate, pinned photodiode, charge modulation device, or other sensor. 'The four transistors are packed as an shape, rather than a rectangular region, to allow both the pixel and the photsite to be square. This reduces the transistor packing density slightly, increasing pixel size. However, the advantage in avoiding the diffraction limit is greater than the small decrease in packing density. T'he transistors also have a gate length which is longer than the minimum for the process technology. These have been increased from a drawn length of 0.18 micron to a drawn length of 0.36 micron. This is to improve the transistor matching by making the variations in gate length represent a smaller proportion of the total gate length. The extra gate length, and the shaped packing, mean that the transistors use more area than the minimum for the technology. Normally, around 81pm' would be required for rectangular packing. Preferably, 9,75p m has been allowed for the transistors. The total area for each pixel is 16grm, resulting from a pixel size of 4pm x 4pm. With a reslotution of 1,500 x 1,000, the area of the imaging array 10i is 6,000gm x 4,000.tm, or 24nmni a The presence of a colour image sensor on the chip affects the process required in two major ways: the CMOS fabrication process should be optimised to minimise dark current Colour filters are required. These can be fabricated using dyed photosensitive polyimides, reultiing in an added process complexity of three spin coatings, three photolithographic steps, three development steps, and three hardbakes. There are 15,00 analog signal processors (ASPs) 205, one for each of the columns of the sensor. The ASPs amplify the signal, provide a dark current-reference, sample and hold the signal, and suppress the fixed pattern noise There are 375 analog to digital converters 206, one for each four columns of the sensor array. These may be delta-sigma or successive approximation type ADC's A row of low column ADC's are used to reduce the conversion speed required, and the amount of analogue signal degradation incurred before the signal is converted to digital. This also eliminated the hot spot (affecting local dark current) and the substrate coupled noise that would occur if a single high speed ADC was used. Each ADC also has two four bit DAC's which trim the offset and scale of the ADC to further reduce FPN variations between columns. These DAC's are controlled by data stored in flash memory during chip testing, -13- The column select logic 204 is a 1:1500 decoder which enables the appropriate digital output of the ADC's onto the output bus. As each ADC is shared by four columns, the least significant two bits of the row select control 4 input analog multiplexers. A row decoder 207 is a 1:1000 decoder which enables the appropriate row of the active pixel sensor array. This S selects which of the !000 rows of the imaging array is connected to analog signal processors, As the rows are always accessed in sequence, the row select logic can be implemented as a shift register. An auto exposure system 208 adjusts the reference voltage of the ADC 205 in response to the maximum intensity sensed during the previous frame period. Data from the green pixels is passed through a digital peak detector. The peak value of the image frame period before capture (the reference frame) is provided to a digital to analogue 1 0 converter (DAC), which generates the global reference voltage for the column ADCs. The peak detector is reset at the beginning of the reference frame. The minimum and maximum values of the three RGB colour components are also collected for colour correction. The second largest section of the chip is consumed by a DRAM 210 used to hold the image. To store the 1,500 x 1,000 image from the sensor without compression, 1.5 Mbytes of DRAM 210 are required. This equals 12 Mbits, or slightly less than 5% of a 256 Mbit DRAM. The DRAM technology assumed is of the 256 Mbit generation implemented using 0.18pm CMOS. Using a standard 8F cell, the area taken by the memory array is 3.1 lnnm. When row decoders, column sensors, redundancy, and other factors are taken into account, the DRAM requires around 4mml. This DRAM 210 can be mostly eliminated if analog storage of the image signal can be accurately maintained in the CMOS imaging array for the two seconds required to print the photo. However, digital storage of the image is preferable as it is maintained withou degradation, is insensitive to noise, and allows copies of the photo to be printed considerably later. A DRAM address generator 211 provides the write and read addresses to the DRAM 210. Under normal operation, the write address is determined by the order of the data read from the CMOS image sensor 201. This will typically be a simple raster format. However, the data can be read from the sensor 201 in any order, if matching write addresses to the DRAM are generated. The read order from the DRAM 210 will normally simply match the requirements of a colour interpolator and the print head. As the cyan, magenta, and yellow rows of the print head are necessarily offset by a few pixels to allow space for nozzle actuators, the colours are not read from the DRAM simultaneously. However, there is plenty of time to read all of the data from the DRAM many times during the prnining process. This capability is used to eliminate the need for FIFOs in the print head interface, thereby saving chip area. All three RGB image components can be read from the DRAM each time colour data is required. This allows a colour space convere to provide a more sophisticated conversion than a simple linear RGB to CMY conversion. Also, to allow two dimensional filtering of the image data without requiring line buffers, data is re-read from the DRAM array. The address generator may also implement image effects in certain models of camera. For example, passport photos are generated by a manipulation of the read addresses to the DRAM. Also, image framing effects (where the central image is reduced)-image warps, and kaleidoscopic effects can all be generated by manipulating the read addresses of the DRAM. While the address generator 211 may be implemented with substantial complexity if effects are built into the standard chip, the chip area required for the address generator is small, as it consists only of address counters and a moderate amount of random logic. A colour interpolator 214 converts the interleaved patter of red, 2 x green, and blue pixels into RGB pixels. It consists of three 8 bit adders and associated registers. The divisions are by either 2 (for green) or 4 (for red and blue) so they can be implemented as fixed shifts in the output connections of the adders. -14- A convoiver 215 is provided as a sharpening filter which applies a small convolution kernel (5 x 5) to the red, green, and blue planes of the image. The convolution kernel for the green plane is different from that of the red and blue planes, as green has twice as many samples. The sharpening filter has five functions: To improve the colour interpolation from the linear interpolation provided by the colour interpolator, to a close approximation of a since interpolation. To compensate for the image "softening" which occurs during digitisation. To adjust the image sharpness to match average consumer preferences, which are typically for the image to be slightly sharper than reality. As the single use camera is intended as a consumer product, and not a professional photographic products, the processing can match the most popular settings, rather than the most accurate. To suppress the sharpening of high frequency (individual pixel) noise. The finction is similar to the "mnsharp mask" process. To antialias Image Warping. These functions are all combined into a single convolution matrix. As the pixel rate is low (less than I Mpixel per second) the total number of multiplies required for the thre colour channels is 56 million multiplies per second. This can be provided by a single multiplier. Fifty bytes of coefficient ROM are also required. A colour ALU 113 combines the functions of colour compensation and colour space conversion into the one matrix multiplication, which is applied to every pixel of the frame, As with sharpening, the colour correction should match the most popular settings, rather then the most accurate. A colour compensation circuit of the colour ALU provides compensation for the lighting of the photo. The vast majority of photographs are substantially improved by a simple colour compensation, which independently normalises the contrast and brightness of the three colour components. A colour look-up table (CLUT) 212 is provided for each colour component. These are three separate 256 x 8 SRAMs, requiring a total of 6,144 bits. The CLUTs are used as part of the colour correction process. They are also used for colour special effects, such as stochastically selected "wild colour" effects. A colour space conversion system of the colour ALU converts from the ROB colour space of the image sensor to the CMY colour space of the printer. The simplest conversion is a i's complement of the RGB data. However, this simple conversion assumes perfect linearity of both colour spaces, and perfect dye spectra for both the colour filters of the image sensor, and the ink dyes. At the other extreme is a tri-linear interpolation of a sampled three dimensional arbitrary transform table. This can effectively match any non-linearity or differences in either colour space. Such a system is usually necessary to obtain good colour space conversion when the print engine is a colour electrophotographic. However, since the non-linearity of a halfioned ink jet output is very small, a simpler system can be used, A simple matrix multiply can provide excellent results. This requires nine multiplies and six additions per contone pixel. However, since the contone pixel rate is low (less than I Mpixelsec) these operations can share a single multiplier and adder. The multiplier and adder are used in a colour ALU which is shared with the colour compensation function. Digital halfioning can be performed as a dispersed dot ordered dither using a stochastic optimised dither cell. -A halftone matrix ROM 116 is provided for storing dither cell coefficients. A dither cell size of 32 x 32 is adequate to ensure that the cell repeat cycle is not visible. The three colours cyan, magenta, and yellow are all dithered using the same cell, to ensure maximum co-positioning of the ink.dots. This minimises "muddying" of the mid-tones which results from bleed of dyes from one dot to adjacent dots while still wet. The total ROM size required is I KByte, as the one ROM shared by the halftoning units for each of the three colours. The digital halftoning used is dispersed dot ordered dither with tochastic optimised dither matrix. While dithering does not produce an image quite as "sharp" as error diffusion, it does produce a more accurate image with fewer artefacts. The image sharpening produced by error diffusion is artificial, and less controllable and accurate than "u'sharp mask" filtering performed in the contone domain. The high print resolution (1,600 dpi x 1,600 dpi) results in excellent quality when using a well formed stochastic dither matrix. Digital halftoning is performed by a digital halftoning unit 217 using a simple comparison between the contone information from the DRAM 210 and the contents of the dither matrix 216. During the halftone process, the resolution of the image is changed from the 250 dpi of the captured contone image to the 1,600 dpi of the printed image. Each contone pixel is converted to an average of 40.96 halftone dots, The ICP incorporates a 16 bit microcontroller CPU core 219 to run the miscellaneous camera functions, such as reading the buttons, controlling the motor and solenoids, setting up the hardware, and authenticating the refill station. The processing power required by the CPU is very modest, and a wide variety of processor cores can be used. As.the entire CPU program is run from a small ROM 220. Program compatibility between camera versions is not important, as no external programs are run. A 2 Mbit (256 Kbyte) program and data ROM 220 is included on chip. Most of this ROM space is allocated to data for outline graphics and fonts for specialty cameras. The program requirements are minor. The single most complex task is the encrypted authentication of the refill station. The ROM requires a single transistor per bit. A Flash memory 221 may be used to store a 128 bit authentication code. This provides higher security than storage of the authentication code in ROM, as reverse engineering can be made essentially impossible. The Flash memory is completely covered by third level metal, making the