JPS6336768Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a film image converting apparatus, and more particularly to a film image converting apparatus for electronically scanning a film and displaying it on a television receiver.

A conventional device that includes a film projection device that continuously drives a Super 8 film and electronically scans the Super 8 film and displays it on a color television receiver (Funkschau 1974, Vol. 9, pp. 292-298)
In this case, film scanning is performed using a scanning tube. In this case, a mirror arrangement with two dichroic mirrors and three color filters is provided to generate the red, green, and blue signals necessary to control the color picture tube, and the mirror arrangement has three optoelectronic mirrors. Acts on multiplier tubes. However, this device is mechanically very expensive.

Furthermore, in order to generate a video signal for a black-and-white image receiver, a photodiode array, i.e., a charge-coupled device (CCD) having a row of image sensor elements arranged in the projection plane of a projection device in a direction transverse to the direction of film movement, has been considered. It is being However, it has hitherto been impossible to control a color television receiver using such a device.

The object of the invention is, therefore, to provide a device of the kind described above, which is capable of electronically scanning Super 8 film and displaying the resulting color video signal on a color television receiver in a simple manner. An object of the present invention is to provide a film image conversion device.

According to the present invention, for each scanning point of a photodiode array, three image sensor elements are successively arranged in the length direction of the array to scan a Super 8 film, and each of the image sensor elements is a red one. , configured to be sensitive to green and blue. Each of these image sensor elements is also connected in series to a register device.

This allows a single photodiode array with three times as many image sensor elements to generate a color video signal as compared to a conventional black and white device. In particular, the color separation of each image point by three image sensor elements sensitive to red, green and blue, arranged one behind the other along the length of the array,
It is suitable for modern in-line color television picture tubes in which the three colors of the image points are similarly reproduced in one line.

The electrical signal corresponding to one television line is obtained by the continuous movement of the charges applied in parallel to the register arrangement from the individual image sensor elements of the photodiode array. To have multiple image lines, the projection of the film image is controlled and moved over the photodiode array in synchronization with the vertical frequency of the film image.

The register device consists of one analog shift register, in which a row of image sensor elements, each arranged sequentially red, green, blue, is connected to the analog shift register via a storage capacitor, so that the red , green and blue color scanning signals can be stored and transferred in parallel to an analog shift register, while the output of the analog shift register is connected to a time division output switching circuit from which red, green and blue signals are obtained, A simple configuration consisting of one row of photodiode arrays and one analog shift register allows the photodiode array to be placed on the projection plane of the projection device in a direction transverse to the direction of film movement, and converts film scanning signals into color video signals in a simple manner. can do.

In another embodiment, the shift register has three analog shift registers, each of which is connected in series with an image sensor element having the same color sensitivity, so that the output of each of the three analog shift registers is Three color signals are generated. With this configuration, three analog shift registers can be combined into one
This requires a considerable amount of IC technology as it must be installed on the CCD chip, but in return the clock frequency can be reduced to 1/3.

Each image sensor element of the photodiode array is formed to have a different color sensitivity by depositing various interference layers in alternating succession using IC techniques in conventional mask manufacturing.

According to another embodiment, the image sensor elements of the photodiode array are made red, green and blue sensitive by coating them with a strip filter.

A transfer gate is preferably provided between the two to transfer the charge obtained from the image sensor elements of the photodiode array in parallel to the register arrangement.

Further, in accordance with an embodiment of the invention, the projection device has an oscillating mirror system which vertically deflects the image of the film image at a frequency necessary for television reception, taking into account the transport speed of the film. In this case, the amount of movement of the vibrating mirror corresponds to 2/3 of the height of the film image, since the film image moves in the same way.

As the oscillating mirror system, a oscillating mirror known from the field of galvanometer technology is used, since only a few structural changes are required with respect to the magnetic block. By using such an oscillating mirror system, the high requirements necessary for film scanning are met.

The vibrating mirror system preferably has a galvanometer oscillator. The oscillator of this oscillating mirror system is preferably controlled via a summing logic circuit and an amplifier.

Also, in order to be able to utilize large area galvanometric oscillating mirrors at critical frequencies in the periodic range of the deflection frequency, a second wave generator controlled by a sawtooth wave generator generates short return acceleration pulses during the return movement. A second pulse generator is provided which is also controlled by a sawtooth generator and which generates short controlled acceleration pulses, the sum of the pulse durations of both pulses being equal to that required for television reception. The vertical blanking time is not exceeded. Furthermore, an adjustment device is provided in the summing logic circuit, by means of which the sawtooth voltage as well as the amplitudes of the two pulses can be adjusted independently of each other.

