Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
  • B41J—TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
  • B41J2/00—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed
  • B41J2/22—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by selective application of impact or pressure on a printing material or impression-transfer material
  • B41J2/23—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by selective application of impact or pressure on a printing material or impression-transfer material using print wires
  • B41J2/235—Print head assemblies
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
  • B41J—TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
  • B41J2/00—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed
  • B41J2/435—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by selective application of radiation to a printing material or impression-transfer material
  • B41J2/447—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by selective application of radiation to a printing material or impression-transfer material using arrays of radiation sources
  • B41J2/45—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by selective application of radiation to a printing material or impression-transfer material using arrays of radiation sources using light-emitting diode [LED] or laser arrays
• • G—PHYSICS
  • G06—COMPUTING OR CALCULATING; COUNTING
  • G06K—GRAPHICAL DATA READING; PRESENTATION OF DATA; RECORD CARRIERS; HANDLING RECORD CARRIERS
  • G06K15/00—Arrangements for producing a permanent visual presentation of the output data, e.g. computer output printers
  • G06K15/02—Arrangements for producing a permanent visual presentation of the output data, e.g. computer output printers using printers
  • G06K15/12—Arrangements for producing a permanent visual presentation of the output data, e.g. computer output printers using printers by photographic printing, e.g. by laser printers
  • G06K15/1238—Arrangements for producing a permanent visual presentation of the output data, e.g. computer output printers using printers by photographic printing, e.g. by laser printers simultaneously exposing more than one point
  • G06K15/1242—Arrangements for producing a permanent visual presentation of the output data, e.g. computer output printers using printers by photographic printing, e.g. by laser printers simultaneously exposing more than one point on one main scanning line
  • G06K15/1247—Arrangements for producing a permanent visual presentation of the output data, e.g. computer output printers using printers by photographic printing, e.g. by laser printers simultaneously exposing more than one point on one main scanning line using an array of light sources, e.g. a linear array