data impossible to extract using scanning probe microscopes or electron beams. The authentication code is stored in the chip when manufactured. At least two other Flash bits are required for the authentication process: a bit which locks out reprogramming of the authentication code, and a bit which indicates that the camera has been refilled by an authenticated refill station. The flash memory can also be used to store FPN correction data for the imaging array. Additionally, a phase locked loop resealing parameter is stored provided for scaling the clocking cycle to an appropriated correct time. The clock frequency does not require crystal accuracy since no date functions are provided. To eliminate the cost of a crystal, an on-chip oscillator with a phase locked loop 124 is used. As the frequency of an on-chip oscillator is highly variable from chip to chip, the frequency ratio of the oscillator to the PLL is digitally trimmed during initial testing. The value is stored in Flash memory 121. This allows the clock PLL to control the inkjet heater pulse width with sufficient accuracy. A scratchpad SRAM is a small static RAM 222 with a 6T cell. The scratch pad provided temporary memory for the 16 bit CPU, 1024 bytes is adequate. A print head interface 223 formats the data correctly for the print head. The print head interface also provides all of the timing signals required by the print head. These timing signals may vary depending upon temperature, the number of dots printed simultaneously, the print medium in the print roll, and the dye density of the ink in the print roll. The following is a table of external connections to the print head surface: Connection Function Pins Databits[0-7] Independent serial data to the eight segnents of the print head. 8 BitClock Main data clock for the print head. 1 ColourEnable[0-2] Independent enable signals for the CMY actuators, allowing 3 different pulse times for each colour. -16-- Banknable{0- Allows either simutaneous or interleaved actuation of two banks of 2 nozzles. This allows two different print speedipower consumption tradeoffs. NozzleSelect(0-4] Selects one of 32 banks of nozzles for simultaneous actuation. ParalielXferClock Loads the parallel transfer register with the data from the shift registers. I Total The print head utilised is composed of eight identical segments, each 1.25cm long. There is no connection between the segments on the print head chip. Any connections required are made in the external TAB bonding film, which is double sided. The division into eight identical segments is to simplify lithography using wafer steppers. The segment width of ,25cm fits easily into a stepper field. As the print head chip is long and narrow (10cm x 0.3mm), the stepper field contains a single segment of 32 print head chips. The stepper field is therefore 1,25cm x 16cm., An average of four complete print heads are patterned in each wafer step. A single BitClock output line connects to all 8 segments on the print head. The 8 DataBits lines lead one to each segment, and are clocked in to the 8 segments on the print head simultaneously (on a BitClock pulse). For example, dot 0 is transferred to segment, dot 750 is transferred to segment;, dot 1500 to segment 2 etc simultaneously. The ParallelXferClock is connected to each of the 8 segments on the print head, so that on a single pulse, all segments transfer their bits at the same time. The NozzleSelect, BankEnable and ColorEnable lines are connected to each of the 8 segments, allowing the print head interface to independently control the duration of the cyan, magenta, and yellow nozle energizing pulses. Registers in the Print Head Interface allow the accurate specification of the pulse duration between 0 and 6 ms, with a typical duration of 2 ms to 3 ms. A parallel interface 125 connects the ICP to individual static electrical signals. The CPU is able to control each of these connections as memory mapped IO via a low speed bus. The following is a table of connections to the parallel interface: Connection Direction ins Paper transport stepper motor Output 4 Capping solenoid Output 1 Copy LED Output 1 Photo button Input 1 Copy button Input 1 Total 8 A serial interface is also included to allow authentication of the refill station. This is included to ensure that the cameras are only refilled with paper and ink at authorized refill stations, thus preventing inferior quality refill industry from occurring. The camera must authenticate the refill station, rather than the other way around. The. -17- secure protocol is communicated to the refill station via a serial data connection. Contact can be made to four gold plated spots on the iCP/print head TAB by the refill station as the new ink is injected into the print head. Seven high current drive transistors eg. 227 are required Four are for the four phases of the main stepper motor two are for the guillotine motor, and the remaining transistor is to drive the capping solenoid. These transistors are allocated 20,000 square microns (600,000 F) each. As the transistors are driving highly inductive loads, they must either be turned off slowly, or be provided with a high level of back EMF protection. If adequate back EMF protection cannot be provided using the chip process chosen, then external discrete transistors should be used. The transistors are never driven at the same time as the image sensor is used. This is to avoid voltage fluctuations and hot spots affecting the image quality. Further, the transistors are located as far away from the sensor as possible. A standard JTAG (Joint Test Action Group) interface 228 is included in the ICP for testing purposes and for interrogation by the refill station. Due to the complexity of the chip, a variety of testing techniques are required, including BIST (Built In Self Test) and functional block isolation. An overhead of 10% in chip area is assumed for chip testing circuitry for the random logic portions. The overhead for the large arrays them image sensor and the DRAM is smaller. The JTAG interface is also used for authentication of the refill station. This is included to ensure that the cameras are only refilled with quality paper and ink at a properly constructed refill station, thus preventing inferior quality refills from occurring. The camnera must authenticate the refill station, rather than vice versa. The secure protocol is communicated to the refill station during the automated test procedure. Contact is made to four gold plated spots on the ICP/print head TAB by the refill station as the new ink is injected into the print head. Fig. 16 illustrates rear view of the next step in the construction process whilst Fig. 17 illustrates a front camera view, Turning now to Fig. 16, the assembly of the camera system proceeds via first assembling the ink supply mechanism 40. The flex PCB is intercomnected with batteries only one 84 of which is shown, which are inserted in the middle portion of a print roll 85 which is wrapped around a plastic former 86. An end cap 89 is provided at the other end of the print roll 85 so as to fasten the print roll and batteries firmly to the ink supply mechanism. The solenoid coil is interconnected (not shown) to interconnects 97, 98 (Fig. 8) which include leaf spring ends for interconnection with electrical contacts on the Flex PCB so as to provide for electrical control of the solenoid. Turning now to Figs. 17 -19 the next step in the construction process is the insertion of the relevant gear chains into the side of the camera chassis. Fig. 17 illustrates a front camera view, Fig. 18 illustrates a back side view and Fig. 19 also illustrates a back side view. The first gear chain comprising gear wheels 22, 23 are utilised for driving the guillotine blade with the gear wheel 23 engaging the gear wheel 65 of Fig. 8. The second gear chain comprising gear wheels 24, and 26 engage one end of the print roller 61 of Fig. As best indicated in Fig. 18, the gear wheels mate with corresponding buttons on the surface of the chassis with the gear wheel 26 being snap fitted into corresponding mating hole 27, Next, as illustrated in Fig. 20, the assembled platten unit is then inserted between the print roll 85 and aluminium cutting blade 43. Turning now to Fig. 2 1 by way of illumination, there is illustrated the electrically interactive components of the camera system. As noted previously, the components are based around a Flex PCB board and include a TAB film 58 which interconnects the printhead 102 with the image sensor and processing chip 51. Power is supplied by two AA type batteries 83, 84 and a paper drive stepper motor 16 is provided in addition to a rotary guillotine motor An optical element 31 is provided for snapping into a top portion of the chassis 12. The optical element 31 includes portions defining an optical view finder 32, 33 which are slotted into mating portions 35, 36 in view finder channel 37. Also provided in the optical element 31 is a lensing system 38 for magnification of the prints left number in addition to an optical pipe element 39 for piping light from the LED 5 for external display. -18- Turning next to Fig. 22, the assembled unit 90 is then inserted into a front outer case 91 which includes button 4 for activation of printouts. Turning now to Fig. 23, next, the unit 92 is provided with a snap-on back cover 93 which includes a slot 6 and copy print button 7. A wrapper label containing instructions and advertising (not shown) is then wrapped around the outer surface of the camera system and pinch clamped to the cover by means of clamp strip 96 which can comprise a flexible plastic or rubber strip. Subsequently, the preferred embodiment is ready for use as a one time use camera system that provides for instant output images on demand. It will be evident that the preferred embodiment further provides for a refillable camera system. A used camera can be collected and its outer plastic cases removed and recycled. A new paper roll and batteries can be added and the ink cartridge refilled. A series of automatic test routines can then be carried out to ensure that the printer is properly operational. Further, in order to ensure only authorised refills are conducted so as to enhance quality, routines in the on-chip program ROM can be executed such that the camera authenticates the refilling station using a secure protocol. Upon authentication, the camera can reset an internal paper count and an external case can be fitted on the camera system with a new outer label. Subsequent packing and shipping can then take place. It will be further readily evident to those skilled in the art that the program ROM can be modified so as to allow for a variety of digital processing routines. In addition to the digitally enhanced photographs optimised for mainstream consumer preferences, various other models can readily be provided through mere re-progranuning of the program ROM. For example, a sepia classic old fashion style output can be provided through a remapping of the colour mapping function. A further alternative is to provide for black and white outputs again through a suitable colour remapping algorithm. Minimumless colour can also be provided to add a touch of colour to black and white prints to produce the effect that was traditionally used to colourize black and white photographs. Further, passport photo output can be provided through suitable address remappings within the address generators. Further, edge filters can be utilised as is known in the field of image processing to produce sketched art styles. Further, classic wedding borders and designs can be placed around an output image in addition to the provision of relevant clip arts. For examppe, a wedding style camera might be provided. Further, a panoramic mode can be provided so as to output the well known panoramic format of images. Further, a postcard style output can be provided through the printing of postcards including postage on the back of a print roll surface. Further, clip arts can be provided for special events such as Holoween, Christmas etc. Further, kaleidoscopic effects can be provided through address remappings and wild colour effects can be provided through remapping of the colour look-up table. Many other forms of special event cameras can be provided for example, cameras dedicated to the Olympics, movie tie-ins, advertising and other special events. The operational mode of the camera can be prograummed so that upon the depressing of the take photo a first image is sampled by the sensor array to determine irrelevant parameters. Next a second image is again captured which is utilised for the output. The captured image is then manipulated in accordance with any special requirements before being initially output on the paper