Preferably, the sum of the pulse durations of both pulses of the pulse generator does not exceed 1.2 msec.

With this configuration, even if a vibrating mirror with a relatively large area is used, the transient phenomenon during retrace can be completed after 1.2 msec at the latest. By means of a vibrating mirror system, the projected image of the film image is moved in the vertical direction at a frequency required for television reception, for example 50 Hz. In this case, the retrace time of each image is made to correspond at most to the vertical retrace time required for television reception, that is, 1.2 msec. In this case, the upper limit frequency of the oscillating mirror system is selected so that the retrace transient ends after 1.2 msec at the latest. This occurs after _1/0 time in a critically damped system. However, ₀ is the natural resonance frequency of the vibration system. However, galvanometer oscillators are usually designed to have a damping rate of 0.7 and therefore have only a small amount of overshoot.
The transient phenomenon ends after approximately 1.5/ ₀ time has elapsed.
This means that the natural resonance of the vibration system must be at least min=1.5/1.2msec=1.25kHz.

Furthermore, according to an embodiment of the invention, the first pulse generator for return acceleration consists of one monostable multivibrator, and the second pulse generator for braking and scanning acceleration consists of two monostable multivibrators. The temporal position and duration of the output pulses are adjusted independently of each other using two potentiometers.

By configuring in this way, the electronic circuit can be configured very easily and a complicated control circuit can be omitted. On the other hand, there is a method in which a position detector is provided on the vibrating mirror and the position detector is moved in the same way as the vibrating mirror to generate a voltage proportional to the movement.In that case, the current value of the vibrating mirror position is continuously There are methods in which a voltage proportional to the desired value of the position is compared and the deviation between the current value and the desired value is applied as a control voltage to the oscillating mirror system via an intensifier. The present invention makes it possible to avoid the use of conventional control circuits which have drawbacks at the beginning and end of vibration.

Detailed embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

FIG. 1 shows an apparatus for electronically scanning Super 8 film for display on a color television. This device has an illumination drive device 1 that illuminates a Super 8 film with a projection lens, a vibrating mirror system 2, and an image sensor device 3. This image sensor device 3 separates each image point into colors and electronically sends an image signal. consists of a photodiode cell that processes
It has a CCD (charge coupled device).

The lighting drive device 1 is controlled by a phase comparator 4 . The oscillating mirror system 2 has an oscillator S, which is controlled via a summing logic circuit 5 and an amplifier 6.

An amplifier 7 is connected to the output of the image sensor device 3, the output of which is connected to a decoder logic circuit 8. . Red, green and blue signals appear at the three outputs of this decoder logic circuit 8, respectively, and these signals are applied to the encoder unit 13 via amplifiers 10, 11 and 12, respectively.
The encoder unit 13 has a color composite signal encoder E, an HF (high frequency) modulator H and a high frequency oscillator C. Encoder unit 13
The output is directed to a color television.

A reference clock frequency generator 9 is provided for controlling the phase comparator 4, the summing logic 5, the image sensor device 3, the decoder logic 8 and the encoder unit 13.

The lighting driving device 1 has the same structure as a normal Super 8 projector, but there are some differences. That is, the Super 8 film is driven by a drive wheel (capstan shaft) or by gears that engage the perforation of the film and continuously transport it. The phase of the individual Super 8 films relative to the phase of the oscillating mirror device 2 is measured and adjusted by the electronics of the phase comparator 4. To measure the phase of a Super 8 film, it is preferable to use a small detector L to detect film perforation.

The image change frequency is not 18 or 24 frames per second, but an integer fraction of the television vertical frequency of 50 Hz, or 162/3 to 25 frames per second.
In the case of film reproduction, even if the time is slightly lengthened or shrunk, the quality of the reproduced image will not deteriorate.

The film image is produced by the vibrating mirror system 2 at a repetition frequency of 50, which is specified for television.
Hz (in Germany) shifted vertically.
In this case, the blanking time between each image is at most the vertical blanking time specified in television.
That is, it must be 1.2ms. For such a vibrating mirror system, a vibrating mirror system known in the field of galvanometers is suitable. In this case, the upper limit frequency must be chosen such that the transient in the return line ends after 1.2 ms at the latest. . This is obtained after _1/0 time has elapsed in the case of a critically damped vibrator. However, ₀ is the natural resonance frequency of the vibration system. Ordinary galvanometer transducers have a damping rate of
0.7, that is, the overshoot is designed to be slight, so the transient phenomenon ends after t=1.5×1/ ₀ has elapsed. This means that the natural resonant frequency of the vibration meter must be at least min=1.5/1.2msec=1.25kHz. in this case
It is known that galvanometer oscillators with a frequency of ₀ = 15kHz are commercially available.