Definitions

• the present invention relates to an optical head and, more particularly, to an optical head having two or more rows of light emitting points, and more particularly to a method of lighting such an optical head.
• the optical print head is a light source for exposing the photosensitive drum to light, and has a light emitting point array composed of a light emitting element array.
• Figure 1 shows the configuration of an optical printer with an optical printer head.
• a photoconductive material photoreceptor
• This drum rotates at the print speed.
• the surface of the rotating drum is charged uniformly by the charger 4.
• the photo print head 6 irradiates the photoreceptor with the light of the dot image to be printed, and neutralizes the charge at the time of the light.
• the transfer device 10 transfers the toner onto the paper 14 sent from the cassette 12.
• the toner is heated and fixed by a fixing device 16 on paper, and the paper is sent to a scanner 18.
• the drum after transfer is erased
• the charge is neutralized over the entire surface, and the remaining toner is removed at the cleaner 22.
• Figure 2 shows the structure of the optical printer head 6.
• the optical head includes a light emitting element array 24 and a rod lens array 26, and the focal point of the lens is focused on the photosensitive drum 2.
• a light emitting point array is composed of a single line of light emitting elements arranged in a line.
• An optical printer consisting of a single row of light emitting points Evening head has the following problems.
• the amount of exposure of one pixel is determined by the amount of light from one lit point. Therefore, it is not possible to increase the exposure amount of one pixel in the optical head of the light emitting point in one row.
• the pixel density is determined by the pitch of the light emitting points. Further, the arrangement pitch of the light emitting points is limited by the manufacturing conditions of the light emitting element array. Therefore, there is a limit in increasing the pixel density in an optical printer head having a single light emitting point array.
• the light-emitting element array is manufactured by arranging a plurality of light-emitting element array chips, but the light spot array deviates from a straight line because the chips are mounted at an angle. Sometimes. Disclosure of the invention
• An object of the present invention is to provide an optical printer head capable of increasing the exposure amount of one pixel.
• Another object of the present invention is to provide an optical printer head capable of increasing the pixel density.
• Still another object of the present invention is to provide an optical head capable of correcting a shift of a light spot array on a photosensitive drum.
• Still another object of the present invention is to provide a method of lighting such an optical head.
• an optical head for exposing a photosensitive drum to form a pixel, a light emitting element array having two or more light emitting point arrays, and light from the light emitting element array On the photosensitive drum And a rod lens array for projecting light spots to form a light spot sequence.
• the two or more light emitting point arrays have the same pitch in the main scanning direction parallel to the rotation axis direction of the photosensitive drum, and the light emitting points of each light emitting point array are orthogonal to the rotation direction of the photosensitive drum. Preferably, they are arranged so as to be arranged in the sub-scanning direction, or they are arranged so as to be shifted in the main scanning direction.
• Each of the light emitting point arrays can be an array of light emitting diodes or an array of three terminal light emitting diodes.
• the array of the three-terminal light-emitting thyristor can be constituted by the light-emitting part of the self-scanning light-emitting element array.
• the self-scanning light-emitting element array includes a plurality of three-terminal light-emitting thyristors having a control electrode for a threshold voltage or a threshold current for a transfer operation as transfer elements, and the control of each transfer element is performed.
• the electrode is connected to the control electrode of at least one transfer element located in the vicinity of the electrode via an electrically unidirectional electrical element, and a power supply line is connected to the control electrode of each transfer element.
• a transfer section formed by connecting a clock pulse line to each transfer element.
• a light-emitting section in which a plurality of three-terminal light-emitting thyristors having a control electrode for a threshold voltage or a threshold current for light-emitting operation are arranged as light-emitting elements, and each control electrode of the light-emitting element is arranged
• a line is provided which is electrically connected to a control electrode of the transfer element and supplies a current for light emission to each light emitting element.
• a light emitting element array having two or more light emitting point arrays, and a rod for forming light spot arrays by projecting light from the light emitting element array onto the photosensitive drum.
• the two or more light emitting point arrays have the same pitch in the main scanning direction parallel to the rotation axis direction of the photosensitive drum, and the light emitting points of each light emitting point array are Optical pumps are arranged in a sub-scanning direction that is orthogonal to the drum rotation direction.
• the lighting amount of the plurality of light emitting points arranged in the sub-scanning direction is selected to change the cumulative exposure amount of the pixel.
• the light amounts of the light emitting points of the two or more light emitting point arrays can be all the same or can be changed in light emitting point array units.
• lighting of the light emitting points of the two or more light emitting point arrays can be selected so as to correct the shift of the light point array on the photosensitive drum.
• FIG. 1 is a diagram showing a configuration of an optical printer having an optical printer head.
• Figure 2 is a diagram showing the structure of the optical head.
• FIG. 3 is a diagram illustrating an LED array chip having two light emitting point arrays.
• FIG. 4 is a diagram illustrating a state in which a photosensitive drum is exposed while rotating in a sub-scanning direction.
• FIG. 5 is a diagram showing another state in which the photosensitive drum is exposed while rotating in the sub-scanning direction.
• FIG. 6 is a diagram showing another example of an LED array chip used for an optical printer head.
• FIG. 7 is a diagram showing a state in which the light spot sequence after passing through the load lens is deviated from a straight line due to the influence of the undulation of the load lens.
• FIG. 8 is a diagram showing an example in which the displacement of the light spot sequence in FIG. 7 has been corrected.
• FIG. 9 is a diagram showing an excavation circuit of the self-scanning light emitting element array.
• FIG. 10 is a diagram showing a chip of the self-scanning light emitting element array shown in FIG. BEST MODE FOR CARRYING OUT THE INVENTION
• FIG. 3 shows a light emitting diode (LED) array chip 30 used in an optical printer head, which has two light emitting points, a first row and a second row.
• 32 indicates a bonding pad
• 34 indicates a light emitting point.
• P indicates the pitch of the light emitting point in the main scanning direction
• d indicates the pitch of the light emitting point in the sub scanning direction.
• the main scanning direction is a direction parallel to the rotation axis of the photosensitive drum
• the sub-scanning direction is a direction perpendicular to the rotation axis of the photosensitive drum. Note that d is selected to be an integral multiple of the resolution in the sub-scanning direction.
• FIG. 4 shows how the photosensitive drum is exposed by two rows of light emitting points while the photosensitive drum rotates in the sub-scanning direction.
• one cell represents one pixel
• the light-filled cells in the light bridging head 6 indicate light-emitting points.