roll. The LED light is then activated for a predetermined time during which the DRAM is refreshed so as to retain the image. If the print copy button is depressed during this predetermined time interval, a further copy of the photo is output. After the predetermined time interval where no use of the camera has occurred, the onboard CPU shuts down all power to the camera system until such time as the take button is again activated, in this way, substantial power savings can be realised. Jet Technologies The embodiments of the invention us an inkjet printer type device. Of course many different devices could be used However presently popular ink jet printing technologies are unlikely to be suitable. The most significant problem with thermal inkjet is power consumption. This is approximately 100 times that required for high speed, and st ms from the energy-inefficient means of drop ejection. This involves the rapid boiling of water -19- to produce a vapor bubble which expels the ink. Water has a very high heat capacity, and must be superheated in thermal inkjet applications. This leads to an efficiency of around 0.02%, from electricity input to drop momentum (and increased surface area) out. The most significant problem with piezoelectric inkjet is size and cost. Piezoelectric crystals have a very small deflection at reasonable drive voltages, and therefore require a large area for each noszze. Also, each piezolectric actuator must be connected to its drive circuit on a separate substrate. This is not a significant problem at the current limit of around 300 nozzles per print head, but is a major impediment to the fabrication of pagewide print heads with 19,200 nozzles. Ideally, the inkjet technologies used meet the stringent requirements of in-camera digital color printing and other high quaity, high speed, low cost printing applications. To meet the requirements of digital photography, new inkjet technologies have been created. The target features include: low power (less than 10 Watts) high resolution capability (1,6X) dpi or more) photographic quality output low manufacturing cost small size (pagewidth times minimum cross section) high speed 2 seconds per page) ART-END All of these features can be met or exceeded by the inkjet systems described below with differing levels of difficulty. different inkjet technologies have been developed by the Assignee to give a wide range of choices for high volume manufacture. These technologies form part of separate applications assigned to the present Assignee as set out in the table below. The inkjet designs shown here are suitable for a wide range of digital printing systems, from battery powered one- rime use digital cameras, through to desktop and network printers, and through to comiercial printing systems For ease of manuficmee using standard process equipment, the print head is designed to be a monolithic 0.5 micron CMOS chip with MEMS post processing. For color photographic applications, the print head is 100 mm long, with a width which depends upon the inkjet type. The smallest prit head designed is U38, which is 0.35 mm wide, giving a chip area of square mm. The print heads each contain 19,200 nozzles plus data and control circuitry. Ink is supplied to the back of the print head by injection molded plastic ink channels. The molding requires 50 micron features, which can be created using a lithographically micmrmachined insert in a standard injection molding tool. Ink flows through holes etched through the wafer to the nozzle chambers fabricated on the fi-ont surface of the wafer. The print head is connected t tthe camera circuitry by tape automated bonding. Cross-Referenced Applications The following table is a guide to cross-referenced patent applications filed concurrently herewith and discussed hereinafter with the reference being utilized in subsequent tables when referring to a particular case: Docket No. Reference Title JO1 US i01 Radiant Plunger Ink Jet Printer U02US J102 Electrostatic Ink Jet Printer 1J03US IJ03 Planar Thenmolastic Bend Actuator Ink Jet J104US IJ04 Stacked Electrostatic Ink Jet Printer IJOSUS J05 Reverse Spring Lever Iak Jet Printer U06US J06 Paddle Type Ink Jet Printer U07US IJ07 Permanent Magnet Electromagnetic lnk Jet Printer IJ08US I08 Planar Swing Grill Electromagnetic Ink Jet Printer 0JO9US 1109 Pump Action Refill Ink Jet Printer 1U1OUS 110 Pulsed Magnetic Field Ink Jet Printer U13lUS Ill1 Two Plate Reverse Firing Electromagnetic Ink Jet Printer Ul2US 1112 Linear Stepper Actuator Ink Jet Printer 1113US 1113 Gear Driven Shutter Ink Jet Printer U114US I 14 Tapered Magnetic Pole Electromagnetic Ink Jet Printer 1115 Linear Spring Electromagnetic Grill Ink Jet Printer IJ 16US 1l16 Lorenz Diaphragm Electromagnetic Ink Jet Printer 11 TUIS 111 FiFE Surface Shooting Shuttered Oscillating Pressure Ink Jet Printer 1118US 1118 Buckle Grip Oscillating Pressu Ink Jet Printer 119US 1119 Shutter Based Ink Jet Printer IJ20 Curling Calyx Thermoelastic Ink Jet Printer IJ21 US 1121 Thermal Actuated nk Jet Printer IJ22US 1122 Iris Motion Ink Jet Printer 123US 123 Direct Firing Thennal Bend Actuator Ink Jet Printer LI24US 1124 Conductive PTFE Ben Activator Vented Ink Jet Printer [125 Magnetostrictive Ink Jet Printer J26US U26 Shape Memory Alloy Ink Jet Printer IJ27US 1327 Buckle Plate Ink Jet Printer IJ28US 1328 Thermal Elastic Rotary Impeller Ink Jet Printer IJ129US 129 Thenmoelastic Bend Actuator Ink let Printer )31US 1130 Thermoelastic Bend Actuator Using PTFE and Corrugated Copper Ink Jet Printer IJ31US I31 Bend Actuator Diret Ink Supply Ink Jet Printer U32US IJ32 A High Young's Modulus Thermolastic ink Jet Printer 1J33US 1U33 Thermally actuated slotted chamber wall inkjet printer IJ34US 134 Ink Jet Printer having a thenrmal actuator comprising an external coiled spring IJ35 Trough Container Ink Jet Printer U36US 1136 Dual Chamber Single Vertical Actuator Ink Jet U37US U37 Dual Nozzle Single Horizonta Fukinrum Actuator Ink Jet 1J38US U38 Dual Nozzle Single Horizontal Actuator ink Jet 139US IJ39 A single bend actuator cupped paddle inkjet printing devime 140F A thermally actuated ink jet printer having a series of thermal actuator units IJ41US U -41 A thermally actuated inkjet printer including a tapered heater element IJ42US IJ42 Radial Back-Curling Thermoelastic Ink Jet IJ43US IJ43 Inverted Radial Back-Curling Thermnoelastic Ink Jet IJ44US 1144 Surface bend actuator vented ink supply inkjet printer 14S Coil Actuated Mlagnetic Plate Ink Jet Printer Ink Jet Printing A large nunmber of new forms of ink jet printers have been developed to facilitate alternative inkjet technologies for the image processing and data distribution system. Various combinations of ink jet devices can be included in printer devices -21 incorporated as pa of the present invention. Australian Provisional Patent Applications relating to these ink jets which are specifically incorporated by cross reference include: Australian Filing Date Title Provisional Number P08066 15-Jul-97 Image Creation Method and Apparatus (IJ0 1)-WO99/03680 P08072 15-Jul-97 Image Creation Method and Apparatus (IJ02) -W099/03680 P08040 15-Jul-97 Image Creation Method and Apparatus (1103) -W99/03681 P8071 15-Jul-97 Image Creation Method and Apparatus (104) -WO99/03680 P08047 15-Jul-97 Image Creation Method and Apparatus (105) -WO99/03680 P08035 15-Jul-97 Image Creation Method and Apparatus (1506) -WO99103680 P08044 15-Jul-97 Image Creation Method and Apparatus (I107) -WO99/03680 PO8063 15-Jul-97 Image Creation Method and Apparatus (1108) -WO99/03680 P08057 15-Jul-97 Image Creation Method and Apparatus (U09) -WO99/0368 I P08056 15-Jul-97 Image Creation Method and Apparatus (IJ10) -WO99/0368 1 PO806 15-Jul-97 Image Creation Method and Apparatus (I311) -W099/03680 P08049 15-Jul-97 mage Creation Method and Apparatus (J12) -WO99/03680 P08036 15-Jul-97 Image Creation Method and Apparatus (113) -W099/03680 P08048 IS-Jul-97 Image Creation Method and Apparatus (IJ14) -WO99/03680 P08070 15-Jul-97 Image Creation Method and Apparatus (1J15) -WO99/03680 P08067 15-Jul-97 Image Creation Method and Apparatus (1116) -WO99/03680 P08001 15-Jul-97 Image Creation Method and Apparatus (Ul7) -WO99/0368I P08038 15-Jul-97 Image Creation Method and Apparatus (1118) -WO99/03681 P08033 15-Jul-97 Image Creation Method and Apparatus (1119)-US 6,254,220 P08002 15-Jul-97 Image Creation Method and Apparatus (1120) -WO99103681 P08068 1S-Jul-97 Image Creation Method and Apparatus (1321) -WO9910368 1 P08062 15-Jul-97 Image Creation Method and Apparatus (1322) -WO9903681 P08034 15-Jul-97 Image Creation Method and Apparatus (1)23) -WO99/03681 P08039 15-Jul-97 Image Creation Method and Apparatus (1124) -WO9910368 1 P08041 15-Jul-97 Image Creation Method and Apparso (025) -W099/03680 P08004 15-Jul-97 Image Creation Method and Apparatus (126) -W09903680 P08037 15-Jul-97 Image Creation Method and Apparatus (1127) -W099/036 81 P08043 15-Jul-97 Image Creation Method and Apparatus (128) -WO99/0368 I P08042 15-Jui-97 Image Creation Method and Apparatus (1129) -WO99/03681 P08064 15-Jul-97 Image Creation Method and Apparatus (1130) -WO99/03681 P09389 23-Sep-97 Image Creation Method and Apparatus (1131) -W099/03681 P09391 23-Sep-97 inage Creation Method and Apparatus (132)-US6,234,609 PP0888 12-Dec-97 Image Creation Method and Apparatus (1133) -WO99/0368 I PP0891 12-.Dec-97 Image Creation Method and Apparatus (134) -WO99/0368 I 12-Dec-97 Image Creation Method and Apparatus (IJ35) -WO99/03681 PPO873 12-Dec-97 Image Creation Method and Apparatus (i36) -WO99/0368 I PP0993 12-Dec-97 Image Creation Method and Apparatus (IJ37)-US 6,247,791 22 PP0890 12-Dec-97 Image Creation Method and Apparatus (IJ38) -US 6,336,710 PP 1398 19-Jan-98 An Image Creation Method and dApparatus (1339) -WO99103681 PP2592 25-Mar-98 An Image Creation Method and Apparatus (U140) -WO99/03681 PP2593 25-Mar-98 Image Creation Method and Apparatus (IJ41) WO99/03681 PP3991 9-Jun-98 Image Creation Method and Apparatus (142)-US 6,283,581 PP3987 9-Ju9-98 Image Creation Method and Apparatum (IJ43) -WO99/03681 PP3985 9-Jun-98 Image Creation Method and Apparatus (144) -WO99/03681 PP3983 9-Jun-98 Image Creation Method and Apparatus (1J45) -WO99/03681 I InkJet Manufacturing Further, the present application may utilize advanced semiconductor fabrication techniques in the construction of S large arrays of inkjet prinria. Suitable manufacturing techniques are described in the following Australian provisional patent specifications incorporated here by cross-reference: Australian Filing Date Title Provisional Number P07935 15-Jul-97 A Method of Manufacture of an Image Creation Apparatus (IJMOI) -WO99/03680 P07936 15-Jul-97 A Method of Manufacture of an Image Creation Apparatus (IJM02) -WO99/03680 P07937 15-Jul-97 A Method of Manufacture of an Image Creation Apparatus (IDM03) W099/03681 P08061 15-Jul-97 A Method of Manufacture of an Image Creation Apparatus (D1M04) -WO99/03680 P08054 15-Jul-97 A Method of Manufacture of an Image Creation Apparatus (IM05) -WO99/03680 P08065 15-Jul-97 A Method of Manufacture of an Image Creation Apparatus (IJM06) WO99/03680 P08055 15-Jul-97 A Method of Manufacture of an Image Creation Apparatus (IJMO7) -W099/03680 PO-053 15-Jul-97 A Method of Manufacture of an Image Creation Appartus (IJMOS) WO99/03680 P08078 15-Jul-97 A Method of Manufacture of an Image Creation Apparatus (IJM09) -WO99/03681 P07933 15-Jul-97 A Method of Manufacture of an Image Creation Apparatus (IJM 1O) -WO99/03681 P07950 15-Jul-97 A Method of Manufacture of an Image Creation Apparatus (M I1) WO9903680 P07949 15-Jul-97 A Method of Manufacture of an Image Creation Appai-tws (UM 12) -WO99/03680 P08060 15-Jul-97 A Method of Manufacture of an Image Creation Apparatus (UM 13) WO99/03680 P08059 15-Jul-97 A Method of Manufacture of an Image Creation Apparatus (tJM 14) -W099/03680) P08073 15-Jul-97 A Method of Manufacture of an Image Creation Apparatus (IM 15) -WO99/03680 P08076 15-Jul-97 A Method of Manufacture of an Image Creation Apparatus (UM 16) -WO9903680 P08075 15-Jul-97 A Method of Manufacture of an Image Creation Apparatus (UM 17) W 099/03681 PO8079 15-Jul-97 A Method of Manufacture of an Image Creation Apparatus (IM 18) -W099/0368 I P08050 15-Jul-97 A Method of Manufacture of an Image Creation Apparatus (iM 19) -WO99/03681 P08052 15-Jul-97 A Method of Manufacture of an Image Creation Apparatus (IJM20) -WO99/03681 P07948 15-Jul-97 A Method of Manufacture of an Image Creation Apparatus (IJM2 1) -WO99/03681 P07951 15-Jul-97 A Method of Manufacture of an Image Creation Apparatus (1JM22) -W099/03681 P08074 15-Jul-97 A Method of Manufacture of an Image Creation Apparatus (1JM23) -W099103681 P07941 15-Jul-97 A Method of Manufacture of an Image Creation Apparatus (tJM24) -WO99/03681 P08077 15-Jul-97 A