The oscillator S is controlled via a summing logic circuit 5 and an amplifier 6. Figure 2 shows the composite sawtooth wave signal required to scan Super 8 film shot at 18 frames per second. A deflection voltage curve such as that shown in FIG. 2 can be easily obtained by adding a simple sawtooth wave voltage and a square wave voltage. By pre-emphasizing the other sawtooth voltages, tangential errors in the scan can be compensated for, for example.

To better understand the movement of the oscillating mirror, the instantaneous film position occurring after each 20 ms, ie after each image scan (for each field), is shown in each case.

If t ₁ =0, the oscillating mirror is in such a position that the first line L ₁ of the associated image (image A in FIG. 3) is projected onto the photodiode array of the image sensor device 3. The film is moved down by 1/3 of the image height after 20 msec, in which case the movement of the oscillating mirror is positioned such that exactly the last line _L2 of image A is projected onto the photodiode array after 20 msec. . Therefore, the movement of the vibrating mirror is 2/of the image height.
3, and the remaining 1/3 is given by the movement of the film.

The amount of return of the vibrating mirror corresponds to the width of the entire image, as indicated by the dotted line with the sawtooth wave voltage that represents the control voltage of the vibrating mirror. No return of the oscillating mirror occurs after the third image scan is completed, ie after t ₁ =60ms. This is because the last line L ₂ of the first image A is the first line L ₃ of the second image B.
This is because it is approximately equivalent to . (L ₄ indicates the first line of the second image B). If there is a slight difference in position between these two lines, adjustment can be made by applying a corresponding rectangular wave voltage. The actual course of the oscillating mirror movement, including transient phenomena, is illustrated in dotted lines in FIG. Third
The image window of the illumination device is designated F in the figure.

Regarding the image sensor device 3 with a CCD device consisting of a photodiode array and the associated decoder logic circuit 8 for decoding the trichromatic color signals of red, green and blue, up to the color signals modulated on a high frequency carrier wave. It is sufficient to describe these elements since signal processing is well known from television technology.

FIG. 4 shows an embodiment of the image sensor device 3 which obtains color signals using a time division input switching circuit. The CCD, or charge coupled device, has a photodiode array 14 connected to an analog shift register 16 via a transfer gate 15. A clock generator U that generates a clock signal T
The clock is run by A charge amplifier 17 is provided at the output of the analog shift register 16, at the output of which a serial color signal A containing all color components of each image point is generated. This color signal A is applied to a three-channel output switching circuit 18, and color signals R, G, and B are obtained at the outputs of the output switching circuit, respectively. The control of this output switching circuit 18 is as shown in FIG.
This takes place via a decoder logic circuit 19 with a bit counter Z and associated logic gate circuits. When Q ₁ and Q ₂ are both zero, it is red,
When Q ₁ is “1”, Q ₂ is “0”, it is green, Q ₁ is “0”,
When Q ₂ is "1", you get blue. Figure 5 is the 4th
3 is a clock pulse diagram of the circuit shown in the figure; FIG.

The photosensitive part of the CCD consists of a photodiode array 14 having, for example, 1200 silicon photodiodes arranged in a row at a distance of 13μ, the total width of the array being 15.6mm. The lens of the illumination driving device 1 is configured so that one line of the Super 8 film is expanded to the width of the photodiode array 14. The distance between the oscillating mirror and the photodiode array 14 is chosen such that the maximum projection movement required is 11/3 times the image height so as not to exceed the allowable deflection angle of the oscillating mirror system. In addition, this distance must be selected as much as possible in order to minimize the tangent error during projection, that is, the amount of deviation from the horizontal.

For example, in FIG. 3, when t ₁ =0, if the first line of image A is projected onto the photodiode array 14 (FIG. 4), the transfer gate 15 becomes conductive instantaneously at the rising edge of the pulse. ,
The luminance signals stored there (a storage capacitor is connected to each image sensor element of the photodiode array) are transferred in parallel onto an analog shift register 16. That is, the temporally serial red, green, and blue color scanning signals are transferred in parallel to an analog shift register. From this point on, the signal stored in the analog shift register 16 is sent to the outside by the clock pulse T.
It is transferred to the output of the CCD via a charge amplifier 17.

The frequency of the clock pulses T is chosen such that the contents of the analog shift register 16 are transferred out during exactly the transit time of the television line (52.5 .mu.sec). When playing back in black and white, this signal becomes exactly the image signal, which is processed as a video signal in the usual way. A photodiode array with about 400 image sensor elements is sufficient in this case. For color reproduction, a method known in color television technology of color separation using dichroic mirrors and color filters and three photodiode arrays are used to obtain three color components from each image point.