• the numbers “0” indicate pixels that were not exposed, “1” indicates pixels that were exposed once, and “2” indicates pixels that were exposed twice.
• the first exposure is performed by exposing the first row of light emitting points 6A
• the second exposure is performed first by the first row of light emitting points 6A.
• the pixel is subsequently exposed to light in the second light emitting point row 6B.
• the cumulative exposure amount of the pixel is up to twice as large as that of the conventional light emitting point having one row, so that the printing speed is reduced to the conventional one. It can be doubled.
• the optical printer head having two rows of light emitting points is shown, but three or more rows may be provided.
• Figure 5 shows another example of exposure using a head having two rows of light emitting points.
• the first and second rows of light emitting points had the same light intensity.
• the light quantity at the light emitting points in the second row was twice as much as the light quantity at the light emitting points in the first row.
• the light print head having two rows of light emission points is shown, but light emission points of three or more rows may be used.
• FIG. 6 shows another example of an LED array chip 36 used for an optical printer head.
• 32 is a bonding pad
• 34 is a light emitting point.
• an LED array chip 36 having first and second two light-emitting point arrays arranged at a pitch p in the main scanning direction and a pitch d in the sub-scanning direction is used. ⁇ Configure the code.
• the first and second rows of light emitting point arrays are arranged so as to be shifted by a half pitch (p / 2) in the main scanning direction as shown in the figure.
• the pitch d in the sub-scanning direction of the emission point sequence is selected so as to be an integral multiple of the resolution in the sub-scanning direction.
• the light emitted from the light emitting element array 24 passes through the rod lens array 26 and is incident on the photosensitive drum 2.
• the load lens array 26 is configured by, for example, stacking the load lenses 50 in a bale as shown in FIG.
• Light emitted from a single light emitting point array 40 composed of an array of LEDs 39 passes through an aperture lens array 26.
• the light after passing is on photosensitive drum 2.
• To form a sequence of light spots 42 (each light spot is indicated by 41).
• the light spot array 42 may be deviated from a straight line due to the influence of the undulation of the rod lens array 26.
• the LED array of the light source is composed of a plurality of light emitting point arrays.
• FIG. 8 shows an embodiment including an LED array 44 composed of four light emitting point arrays.
• two adjacent light emitting points in the sub-scanning direction emit light at the same time, thereby enabling three-step position adjustment of the light spot.
• the hatched portions indicate two adjacent light-emitting points that emit light simultaneously.
• hatched portions indicate light that passes through the rod lens array 26 and enters the photosensitive drum 2.
• the LED array was used as the light emitting element array.
• the self-scanning light emitting element array using the three-terminal light emitting array is connected to the optical printer head. The case where it is used for will be described.
• FIG. 9 shows an equivalent circuit of the self-scanning light-emitting element array of this embodiment.
• This self-scanning light-emitting element array is disclosed in Japanese Unexamined Patent Publication No. Hei. Is what it is. The contents of this publication shall be included in the contents of this specification.
• the self-scanning light-emitting element array in FIG. 9 basically includes a transfer section 60, a first light-emitting section 62, and a second light-emitting section 64.
• the first light emitting section 62 corresponds to the first light emitting point sequence in the above-described embodiment
• the light emitting section 64 corresponds to a second light emitting point sequence.
• Transfer section 6 as a transfer element, three-terminal light-emitting Sai Li scan evening ..., T. 15 T 0, T! ,... Are used.
• Each of the light-emitting Sai Li scan evening of the gate electrode ..., G. 15 G. ,,... are connected to the power supply voltage V GA via the load resistance RL.
• the first light emitting portion 6 2 and the second light emitting portion 6 4 respectively, as a light emitting element for writing, 3-terminal light emitting reused scan evening ( ⁇ , L 1. 15 L l ., L 1 J, ⁇ ), (..., L 2. 13 L 2., L 2!, Ri Do Ri by an array of 7), the light-emitting part 6 2, 6 4 each of the light-emitting rhino re-scan the evening of the gate of the
• the electrode is connected to the gate electrode of the light emitting thyristor of the transfer unit 60.
• Light emission thyristor, L1, L1. , L 1,, ... of the power source cathode electrode, light emission Sai Li scan evening ..., L 2. 15 L 2. , L 2,... Are applied with write signals 1 and ⁇ 2, respectively.
• the transfer clock 01 is at a low level and the light emitting thyristor T D is on.
• the gate electrode G is determined based on the characteristics of the three-terminal light emitting thyristor. Is raised to near zero volts. This a tree, the resistor R L, diode ..., D. There D 0, D!
• the gate voltage of each light emission thyristor is determined from the network of,.... And the light emitting thyristor T.
• the gate electrode Gi is G. Is set to a voltage lower by the forward rise voltage V dlf of the diode , and the gate electrode G 2 is connected to G i with respect to G i. In addition, the voltage is set to a voltage lower by the diode rising voltage V dlf .
• light emitting thyristor T The left of the gate electrode does not flow current because Daio one de D ⁇ are reversed biased, Therefore the power supply voltage V CA with the same potential.
• Next transfer click Lock Kuparusu 2 has recently emitting reuse scan tangent evening ⁇ ⁇ , ⁇ . 13 is applied to its to T 3 and ⁇ .3 like, among these, most evening one N'on
• the light-emitting thyristor with a high voltage is 1, and the on-state voltage of the light-emitting thyristor is the gate voltage of the gate electrode + V dlf , which is about twice V dlf .
• high luminous reused scan evening of the turn-on voltage is Ri T 3 der, is about four times the V dlf.
• the turn-on voltage of 1 ⁇ is approximately V GA + V dif .
• a low level voltage of the transfer click Lock Kuparusu by setting between about two times the V dlf approximately four times the V dlf, and this to turn on only the light-emitting reused scan evening T i Transfer operation can be performed.
• the gate electrode is about 15 volts, and the gate electrode Gi is about 11 volts. Therefore, the write voltage for the light emitting thyristor L1 is about -6 volts, and the write voltage for the light emitting thyristor is about -2 volts. From now on, the light emitting thyristor L1. The voltage of the write signal 1 that can be written only in the range of about 11 to 12 volts. Light emitting thyristor L L. When the light is turned on, that is, when the light emission state is entered, the error that another light emission thyristor is selected can be prevented.
• the light emission intensity is determined by the amount of current flowing in the write signal 1, and Image writing becomes possible with the intensity.
• the voltage of the write signal 1 ⁇ 1 must be once reduced to 0 volt, and the light emitting element must be turned off for a while. It is necessary.
• the operation of the second light-emitting unit 64 is the same as the operation of the first light-emitting unit 62, and will not be described again.
• FIG. 10 is a diagram showing a chip 110 of the self-scanning light-emitting element array shown in FIG.
• a transfer section 60 two rows of light emitting points 62, 64, and a plurality of bonding pads 70 are formed.
• Such a self-scanning light-emitting element array can be used for an optical head as in the LED array shown in FIG.
• the light emitting points and the bonding pads are connected in a one-to-one relationship.
• the light emitting element array for example, if the number of light emitting point arrays increases, only one bonding pad needs to be added, so that there is an advantage that the chip size is not increased.