Method of Manufacture of an Image Creation Apparatus (IJM25) -WO99/03680 PO8058 15-Jul-97 A Method of Manufacture of an Image Creation Apparatus (1JM26) -WO99/03680 P08051 15-Jul-97 A Merthod of Manufacture of an Image Creation Apparatus (IJM27) -WO99/03681 P08045 15-Jul-97 A Method of Manufacture of an Image Creation Apparatus (IJM28) -WO99036 81 P07952 15-Jul-97 A Method of Manufacture of an Image Creation Apparatus (IJM29) -WO9903681 P08046 15-Jul-97 A Method of Manufacture of an Image Creation Apparatus (IJM30) -WO99/03681 P08503 11-Aug-97 A Method of Manufacture of an Image Creation Apparatus (UM30a) -WO99/03681 P09390 23-Sep-97 A Method of Manufacture of an Image Creation Apparatus (DM31) -WO9903681 P09392 23-Sep-97 A Method of Manufiacure of an Image Creation Apparatus (IdM32) -WO99/03681 PP0889 12-Dec-97 A Method of Manufacture of an Image Creation Apparatus (DM35) -WO99/03681 PP0887 12-Dec-97 A Method of Manufacture of an Image Creation Apparatus (1JM36)-USSN 09/122,801 P0882 12-Dec-97 A Method of Manufacture of an Image Creation Apparatus (IJM37) -WO99/03681 PP0874 12-Dec-97 A Method of Manufacture of an Image Creation Apparatus (IJM38) -WO99/03681 PP1396 19-Jan-98 A Method of Manufacture of an Image Creation Apparatus (NM-39) -WO99/03681 PP2591 25-Mar-98 A Method of Manufacture of an Image Creation Apparatus (JM4 1) -WO99/03681 PP3989 9-Jun-98 A Method of Manufacture of an Image Creation Apparatus (JM40) -WO99/03681 PP3990 9-Jun-98 A Method of Manufacture of an Image Creation Apparatus (1JM42) -WO99/0368 1 PP3986 9-Jun-98 A Method of Manufacture of an Image Creation Apparatus (JIM43) -WO99/03681 PP3984 9-Jun-98 A Method of Manufacture of an Image Creation Apparatus (IM44) -WO99/03681 PP3982 9f-Jun-98 A Method of Manufacture of an Image Creation Apparatus (IJM45) -WO99/03680 Fluid Supply Further, the present application may utilize an ink delivery system to the ink jet head Delivery systems relating to the S supply of ink to a series of ink jet nozzles are described in the following Australian provisional patent specifications, the disclosure of which are hereby incorporated by cross-refence: Australian Filing Date Title Provisional Number P08003 15-Jul-97 Supply Method and Apparatus (F1) -WO99/03681 P8005 15-Jul-97 Supply Method and Apparatus -WO99/04368 P09404 23-Sep-97 A Device and Method (F3)-USSN 09/113,101 MEMS Technology Further, the present application may utilize advanced semiconductor microclectromnchanical techniques in the construction of large armays of ink jet printers. Suitable microelectromechanical techniques are described in the following Australian provisional patent specifications incorporated here by cross-referenc Australian Filing Date Title Provisional Number P07943 15-Jul-97 A device (MEMSOI) -W 99/03681 PO8006 15-Jul-97 A device (MEMSO2) -WO99/03681 24- P08007 15-Jul-97 A device (IMEMSO3) -W099/03681 P0800)8 15-Jul-97 A device (NIEMSO43 -W099031681 P0801 0 15-4u-97 A device (MEMSO5) -W0991L681 P08011 15-Jul-97 A device (MEMS06) -W099/0368 I P07947 15-Jul-97 A device (MEMSO7) -W099,'0368 I P07945 1 5-Jul-97 A device (MEMISOS) -W0?.9/0368 1 P07944 151-7A device (M EM 809) -W099/10368 I P07946 1 5-Jul-97 A device (MEMS 10) -W099,/0368 I P09393 2 3-Sem-97 A Device and Method (MEMS 11) -W099/0368 I PP0875 12-Dec.-97 A Device (MEMS 12) -W099/0368I PP0894 l 2-Dec-97 A Device and Method (M EMS 13) -W099/03 681I JR Technologies Further, the present application may include the utilization of a disposable camer system such as those described in dte following.Australian provisionali patent specifications incorporated here bycosrfrne Australian Filing Date Title Provisional PP0895 12-Dec-97 An Image Creation Method and Apparatus (IROl1) -W099/0455 1 220870 12-Dec-97 A Device and Methd (11(02) W099/04551 PP0869 12-Dec-97 A Deviceand Method (11(04) W099/04551 220887 12-Dec-97 Image Creation Method and Apparatus (11(05) W099,104551I P20885 *2-Dec-97 An Image Production System (11(06) W099/0455 I PP0884 12-Dec-97 image Creation Method and Apparatus (IRIO0) W09910455 I PP0886 12-Dec-97 Imiage Crea.tion Method and Apparatus (11412) W099/04551 PP0871 12-Dec-97 A Device and Method (11(13) W099!04551I PF0876 12-lDec-97 An Image Processing Methiod and Apparatus (1K 14) W099i0455 I 220878 127-Dec -97 A Device and Method (T1(1) W099104551 2P0879 12-Dec-97 A Device and Method (IRIS) W099/04551 PP088(3 12-Dec-97 jA Device and Method (11(19) W099!0455 I P20880 12-Dec-97 JA Device and Method (11(20) W099/04551 220881 12-Dec-97 [A Device and Method (11(21) W099V/04551 DotCard Technologies o Further, the present application may include the utlization of a data distribution system such as Chat described in the following Australian pro-visional patent specifications incorporated here by cosrfrne Austalian Filing Datte Title Provisional NumberI 2R30-AU PP2370 I16-Mar-98 jData Processing Method and Apparatus (Dot0l)-USSN 09/112,781 PP2371 i6-Mar-98 Data Processing Method and Apparatus (Dot02-iUSSN 09/113,052 I Artcamn Technologies Further, the present application may include the utilization of camera and data processing techniques such as an ArIcam type device as described in the following Australian provisional patent specifications incorporated here by cross- reference: Australian Filing Date Title Provisional Number P07991 15-Jul-97 Image Processing Method and Apparatus (ARTO1}-WO99/04368 P07988 15-Jul-97 Image Processing Method and Apparatus (ARTO2) -WO99/04368 P07993 15-Jul-97 Image Processing Method and Apparatus (ART03) -W099/04368 P08012 15-Jul-97 Image Processing Method and Apparatus (ARTO5) -WO99/04368 P08017 15-Jul-97 Image Processing Method and Apprau. (ARTO6) -W099/04368 P08014 15-Jul-97 Media Device (ARTO7) -W99/04368 P08025 15-Jul-97 Image Processing Method and Apparatus (ART08) -WO99/04368 P08032 15-Jul-97 Image Processing Method and Apparatus (ARTO9) -WO99/04368 P07999 15-Jul-97 Image Processing Method and Apparatus (ARTIO) -W099/t4368 PO7998 15-Jul-97 Image Processing Method and Apparatus (ARTI I1) -W099/04368 P08031 15-Jul-97 Image Processing Method and Apparatus (ART12) -WO99/04368 P08030 15-Jul-97 Media Device (ART13) -WO99/04368 P07997 15-Jul-97 Media Device (ARTIS) -WO99/04368 P07979 15-Jul-97 Media Device (ARTI6) -WO99/04368 P08015 15-Jul-97 Media Device (ARTI7) -WO99/04368 P07978 15-Jul-97 Media Device (ARTIS) -UJSSN 09/113,067 P07982 15-Jul-97 Data Processing Method and Apparatus (ARTI9) -WO99/04368 P07989 15-Jul-97 Data Processing Method and Apparatus (ART20) -WO99/04368 19 15-Jul-97 Media Processing Method and Apparatus (ART2 1) -WO99/04368 P07980 15-Jul-97 Image Processing Method and Apparatus (ART22) -W99/04368 P07942 15-Jul-97 Image Processing Method and Apparatus (ARl3) -W099/04368 PO8018 15-Jul-97 Image Processing Method and Apparatus (ART24) -WO99/i04368 P07938 15-Jul-97 Image Processing Method and Apparatus (ART25) -W09Y9/04368 P08016 15-Jul-97 Image Processing Method and Apparatus (ART26) -WO9904368 P8024 15-Jul-97 Image Processing Method and Apparatus (ART27) -WO9904368 P07940 15-Jul-97 Data Processing Method and Apparatus (ART28) -WO99/04368 P07939 15-Jul-97 Data Processing Method and Apparatus (ART29) -WO99/04368 PO8501 1 I -Aug-97 Image Processing Method and Apparatus (ART30)-1US 6,137,500 PO8500 11-Aug-97 Image Processing Method and Apparatus (ART31) L'SSNO9i 12,796 P07987 15-Jul-97 Data Processing Method and Apparatus (ART32) -WO99/04368 P08022 15-Jul-97 Image Processing Method and Apparatus (ART33) -W099/04368 26 P08497 11-Aug-97 Image Processing Method and Apparatus (ART30) -US 6,137,500 P08029 15-Jul-97 Sensor Creation Method and Apparatus (ART36) -WO99/04368 P07985 iS-Jul-97 Data Processing Method and Apparatus (ART37) -WO99/04368 P08020 15-Jul-97 Data Processing Method and Apparatus (ART38) -WO99/04368 P08023 15-Jul-97 Data Processing Method and Apparatus (ART39) -WO99/04368 P09395 123-Sep-97 Data Processing Metho ad Apparatus (ART4)-US 6,322,181 P08021 15-Jul-97 Data Processing Method and Apparatus (ART40) -WO99/04368 P08504 I1-Aug-97 Image Prcessing Method and Apparatus (ART42)-USSN 09/112,786 P8000 15-Jul-97 Data Processing Method and Apparatus (ART43) -WO99/04368 P07977 15-Jul-97 Data Processing Method and Apparatus (ART44}-USSN 09/112,782 P07934 15-Jul-97 Data Processing Method and Apparatus (ART45)-USSN 09/113,056 P07990 15-Jul-97 Data Processing Method and Apparatus (ART46) -USSN 09/113,059 P08499 I1-Aug-97 Image Processing Method and Apparatus (ART47) -USSN 09113,091 P08502 11-Aug-97 image Processing Method and Apparatus(ART48)-US 6,381,361 P07981 15-Jul-97 Data Processing Method and Apparatus (ART50)-US 6,317,192 PO7986 15-Jul-97 Data Processing Method and Apparatus(ARTS 1)-USSN 09/113,057 P07983 15-Jul-97 Data Procetssing Method and Apparatus (ART52) -USSN 09/113,054 P08026 15-Jul-97 Image Processing Method and Appamtus (ART53)-USSN 09/112,752 P08027 15-Jul-97 Image Processing Method and Apparatus (ART54-USSN 09/112,759 P08028 15-Jul-97 Image Processing Method and Apparatus (ART56)-USSN 09/112,757 PO9394 23-Sep-97 Image Processing Method and Apparatus (ART57) )-US 6,357,135 P09396 23-Sep-97 Data Processing Method and Apparatus (ART58)-USSN 09/113,107 P09397 23-Sep-97 Data Processing Method and Apparatus (ART59) -WO99/0368 1 P09398 23-Sep-97 Data Processing Method and Apparatus (ART6$-US 6,353,772 P9399 23-Sep-97 Data Processing Method and Apparatus (ART6 1)-US 6,106,147 P09400 23-Sep-97 Data Processing Method and Apparatus (ART62)-USSN 09/112,790 P09401 23-Sep-97 Data Processing Methiod and Apparatus (ART63)-US 6,304,291 PO9402 23-Sep-97 Data Processing Metiod ad Apparatus (ART64) -USSN 09/112,788 P09403 23-Sep-97 Data Proccsing Method and Apparatus (ART65)-tUS 6,305,770 P09405 23-Sep-97 Data Processing Method and Apparatus (ART66)-US 6,289,262 PP0959 16-Dec-97 A Data Processing Method and Apparatus (ART68) -US 6,315,200 PP1397 19-Jan-98 A Media Device (ART69)US 6,217,165 It would be appreciated by a person skilled in the art that numerous variations and'or modifications may be made to the present invention as shown in the specific embodiment wvithout departing from the spirit or scope of the invention as broadly described. The present embodiment is, therefore, to be considered in all respects to be illustrative and not restrictive. -27 Tables of Drop-on-Demand Inkjets Eleven important characteristics of the fundamental operation of individual inkjet nozzles have been identified These characteristics are largely orthogonal, and so can be elucidated as an eleven dimensional matrix, Most of the eleven axes of this matrix include entries developed by the present assignee. The following tables form the axes of an eleven dimensional table of inkjet types. Actuator mechanism (18 types) Basic operation mode (7 types) Auxiliary mechanism (8 types) Actuator amplification or modification method (17 types) Actuator motion (19 types) Nozzle refill method (4 types) Method of restricting back-flow through inlet (10 types) Nozzle clearing method (9 types) Nozzle plate constructonn (9 types) Drop ejection direction (5 types) Ink type (7 types) The complete eleven dimensional table represented by these axes contains 36.9 billion possible configurations of inkjet nozzle. While not all of the possible combinations result in a viable inkjet technology, many million configurations are vable. It is clearly impractical to elucdate all of the possible configurations. Instead, certain inkjet types have been investigated in detail. These are designated 1J01 to IJ45 above. Other inkjet configurations can readily be derived from these 45 examples by substituting alternative configurations along one or more of the 11 axes. Most of the 1301 to 1345 examples can be made into inkjet print heads with characteristics superior to any currently available inkjet technology, Where there are prior art examples known to the inventor, one or more of these examples ar listed in the examples column of the tables below. The 1101 to L45 series are also listed in the examples couinn. In some cases, a printer may be listed more than once in a table, where it shares characteristics with more than one entry Suitable applications include: Home printers, Office network printers, Short run digital printers, Commercial print systems, Fabric print Pprint, P rinters, Internet WWW printers, Video printers, Medical imaging, Wide format printers, Notebook PC printers, Fax machines, Industrial printing systems, Photocopiers, Photographic minirabs etc The information associated with the aforementioned i dimensional matrix are set out in the following tables. Actuator mechanism (applied only to selected ink drops) __1111111 Actuator Mechanism Thermal bubble Description An electrothermal heater heats the ink to above boiling point, transferring significant heat to the aqueous ink. A bubble nucleates and quickly forms, expelling the ink. The efficiency of the process is low, with typically less than 0.05% of the elecrical energy being transformed into kinetic energy of the drop. Advantages Large force generated Simple construction No moving parts Fast operation Small chip area requiahd for actuator SDisadvantages Diavaae Piezoelectric Electro-strictive A piezoelectric crystal such as lead lanthanum zirconate (PZT) is electrically activated, and either expands, shears, or bends to apply pressure o the ink, ejecting drops. Low power consumption Many ink types can be used Fast operation High efficiency I High power Iik carrier limited to water Low efficiency High temperatures required High mechaical stress Unusual materials required Large drive transistors Cavitation causes actuator failure Kogation reduces bubble formation Large print heads are difficult to fabricate Very large area required for actuator Difficult to integrate with electronics High voltage drive transistors required Full pagewidth print heads impractical due to actuator size Requires electrical poling in high field strengths during nanufacture Low maximum strain (approx. 0.01%) Large area tequired for actuator due to low strain Response speed is marginal 10 ps) High voltage drive transistors required Full pagewidth print heads impractical due to actuator size Examples Canon Bubbiejet 1979 Endo et al GB patent 2,007,162 Xerox heater-in-pit 1990 Hawkins et al USP 4,899,181 Hewlett-Packard TIJ 1982 Vaught et al USP 4,490,728 Kyser et at USP 3,946,398 Zoltan USP 3,683,212 1973 Stemme USP 3,747,120 Epson Stylus Tektronix IJ04 Seiko Epson, Usui et all JP 253401/96 IJ04 An electric field is used to activate electrostriction in relaxor rnaerials such as lead lanthanum zirconate titanate (PLZT) or lead magnesium niobate (PMN). Low power consumption Many ink types can be used Low thermal expansion Electric field strength required (approx. V/n) can be generated without difficulty Does not require electrical pling I i -II 11~ ~11~1111~11~ Ferroelectric Electrostatic plates An electric field is used to induce a phase transition between the antifeTroelecric (AFE) and ferroelectric (FE) phase. Perovskite materials such as tin modified lead lanthanum zirconate titanate (PIISnT) exhibit large strains of up to 1% associated with the AFE to FE phase transition. Low power consumption Many ink types can be used Fast operation I is) Relatively high longitudinal strain High efficiency Electric field strength of around 3 V/tpm can be readily provided Low power consumption Many ink types can be used Fast operation Difficult to integrate with electronics Unusual materials such as PLZSnT are required Actuators require a large area Conductive plates are separated by a compressible or fluid dielectric (usually air). Upon application of a voltage, the plates attract each other and displace ink, causing drop ejection. The conductive plates may be in a comb or honeycomb structure, or stacked to increase the surface area and therefore the force. A strong electric field is applied to the ink, whereupon electrostatic attraction accelerates the ink towards the print medium. Difficult to operate electrostatic devices in an aqueous environment The electrostatic actuator will normally need to be separated from the ink Very large area required to achieve high forces High voltage drive transistors may be required Full pagewidth print heads are not competitive due to actuator size 1302, 104 Electrostatic pull on ink Low current consumption Low temperature High voltage required May be damaged by sparks due to air breakdown Required field strength increases as the drop size decreases High voltage drive transistors required Eectrostatic field attracts dust 1989 Saito et al, USP 4,799,068 1989 Miura et a, USP 4,810,954 Tone-jet I f 1~__~111111_1---1111 ___111111 I I Permanent magnet electro-magnetic An electromagnet directly attracts a permanent magnet, displacing ink and causing drop ejection. Rare earth magnets with a field strength around 1 Tesla can be used. Exanples are: Samarium Cobalt (SaCo) and magnetic materials in the neodymium iron boron family (NdFeB, NdDyFeBNb, NdDyFcB, Cec) Low owwer consumption Many ink types can be used Fast operation High efficiency Easy extension from single nozzles to pagewidth print heads r Complex fabrication Permanent magnetic material such as Neodymium iron Boron (NdFeB) required. High local currents required Copper metalization should be used for long electromrigration lifetime and low resistivity Pigmented inks are usually infeasible Operating temperature limited to the Curie temperature (around 540 K) 1,107, 111O 1111 Soft magnetic core electro-magnetic A solenoid induced a magnetic field in a soft magnetic core or yoke fabricated from a fnrouis material such as electroplated iron alloys such as CoNiFe CoFe, or NiFe alloys Typically, the soft magnetic material is in two parts, which are normally held apart by a spring. When the solenoid is actuated, the two parts attract, displacing the ink. The Lorenz force acting on a curent carrying wire in a magnetic field is utilized. This allows the magnetic field to be supplied externally to the print head, for example with rare earth permanent magnets. Only the current carrying wire need be fabricated on the print-hed, simplifying materials requirements. Low power consumption Many ink types can be used Fast operation High efficiency Easy extension from single nozzles to pagewidth print heads Complex fabrication Materials not usually present in a CMOS fab such as NiFe, CoNiFe, or CoFe are required High local currents required Copper imetalization should be used for long electromigration lifetime and low resistivity Electroplating is required High saturation flux density is required (2.0-2.1 T is achievable with CoNiFe Force acts as a twisting motion Typically, only a quarter of the solenoid length provides force in a useful direction High local currents required Copper metalization should be used for long electromigration liftime and low resistivity Pigmented inks are usually infeasible D01, IJ05, 1l08, IJO IJ12, 114, U 15, 117 IJ06, lJ 1, IJ 3,J 6 Magnetic Lorenz force Low power consumption Many ink types can be used Fast operation High efficiency Easy extension from single nozzles to pagewidth print heads i -~~~~~~1111~---~1111Illll~ ~YIIIIIII- Magneto-striction Surface tension reduction The actuator uses the giant magneostrictive effect of materials such as Terfenol-D (an alloy ofterbium, dysprosium and iron developed at the Naval Ordnance Laboratory, hence Ter-Fe- NOL). For best efficiency, the actuator should be pro-stressed to approx. 8 MPa. Ink under positive pressure is held in a nozzle by surface tension. The surface tension of the ink is reduced below the bubble threshold, causing the ink to egress fromn the nozle. The ink viscosity is Ically reduced to select which drops are to be ejeted. A viscosity reduction n a be achieved electrothermally with most inks, but special inks can be engineered for a 100:1 viscosity reduction. An acoustic wave is generated and focussed upon the drop ejection region. Many ink types can be used Fast operation Easy extension from single nozzles to pagewidth print heads High force is available Low power consumption Simple construction No unusual materials required in fabrication High efficiency Easy extension from single nozzles to pagewidth print heads Simple construction No unusual materials required in fabrication Easy extension from single nozzles to pagewidth print heads Force acts as a twisting motion Unusual materials such as Terfenol-D are required High local currents required Copper metaization should be used for long electromigration lifetime and low resistivity Pre-stressing may be required Requires supplementary force to effect drop separation Requires special ink surfactants Speed may be limited by surfactant properties Requires supplementary force to effect drop separation Requires special ink viscosity properties High speed is difficult to achieve Requires oscillating ink pressure A high temperature difference (typically 80 degrees) is required Fischenbeck, USP 4,032,929 1I25 Silvesbrook, EP 0771 658 A2 and related patent applications Viscosity reduction Silverbrook, EP 0771 658 A2 and related patent applications Acoustic Can operate without a nozzle plate Complex drive circuitry Complex fabrication Low efficiency Poor control of drop position Poor control of drop volume 1993 Hadimioglu et at, EUP 550,192 1993 Elrod et al, EUP 572220 1 111 11 32 Thermoelastic bend actuator High CTE thermoelastic actuator An actuator which relies upon differential thermal expansion upon Joule heating is used. A material with a very high coefficient of thernal expansion (CTE) such as polytetrafluoroethylene (PTFE) is used. As high CTE materials are usually non-conductive, a heater fabricated from a conductive material is incorporated. A 50 pm long PTFE bend actuator with polysilicon heater and 15 rnW power input can provide 180 iN force and 10 l.m deflection. Actuator motions include: Bend Push Buckle Rotate Low power consumption Many ink types can be used Simple planar fabrication Small chip area required for each actuator Fast operation High efficiency CMOS compatible voltages and currents Standard MEMS processes can be used Easy extension from single nozzles to pagewidth print heads High force can be generated PTFE is a candidate for low dielectric constant insulation in ULSI Very low power consumption Many ink types can be used Simple planar fabrication Small chip area required for each actuator Fast operation High efficiency CMOS compatible voltages and currents Easy extension from single nozzles to pagewidth print heads Efficient aqueous operation requires a thermal insulator on the het side Corrosion prevention can be difficult Pigmented inks may be infeasible, as pigment particles may jam the bend actuator 1103, 1109, 1317, 1118 U19, IJ20, U21, 1122 U23, 1124, 27, U28 U29, [130, IJ31, 132 1J33, 134, 1335, 1136 IJ37, 1138 ,I39, 1140 1U41 Requires special material PTFE) Requires a PTFE deposition prcess, which is not yet standard in ULSI fabs PTFE deposition cannot be followed with high tempeature (above 350 processing Pigmented inks may be infeasible, as pigment paricles may jam the bend actuator 109, 1117, i 18, 121, IJ22, 123, IJ24 U27, U28, 1129, 1330 1J31, 1142, I43, IJ44 I.r 111 1 Conductive polymer thermoelastic actuator A polymer with a high coefficient of thermal expansion (sudc as PTFE) is doped with conducting substances to increase its conductivity to about 3 orders of magnitude below that of acpper. The conducting polymer expands when resistively heated. Examples of conducting dopants include: Carbon nanotubes Metal fibers Conductive polymers such as doped polythiophene Carbon granules A shape memory alloy such as TiNi (aiso known as Nitinol Nickel Titanium alloy developed at the Naval Ordnance Laboratory) is thermally switched between its weak martensitic state and its high stiftiess austenic state. The shape of the actuator in its martensitic state is deformed relativc to the austenic shape. The shape change causes ejection of a drop. High force can be generated Very low power consumption Many ink types can be used Simple planar fabrication Small chip area required for each actuator Fast operation High efficiency CMOS compatible voltages and currents Easy extension from single nozzles to pagewidth print heads Shape memory alloy High force is available (stresses of hundreds of MPa) Large strain is available (more than 3%) High corrosion resistance Simple construction Easy extension from single nozzles to pagewidth print heads Low voltage operation Linear Magnetic actuators can be constructed with high thrust, long ravel, and high efficiency using planar seniconductor fabrication techniques Long actuator travel is available Medium force is available Low voltage operation Requires special materials development (High CTE conductive polymer) Requires a PTFE deposition process, which is not yet standard in ULSI fabs PTFE deposition cannot be followed with high temperature (above 350 0 C) processing Evaporation and CVD deposition techniques cannot be used Pigmented inks may be infeasible, as pigment particles may jam the bend actuator Fatigue limits maximum number of cycles Low strain is required to extend fatigue resistance Cycle rate limited by heat removal Requires unusual materials (TiNi) 'The latent heat oftransformation must be provided High current operation Requires pre-stressing to distort the martensitic state Requires unusual semiconductor materials such as soft magnetic alloys CoNiFe Some varieties also require permanent magnetic materials such as Neodymium iron boron (NdFeB) Requires complex multi-phase drive circuitry High current operation Linear Magnetic Actuator Basic operation mode Linear magnetic actuators include the Linear Induction Actuator (LIA), Linear Penmanent Magnet Synchronous Actuator (LPMSA), Linear Reluctance Synchronous Actuator (LRSA), Linear Switched Reluctance Actuator (LSRA), and the Linear Stepper Actuator (LSA). i I tXmul.'