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• Physics & Mathematics (AREA)
• Optics & Photonics (AREA)
• Engineering & Computer Science (AREA)
• General Engineering & Computer Science (AREA)
• General Physics & Mathematics (AREA)
• Theoretical Computer Science (AREA)
• Health & Medical Sciences (AREA)
• General Health & Medical Sciences (AREA)
• Toxicology (AREA)
• Printers Or Recording Devices Using Electromagnetic And Radiation Means (AREA)

Priority Applications (2)

Applications Claiming Priority (2)

Publications (1)

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Cited By (2)

Families Citing this family (14)

Citations (3)

Family Cites Families (3)

• 2000
  • 2000-03-16 JP JP2000073530A patent/JP4543487B2/ja not_active Expired - Fee Related
• 2001
  • 2001-03-15 EP EP01912382A patent/EP1186428A4/en not_active Withdrawn
  • 2001-03-15 CA CA002374034A patent/CA2374034A1/en not_active Abandoned
  • 2001-03-15 WO PCT/JP2001/002043 patent/WO2001068373A1/ja not_active Ceased
  • 2001-03-15 CN CN01800475A patent/CN1364117A/zh active Pending
  • 2001-03-15 TW TW090106040A patent/TW562753B/zh not_active IP Right Cessation
  • 2001-03-15 KR KR1020017014504A patent/KR100781910B1/ko not_active Expired - Lifetime
  • 2001-03-15 US US10/048,706 patent/US20030007064A1/en not_active Abandoned

Patent Citations (3)

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