. cx-_ I uspoanuaaiJ mnioue Actuator directly pushes ink This is the simplest mode of operation: the actuator directly supplies sufficient kinetic energy to expel the drop. The drop must have a sufficient velocity to overcome the surface tension. Advantages Simple operation No external fields required Satellite drops can be avoided ifdrop velkcity is less than 4 mrs Can be efficient, depending upon the actuator used Disadvantages Drop repettion rate is usually limited to less than 10 KHz. However, this is not fundamental to the method, but is related to the refill method normally used All of the drop kinetic energy must be provided by the actuator Satellite drops usually form if drop velocity is greater than 4.5 m/s Examples Thermal inkjet Piezoelectric inkjet 1301, 102, IJ03,104 J05, 1306, 3U07, 1109 l111, IU12,1314, 116 1J20, IJ22, UJ23, 1124 IJ25, IJ26, 1U27, 128 1329, IJ30, IU31, I32 1333, 1134, 1135, 1J36 1137, 1J38, 1339, J140 1141, 1U42, U43, 1I44 Proximity Elctrostatic pull ona ink Magnetic pull on ink The drops to be printed are selected by some Very s manner thermally induced surface tension be use reduction of pressurized ink), Selected drops The dn are separated from the ink in the nozzle by need t contact with the print medium or a transfer separa roller, 'Hne drops to be printed are selected by some Very si manner thromally induced surface tension be use reduction of pressuried ink). Selected drops The dn are separated from the ink in the nozzle by a need to strong electric field. separat I i imple print head fabrication can op selection means does not provide the energy required to te the drop from the nozzle imple print head fabrication can op selection means does not Sprovide the energy required to Ste drop from the nozzle Requires close proximity between the print head and the print media or transfer roller May require two print heads printing alternate rows of the image Monolithic color print heads are difficult Requires very high electrostatic field Electrostatic field for small nozzle sizes is above air breakdown Electrostatic field may attract dust Requires magnetic ink Ink colors other tfan black are difficult Requires very high magnetic fields Silverbrook, EP 0771 658 A2 and related patent applications Silverbrook, EP 0771 658 A2 and related patent applications Torne-Jet Silverbrook, EP 0771 658 A2 and related patent applications The drops to be printed are selected by some manner thernally induced surface tension reduction ofpressurized ink). Selected drops are separated from the ink in the nozzle by a strong magnetic field acting on the magnetic ink Very simple print head fabrication can be used The drop selection means does not need to provide the energy required to separate the drop from the nozzle R3- .4 1R30-AUr Shutter Shuttered grili The actuator moves a shutter to block ink flow to the nozzle The ink pressure is pulsed at a multiple of the drop ejection frequency. The actuator moves a shutter to block ink flow through a grill to the nozzle. The shutter movement need only be equal to the width of the grill holes. A pulsed magnetic field attrats an 'ink pusher' at the drop ejection frequency. An actuator controls a catch, which prevents the ink pusher from moving when a drop is not to be ejected. High speed (>50 KHz) operation can be achieved due to reduced refill time Drop timing can be very accurate The actuator energy can be very low Actuators with small travel can be used Actuators with small force can be used High speed (>50 KCHz) operation can be achieved Extremely low energy operation is possible No heat dissipation problems Moving parts are reuired Requires ink pressure modulator Friction and wear must be considered Stiction is possible T 113, 5 7, 62-1 i Moving pans are required Requires ink pressure modulator Friction and wear must be considered Stiction is possible Requires an external pulsed magnetic field Requires special materials for both the actuator and the ink pusher Complex construction IJ08, 5lS, J118, I19 Pulsed magnetic pull on ink pusher I Auxiliary mechanism (applied to all nozzles) i Auxiliary mechanism (applied to all nozzles) Auxiliary Mechanism None Oscillating ink pressure (including acoustic stimulation) Description Advantages Disadvantages The actuator directly fires the ink drop, and there is no external field or other mechanism requiyed. The ink pressure oscillates, providing much of the drop ejection energy. The actuator selects which drops are to be fired by selectively blocking or enabling nozzles. The ink pressure oscillation may be achieved by vibrating the print head, or preferably by an actuator in the ink supply. Simplicity of constrction Simplicity of operation Small physical size Drop ejection energy must be supplied by individual nozzle actuator Examples Most inkjets, including piezoelectric and thermal bubble. IJO1- U07, 1109, 1 11 J112, 1114, 120, IJ22

1123-145 Silverbrook, EP 0771 658 A2 and related patent applications 1J08, I313, 1J15, 117 Jl18, I19, 1121 Oscillating ink pressure can provid refill pulse, allowing higher operat speed The actuators may operate with m lower energy Acoustic lenses can be used to foe the sound on the nozzes e a Requires external ink pressure oscillator ing Ink pressure phase and amplitude must be carefully controied uch Acoustic reflections in the ink chamber must be designed for us 1 1 n unn N Media proximity Transfer roller Electrostatic Direct magnetic fiedd The print head is placed in close proxinity to the print medium. Selected drops protrude from the print head irther than unselected drops, and contact hie print medium. The drop soaks into the medium fast enough to cause drop separation. Drops arc printed to a transfer iroler instead of straight to the print medium. A transfer roller can also be used for proximity drop separation. An electric field is used to accelerate selected drops towards the print medium. Low power High accuracy Simple print head construction Precision assembly required Paper fibes may cause problems Cannot print on rough substrates High accuracy Bulky Ik Wide range of print substrates can be used Ink can be dried on the transfer roller Low power Simple print head construction Low power Simple print head construction Expensive Complex construction Field strength required for separation of small drops is near or above air breakdown Silverbrook, EP 0771 658 A2 and related patent applications Silverbrook, EP 0771 658 A2 and related patent applications Tektronix hot melt piezoelectric inkjet Any of the iJ series Silvabrook, EP 0771 658 A2 and related patent applications Tone-Jet Silverbrook, EP 0771658 A2 and related patent applications A magnetic field is used to accelerate selected drops of magnetic ink towards the print medium. Cross magnetic field Pulsed magnetic field The print head is placed in a constawn magnetic fieldi The Lorenz force in a current carrying wire is used to move the actuator. A pulsed magnetic field is used to cyclically attract a paddle, which pushes on the ink. A small actuator moves a catch, which selectively prevents the paddle from moving. Does not require magnetic materials to be integrated in the print head manufacturing process Requires magnetic ink Requires strong magnetic field Requires external magnet Current densities may be high, resulting in electromigration problems Complex print head construction Magnetic materials required in print head It06, U16 1310 Very low power operation is possible Small print head size Actuator amplification or modification method Actuator amplification Description Advantages Disadvanages Examples None No actuator mechanical amplification is used Operational simplicity Many actuator mechanisms have insufficient trawve, fIhenal Bubble Inkjet The actuator directly drives the drop ejection or insufficient force, to efficiently drive the drop 10J1, 1302, U06, U07 process. i ejection process 1 16, 125, 1126 il'~ Differenatial expansion bend actuator Transient bend actuator i -i An actuator material expands more on one side than on the other. The expansion may be thenral, piezoelectric, magnetostrictive, or other mechanism. A trilayer bend.actuator where e e two outside layers are identical This cancels bend due to ambient temperature and residual stress. The actuator only responds to transient heating of one side or the other. A series of thin actuators are stacked. This can be apprpiate where actuators require high electric field strength, such as eectrostatic and piezoelectric actuators. Actuator stack Multiple actuators Linear Spring Reverse spring Provides greater travel in a reduced print head area The bend actuator converts high force low travel actuator mechanism to high travel, lower force mechanism. Very good temperature stability High speed, as a new drop can be fired before heat dissipates Cancels residual stress of formation Increased travel Reduced drive voltage Increases the force available from an actuator Multiple actuators can be positioned to control ink flow accurately Matches low ravel actuator with higher travel requirements Non-contact method of motion transformation Better coupling to the ink High stresses are involved Care must be taken that the materials do not delaminate Residual bend resulting from high temperature or high stress during formation High stesses are involved Care must be taken that the materials do not delaminate 1103, 109, I117-IJ24 1127, 1129-J39, J142, 1343, U44 -J40, 4 Increased fabrication complexity Increased possibility of short circuits due to pinholes Some piezoelectric ink jets IJ04 Multiple smaller actuators are used Ssimultaneously to move the ink. Each actuator need provide only a portion of the force required. A linear spring is used to ransform a motion with small tavel and high force into a longer travel, lower force motion. The actuator loads a spring. When the actuator is tumed of, the spring releases. This can reverse the force/distance curve of the actuator to make it compatible with the force'time requirements of the drop ejection. Actuator forces may not add linearly, reduc efficiency Requires print head area for the spring Fabrication complexity High stress in the spring ing 1312, 1113, 3J18, 120 IJ22, 1J28, 1342, IJ43 -1 IJo5, 1i 1 Coiled actuator Flexure bend actuator Gears Catch i A bend actuator is coiled to provide greater travel in a reduced chip area A bend actator has a small region near ihe fixture point, which flexes much more readily than the rmnainder of the actuator. The actuator flexing is effectively converted from an even coiling to an angular bend, resulting in greater travel of the actuator tip. Gears can be used to increase travel at the expense of duration. Circular gears, rack and pinion, ratchets, and other gearing methods can be used. The actuator controls a small catch. The catch either enables or disables movement of an ink pusher that is controlled in a bulk manner. Incrases travel Reduces chip area Planar implementations are relatively easy to fabricate. Generally restricted to planar implementations due to extreme fabrication difficulty in othe orientations. 1117, 1U21, U34, 1J35 I Simple means of increasing travel of a bend actuator Care must be taken not to exceed the elastic limit in the flexure area Stress distribution is very uneven Difficult to accurately model with finite element analysis J11, 1119, 1J33 Low force, low travel actuators can be used Can be fabricated using standard surface MEMS processes Very low actuator energy Very small actuator size i I Moving parts are required Several actuator cycles are required More complex drive electronics Complex construction Friction, friction, and wear are possible Complex construction Requires external force Unsuitable for pigmented inks Buckle plate A buckle plate can be used to change a slow actuator into a fast motion. t can also convert a high force, low travel actuator into a high travel, medium force motion. A tapered magnetic pole can increase travel at the expense of force. SVery fast movement achievable Must stay within elastic limits of the materials for long device life High stresses involved Generally high power requirement S Hirata et al, "An Ink-jet Head Proc. IEEE MEMS, Feb. 1996, pp418-423. U118, IJ27 Ti14 i i Tapered magnetic pole i I Linearizes the magnetic force/distance curve Complex construction A lever and fulcrum is used to transform a motion with small travel and high force into a motion with longer travel and lower force. The lever can also reverse the direction of travel. I Matches low travel actuator with higher travel requirements Fulcuram area has no linear movement, and can be used for a fluid seal -r High stress around the futcmrum 1132, 136, 1J37 !I 1~~1111111--- I 1 Rotary impeller The actuator is connected to a rotary impeller. A small angular deflection of the actuator results in a rotation of the impeller vanes, which push the ink against stationary vanes and out of the nozzle High mechanical advantage The ratio of force to travel of the actuator can be matched to the nozzle requirements by varying the number of impeller vanes No moving parns Complex construction Unsuitable for pigmented inks Large area required Only relevant for acoustic ink jets Acoustic lens A refractive or diffactive zone plate) acoustic lens is used to concentrate sound waves. A sharp point is used to concentrate an electrostatic field. 1993 Hadimiogii et al, EUP 550,192 1993 Elrod et ai, EUP 572,220 Tone-jet Sharp conductive point Simple construction Difficult to fabricate using standard VLSI processes for a surface ejecting ink-jet Only relevant for electrostatic ink jets Actuator motion Actuator motion Volume expansion Linear, normal to chip surface Linear, parallel to chip surface Membrane push Lsescnpnton The volume of the actuator changes, pushing the ink in all directions, The actuator moves in a direction normal to the print head surface. The nozzle is typically in the line of movement. The actuator moves parallel to the print head surface. Drop ejection may still be nonmai to the surface. An actuator with a high force but small area is used to push a stiff membrane that is in contact with the ink. Advantages Simple construction in the case of thermal ink jet Efficient coupling to ink drops ejected normal to the surface Disadvantages High energy is typically required to achieve volume expansion. This leads to thermal stress, cavitation, and kogation in thermal inkjet implementations High fabrication complexity may be required to achieve perpendicular motion Fabrication complexity Friction Stiction Examples Hewlett-Packard Thermal Inkjet Canon Bubblejet 1JOi, 102, 1304, J1107 Il 1,1114 1112, 1113, 15, 1J33, 134, 1335, 1336 Suitable for planar fabrication The effective area of the actuator becomes the membrane area t Fabrication complexity Actuator size Difficulty of integration in a VLSI process Device complexity May have friction at a pivot point 1982 Howkins USP 4,459,601 J05, 108, Il3, 128 I Rotary The actuator causes the rotation of some element, such a grill or impeller Rotary levers may be used to ircrase travel Small chip area requirements ~IIIIIll~-i----~lll~ll~__ll1111111~a~--- i ~I i 11 Bend Swivel Straighten Double bend The actuator bends when energized. This may be due to differential thenal expansion, piezoelectric expansion, magnetostricion, or other form of relative dimensional change. A very small change in dimensions carl be converted to a large motion. Requires the actuator to be made from at least two distinct layers, or to have a thermal difference across the actuator Inefficient coupling to the ink motion 1970 Kyser et a USP 3,946,398 1973 Stemme USP 3,747,120 1103, 1J09, IJ1O, 1 19 123, 1324, 125, 1129 1130, IJ31, 133, J34 1135 i 06 Shear Radial constriction Coil I utncoil Bow Push-Pull The actuator swivels around a central pivot. This motion is suitable where there are opposite forces applied to opposite sides of the paddle, e.g. Lorenz force The actuator is normally bent, and straightens when energized. The actuator bends in one direction when one element is energized, and bends the other way when another element is energized. Energizing the actuator causes a shear motion in the actuator matcrial. The actuator squeezes an ink reservoir, forcing ink from a consricted nozzle. A coiled actuator uncoils or coils more tightly. Ihe motion of the free end of the actuator ejects the ink. The actuator bows (or buckles) in the middle when energized Two actuators control a shutter. One actuator pulls the shutter, and the other pushes it. I Can be used with shape memory alloys wher e e austenic phase is planar One actuator can be used to power two nozzles. Reduced chip size. Not sensitive to ambient temperature r- Requires careful balance of stresses to ensure that the quiescent bend is accurate Difficult to make the drops ejected by both bend directions identical. A small efficiency loss compared to equivalent single bend actuators. 1126, IJ32 J36, 1137, 338 i I Allows operation where the net linear force on the paddle is zero Small chip area requirements Can incenase the effective travel of piezoelcrric actuators Relatively easy to fabricate single norzzls from glass tubing as macroscopic structures Not readily applicable to other actuator mechanisms High fore required Inefficient Difficult to integrate with VLSI processes S1985 Fishbeck USP 4,584,590 1970 Zoltan USP 3,683,212 Easy to fabricate as a planar VLSI process Small area required, therefore low cost Can increase the speed of travel Mechanically rigid 4 I-~~IIIIII11111111 Difficult to fabricate for non-planar devices Poor out-of-plane stiffness Maximum travel is constrained High force required i17, 1121, 1134, 1J35 1J16, IlS8, J127 ,118 111111~11 The structure is pinned at both ends, so has a high out-of-plane rigidity Not readily suitable for inkjets which directly push the ink 511CRR Curt inwards Curl outwards is Acoustic vibration r A set of actuators curl inwards to reduce the Good fl volume of ink that they enclose. the actu A set of actuators curl outwards, pressurizing Relativ ink in a chanber surrounding the acuators, and expelling ink from a nozzle in the chamber Multiple vanes enclose a volume of ink. These High ef simultaneously rotate, reducing the volume Small d between the vanes. The actuator vibrates at a high frequncy. The acy from th uid flow to the region behind ator increases efficiency ely simple construction iciency hip area uator can be physically distant e ink i_ Design complexity J20, 1342 Relatively large chip area U143 High fabrication complexity Not suitable for pigmented inks Large area required for efficient operation at useful frequencies Acoustic coupling and crosstalk Complex drive circuitry Poor control of drop volume and position Various other tradeoffs are required to eliminate moving parts 1722 1993 Hadimioglu a al, EUP 550,192 1993 Elrod e al, EUP 572,220 Silverbrook, EP 077 1658 A2 and related patent applications Tone-jet q None In various inkjet designs the actuator does not move. No moving parts Nozzle refill method I_ Nozze refill method Description Advantages Disadvantages Exampes Surface tension After the actuator is energized, it typically returns rapidly to its normal position This rapid return sucks in air through the nozzle opening. The ink surface tension at the nozzle then exerts a small force rstoring the meniscus to a minimum area. Ink to the nozzle chamber is provided at a pressure that oscillates at twice the drop ejection frequency. When a drop is to be ejected, the shutter is opened for 3 half cycles: drop ejection, actuator reurn, and refill. Fabrication simplicity Operational simplicity Low speed Surface tension force relatively small compared to actuator force Long refill time usually dominates the total repetition rate Requires common ink pressure oscillator May not be suitable for pigmented inks Thermal inkjet Piezoelectric inkjet 130 -107, iJl0-iJ14 1316, 1320, 1122-1145 Shuttered oscillating ink pressure High speed Low actuator energy, as the actuator need only open or close the shutter, instead of ejecting the ink drop 108,1113, IJ15, IJ17 J118, U39, 1J21 1 L 1R3-U 111111 Refill actuator Positive ink pressure After the main actuator has ejected a drop a second (refill) actuator is energized The refill actuator pushes ink into the nozzle chamber. 'IThe refill actuator returns slowly, to prevent its return from mptying the chamber again. The ink is held a slight positive pressure After the ink drop is ejected, the nozzle chamber fills quickly as surface tension and ink pressure both operate to refill the nozzle. High speed, as the nozle is actively refilled High refill rate, therefore a high drop repetition rate is possible ~a 1 1 Requires two independent actuators per nozzle Surface spill must be prevented Highly hydrophobic print head surfaces are required 1309 Silvebrook, EP 0771 658 A2 and related patent applications Alternative for: 001-007, 1J0l-J14 1J16, 1120, 1J22-IJ45 Method of restricting back-flow through inlet ie riacK-now restricion method ecnipnton e Long inlet channel The ink inlet channel to the nozzle chamber is made long and relatively narrow, relying on viscous drag to reduce inlet back-flow. Advantages Design simplicity Operational simplicity Reduces crosstalk Disadvantages Examples f Positive ink prssure I The ink is under a positive pressure, so that in the quiscent state some of tdie ink drop alrmdy protrudes from the nozzle. This reduces the pressure in the nozzle chamber which is required to eject a certain volurme of ink. The reduction in chaunber pressure results in a reduction in ink pushed out through the inlet Drop selection and separation forces can be reduced Fast refill time Restricts refill rate Ther May result in a relatively large chip area Piez Only partially eftfitive 1342, Requires a method (such as a nozzle rim or effective Silv hydrophtobizing, or both) to prevent flooding of the and ejection surface of te print hea& Poss follo 1114, IJ23- IJ44 mal inkjet oelectric inkjet IJ43 rbrook, EP 0771 658 A2 related patent applications ible operation of the wing: 1307, J109- 1l12 U 16, 120, 1122, -1134, UI36- IJ41 I- Baffle Fiexible flap rest inlet One or more baffles are placed in the inlet ink flow. When the actuator is energized, the rapid ink movement creates eddies which restrict the flow through the inlet The slower refill process is unrestricted, and does not result in eddies. rics in this method recently disclosed by Canon, the expanding actuator (bubble) pushes on a flexible flap that resticts the inlet. The refill rate is not as restricted as the long inlet method. Reduces crosstalk Significantly reduces back-flow for edge-shooter thermal inkjet devices Additional advantage of ink filtration ink filter may be fabricated with no additional process steps Inlet filter Small inlet compared to nozzle A filter is located between the ink inlet and the nozzle chamber The filter has a multitude of small holes or slots, restricting ink flow. The filter also removes particles which may block the nozzle. Design complexity May increase fabrication complexity Tektronix hot melt Piezoelectric print heads). Not applicable to most inkjet configurations Increased fabrication complexity Inelastic deformation of polymer flap results in creep over extended use Restricts refill rate May result in complex construction Restrics refill rate May result in a relatively large chip area Only partially effective Requires separate refill actuator and drive circuit Requires careful design to minimize the negative pressure behind the paddle HP Termal Ink let Tektronix piezoelectric inkjet Canon 1304, 112, 1J24, 1327 1329, 1J30 The ink inlet channel to the nozzle chamber has a substantially smaller cross section than that of the nozzle, resulting in easier ink egress out of the nozzle than out of the inlet Design simplicity 1302, U37, I144 ii~l Inlet shutter The inlet is located behind the ink- pushing surface A secondary actuator controls the position of a shutter, closing off the ink inlet when the main actuator is energized. The method avoids the problem of inlet back- flow by arranging the ink-pushing surface of the actuator between the inlet and the nozzle. Increases speed of the ink-jet print head operation Back-flow problem is eliminated 1101, 1103, 1305, 1106 1J07, 1310, 1111, 114 1116, 1122, U123, 1325 Ui28, 1131, U32, I33 1334, 135, 1136, IJ39 1340, IJ41 -4 1 Part of the actuator The actuator and a wall of the ink chamber are Significant reductions in back-flow can Small increase in fabrication complexity J07, 1120, 326, 1138 moves to shut off the arranged so that the motion of the actuator be achieved inlet closes off the inlet. Compact designs possible Nozze actuator does In some configurations of ink jet, there is no Ink back-flow problem is eliminated None related to ink back-flow on actuation Silverrook, EP 0771 658 A2 not result in ink back- expansion or movement of an actuator which and related patent applications flow may cause ink back-flow through the inlet Valve-jet Tone-jet 1108, 13, 11 5, 1J!7 8, I19, 121 Nozze Clearing Method Nozzle Clearing Description Advantages Disadvantages Examples method Normal nozzle firing All of the nozzles are fired perioically, before No added complexity on the print head May not be sufficient to displace dried ink Most inkjet systeris the ink has a chance to dry. When not in use the 1101- I307, U09-J112 nozzles are sealed (capped) against air 1314, J16, 1J21 1122 The nozzle firing is usually perfouned during a

1323- IJ34, IJ36-U45 special clearing cycle, after first moving the print head to a cleaning station. Extra power to ink n systems which hea. the ink, but do not boil it Can be highly effective if the heater is Requires higher drive voltage for clearing Silverbrook, EP 0771 658 A2 heater under normal situations, nozzle clearing can be adjacent to the nozzle May require larger drive transistors and related patentapplications achieved by over-powering the heater and boiling ink at the nozzle. Rapid succession of The actuator is fired in rapid succession. In Does not require extra drive circuits on Effectiveness ds dep substantially upon the May be used with: actuator pulses some configurations, this may cause heat build- the print head configuration of the inkjet nozize 1101 -1307, 1109- I I up at the nozzle which boils the ink, dearing Can be readily controlled and initiated U14, IU16, 1120, 1J22 the nozzle. In other situations, it may cause by digital logic IJ23-125, IJ27-IJ34 sufficient vibrations to dislodge clogged 136-1145 nozzles, a_ I_ I Extra power to ink pushing actuator Acoustic resonance Where an actuator is not normally driven to the limit of its motion, nozzle clearing may be assisted by providing an enhanced drive signal to the actuator. An ultrasonic wave is applial to the ink chamber, This wave is of an appropriate amplitude and frequency to cause sufficient force at the nozzle to clear blockages This is easiest to achieve if the ultrasonic wave is at a resonant frequency of the ink cavity. A microfabricated plate is pushed against the nozzles. The plate has a post for every nozzle. The array of posts The pressure of the ink is temporarily increased so that ink streams from all of the nzzles. This may be used in conjunction with actuator energizing. A flexible 'blade' is wiped across the print head surface. The blade is usually fabricated from a flexible polymer, e.g. rubber or synthetic elastomer. i A simple solution where applicable A high nozzle clearing capability can be achieved May be implemented at very low cost in systems which already include acoustic actuators High implementation cost if system does not ahlrady include an acoustic actuator Not suitable where there is a hard limit to actuator movement May be used with; [J03, IJ09, I16, IJ23, J24, U25, IJ27 1U29,1330, 1131, 132 339, IJ40, J41, IJ42 J143, 144, 1345 U08, 1113, 1315, 1317 1318, 1119, 121 Silverbrook, EP 0771 658 A2 and related patent applications Nozzle clearing plate Ink pressure pulse Print head wiper SCan clear severely clogged nozzles Accurate mechanical alignment is required Moving parts are required There is risk of damage to the nozzles Accurate fabrication is required May be effective where other methods cannot be used Effective for planar print head surfaces Low cost I Requires pressure pump or other pressure actuator Expensive Wasteful of ink May be used with all U series ink jets Many inkjet systems Difficult to use if print head surface is non-planar or very fragile Requires mechanical parts Blade can wear out in high volume print systems L. Separate ink boiling A separate heater is provided at the nozzle Can be effective where other nozzle Fabrication complexity Can be used with many U heater although the normal drop e-ction mechanism clearing methods cannot be used series ink jts does not require it. The heaters do not require Can be implemented at no additional individual drive circuits, as many nozzles can cost in some inkjet configurations be cleared simultaneously, and no imaging is required. Nozzle plate construction Nozzle plate Description Advantages Disadvantages Examples construction Electroformed nicke A nozzle plate is separately fabricated from Fabrication simplicity High temperatures and pressures are required to bond Hewlett Packard Thermal elecrofonmed nickel, and bonded to the print nozzle plate Inkjet head chip. Minimum thickness constraints Differential thermal expansion Laser ablated or Individual nozzle holes are ablated by an No masks required Each hole must be individually formed Canon Bubblejet drilled poymer intense UV laser in a nozzle plate, which is Can be quite fast Special equipment required 1988 Sercel et al., SPIE, Vol. typically a polymer such as polyimide or Some control over nozzle profile is Slow where there are many thousands of nozzles per 998 Excimer Beam polysulphone possible print head Applications, pp. 76-83 Equipment required is relatively low May produce thin burrs at exit holes 1993 Watanabe et aL, USP cost 5,208,604 Silicon micro- A separate nozzle plate is micromachined from High accuracy is attainable Two part construction K. Bean, IEEE Tranactions on machined single crystal silicon, and bonded to the print High cost Electron Devices, Vol. head wafer. Requires precision alignment No. 10, 1978, pp 1185-1195 Nozzles may be clogged by adhesive Xerox 1990 Hawkins e al, USP 4,899,181 I Glass capillaries Monolithic, surface micro-machined using VLSI lithographic processes Fine glass capillaries are drawn from glass tubing. This method has been used for making individual nozzles, but is difficult to use for bulk manufactring of print heads with thousands of nozzles. The nozzle plate is deposited as a layer using standard VLSI deposition techniques. Nozzles are etched in the nozzle plate using VLSI lithography and.etching. No expensive equipment required Simple to make single nozzles I Very small nozzle sizes are difficult to form Not suited for mass production High accuracy pnm) Monolithic Low cost Existing processes can be used Requires sacrificial layer under the nozzle plate to form the nozzle chamber Surface may be fragile to the touch 970 Zoltan USP 3,683,212 Silverbrok, EP 0771 658 A2 and related patent applications JO01, J302, 104, 111 1)12,1 17, 1318, 1U22, 1124, 1127, 1J28 IJ29, 130, IJ31, 1132 1J33, 1134, 136, 1137 1)38, IJ39, 1140, IJ41 IJ42, 1343, 1)44 103, 1305, I106,1107 1308, U109, 1110, 1I13 IJl4, U15, 1116, 119 ,121, 1U23, 125, 126 Ricoh 1995 Sekiya et al USP 5,412,413 1993 Hadimiaglu et ai EUP 550,192 1993 Elrod et al EUP 572,220 3 i -4 I Monolidtic, etched through substrate The nozzle plate is a buried etch stop in the wafer. Nozzle chambers are etched in the front of the wafer, and the wafer is thinned from the back side Nozzles are then etched in the etch stop layer. High accuracy pmn) Monolithic Low cost No differential expansion Requires long etch times Requires a support wafer No nozzle plate Various methods have been tried to eliminate the nozzles etirely, to prevent nozzle clogging. These include thermal bubble mechanisms and acoustic lens mechanisms Each drop ejector has a trough through which a paddle moves. There is no nozzle plate. No nozzles to become clogged Reduced manufacturing complexity Monolithic Difficult to control drop position accurately Crosstalk problemsi Drop firing direction is sensitive to wicking. 'rough 1 I 1 48 Nozzle slit instead of The elimination of norle holes and No nozzles to become cogged Difficult to control drop position accurately 1989 Saito et a USP 4,799,068 individual enozles replacemenet by a slit encompassing many Crosstalk problems actuator positions reduces nozzle clogging, but increases crosstalk due to ink surface waves Drop ejection direction fjrtixon Direction Description Advantages Disadvantages Examples ~I Edge ('edge shooter') Surface ('roof shooter') Through chip, forward ('up shooter') Through chip, reverse ('down shooter') Through actuator Ink flow is along the surface of the chip, and ink drops are ejected from the chip edge. Ink flow is along the surface of the chip, and ink drops are ejected from the chip swuface, normal to the plane of the chip. Ink flow is through the chip, and ink drops are ejected from the front surface of the chip. Ink flow is through the chip, and ink drops are ejected from the rear surface of the chip. Ink flow is through the actuator, which is not fabricated as part of the same substrate as the drive transistors. Simple construction No silicon etching required Good heat sinking via substrate Mechanically strong Ease of chip handing No bulk silicon etching required Silicon can make an effective heat sink Mechanical strength High ink flow Suitable for pagewidth print High nozzle packing density therefore low manufacturing cost High ink flow Suitable for pagewidth print High nozale packing density therefore low manufacturing cost Nozzles limited to edge High resolution is difficult Fast color printing requires one print head per color Maximum ink flow is severely restricted Requires bulk silicon etching Canon Bubblejet 1979 Endo et al GB patent 2,007, 62 Xerox heater-in-pit 1990 Hawkins et at USP 4,899,181 'reon-jet Hewlett-Packard TU 1982 Vaught a a] USP 4,490,728 IJ02, IJ 11, 112, 1U20 1122 Silvexbrook, EP 0771 658 A2 and related patent applications U04, J1l7, 1118, 124 IJ27-IJ45 1301, 1303, 1105, U06 1307, 1J08, U109, 1310 1113, Ul4,1115, 116 1119,3 21, 123, 125 U126 Epson Stylus Tektronix hot melt piezoelectric ink jets Requires wafer thinning Requires special handling during manufacture Pagewidth print heads require several thousand connections to drive circuits Cannot be manufactured in standard CMOS fabs Complex assembly required Suitable for piezo lectric print heads -_111111~-- 1 _111~- a m, Ink t-- Ink type Description Advantages Aqueous, dye Aqueous, pigment Methyl Ethyl Ketone (MEK) Water based ink which typically contains: water, dye, surfactant, humectant, and biocide. Modenm ink dyes have high water-fastness, light fastness Water based ink which typically contains: water, pigment, surfahcan, humectant, and biocide. Pigments have an advantage in reduced bleed, wicking and strikethrough. Environmentally friendly Slow d No odor Conrrs 'antages rying ive on paper rikethrough s paper Irying ive at may clog noazles at may clog actuator mechanisms s paper Examples Environmentally friendly No odor Reduced bleed Reduced wicking Reduced strikethrough Very fast drying Prints on various substrates such as metals and plastics Most existing inkjets All J1 series ink jets Silverbrook, EP 0771 658 A2 and related patent applications 1102, I(04, 1J21, 126 UJ27, Silverbrook,,EP 0771 658 A2 and related patent applications Piezoelectric ink-jets 'hermal ink jets (with significant restrictions) All If series ink jets All I series ink jets MEK is a highly volatile solvent used for industrial printing on difficult surfaces such as aluminmm cans. Odorous Flammable Alcohol (ethanol, 2-butanol, and others) Phase change (hot meit) Alcohol based inks can be used where die printer must operate at temperatures below the freezing point of water. An example of this is in-camera consumer photographic printing. The ink is solid at room temperature, and is melted in the print head beforejetting. Hot melt inks are usually wax based, with a melting point around 80 After jetting the ink freezes almost instantly upon contacting the print medium or a transfer roller. Fast drying Operates at sub-freezing temperatures Reduced paper cockle Low cost Slight odor Flammable i No drying time- ink instantly freezes on the print medium Almost any print medium can be used No paper cockle occurs No wicking occurs No bleed occurs No strikethrough occurs High viscosity Printed ink typically has a 'waxy' feel Printed pages may 'block' ink temperature may be above the curie point of permanent magnets Ink heaters consume power Long warm-up time Tektronix hot melt piezoelectric ink jets 1989 Nowak USP 4,820,346 All 1 series ink jets 11111~--- Microemulsion i YIIIII~- lllll_ Oil based inks are extensively used in offset printing. They have advantages in improved characteristics on paper (especially no wicking or cockle). Oil soluble dies and pigments are required. A microenmulsion is a stable, self forming emulsion of oil, water, and surfactant. The characteristic drop size is less than 100 rm, and is determined by the preferred curvature of the surfactant. I High solubiliy medium for some dyes Does not cockle paper Does not wick through paper Stops ink beed High dye solubility Water, oil, and amphiphilic soluble dies can be used Can stabilize pigment suspensions ~1~-~11~11~111~ I High viscosity: this is a significant limitation for use in inkjets, which usually require a low viscosity. Some short chain and multi-branched oils have a sufficiently low viscosity. Slow drying Viscosity higher than water Cost is slightly higher than water based ink High surfactant concentration required (around All 1J series ink jets All J series ink jets I