However, in the embodiment described above, one photodiode array 14 with three times as many elements is used.
is used. To this end, the image sensor element can be deposited during the manufacturing process in such a way that an interference layer is formed (such masks are well known in the IC technology field) or by subsequent provision of a strip filter. It is possible to sequentially impart photosensitivity to red, green and blue. Each image point is thus composed of three color elements adjacent to each other. This is particularly preferred for current in-line color television picture tubes. This also results in the reproduction of an image point consisting of three adjacent colors red, green and blue.

At the output of the CCD, a continuous color signal A is obtained having the red, green and blue components of each image point alternately every three clocks. This signal is converted into color signals R, G, B in parallel using a three-channel output switching circuit 18 and its associated decoder circuit 19. The output switching circuit 18 divides the signal A into respective outputs R, G and B, in which case these signals are stored in a capacitor, for example, until the next image point information appears. The frequency of the clock generator is chosen so that the contents of the analog shift register 16 are guided out in the transit time of the television line (52.5 .mu.sec), as already mentioned. Thus, for example, if a 1200 photodiode array is used, the clock frequency of the clock generator U will be _T = 1200/52.5 x 10 ^-6 Hz = 23 MHz. CCDs with clock frequencies of this magnitude are already commercially available.

Another embodiment of the image sensor device is illustrated in FIG. 6, in which the clock frequency can be lowered but requires three analog shift registers for the CCD device, making it more sophisticated.
Requires IC technology.

CCD photodiode array 20 is the same as photodiode array 14 shown in FIG. However, in FIG. 6, signals from image sensor elements or photodiodes having the same color sensitivity are applied to analog shift registers 22, 23, 24 via transfer gates 21, respectively. .
Therefore, in this case, shift registers for the photodiodes sensitive to red, green, and blue are required, and the voltages from the photodiodes are generated simultaneously and in parallel at each position of the shift register through the transfer gate 21. Ru.

The same clock is used when extracting the charge from the three analog shift registers 22, 23, 24 via charge amplifiers 26, 27, 28, so that the color signals R, G, B are paralleled to the three outputs of the CCD. occurs in These color signals are processed to produce color signals according to signal processing known in the television art. The required clock frequency in this case is just 1/3 lower than in the case of the image sensor arrangement described in connection with FIG. 4, since with each clock pulse T an image point with complete color information is obtained from the analog shift register. becomes smaller.
In the case of 1200 photodiodes, the clock frequency of the clock generator U is _T =400/52.5× _{10 -6} ^Hz =7.5MHz. Figure 7 shows the amount of movement φs of the vibrating mirror required to change the vertical direction when projecting a film image onto the photodiode line. Each television field is scanned. As is clear from Fig. 7, with the configuration of the present invention, the transient phenomenon in the retrace line is 1.2 msec at the latest.
Since it ends later, the lower extremum of the curve is directly followed by the linear part of the curve. On the other hand, curve a shown as a dotted line shows the transient phenomenon of the oscillating mirror when the brake is very large, curve b shows the curve when the control is weak, and curve c shows the curve when the acceleration is too weak in the case of retrace. The curves for each case are shown.

After the scanning movement of the vibrating mirror is completed, a large negative pulse is required to significantly accelerate the vibrating mirror in the return direction. The energy supplied is then limited due to the electromechanical configuration of the vibration system. This negative pulse causes the vibrating mirror to have a very high speed at the end of the retrace. The oscillating mirror must now be braked rapidly and must be accelerated in the opposite direction to obtain the required scanning speed. The braking and acceleration to achieve this scanning speed are obtained by a positive voltage pulse 110 immediately following a negative voltage pulse 109. By precisely adjusting the amplitude and duration of this positive pulse as well as its position in time, it is possible to bring the oscillating mirror up to scanning speed without overshooting it too quickly. That is, the desired sawtooth motion is achieved, with the scanning speed and return speed being quite different. 8th
In the figure, the deflection voltage Us of the mirror is plotted against time t.

FIG. 9 is a block diagram of a circuit for obtaining the control voltage Us shown in FIG. 8. A sawtooth wave generator 101 that performs a linear scanning motion as well as a rapid return motion sends short pulses to a pulse generator 102 during its return motion to obtain return acceleration, and to a pulse generator 102 for braking and obtaining scanning acceleration. Similarly, a short pulse is applied to 103. The pulse generator 102 consists of a monostable multivibrator, for example, so that the duration of the output pulses can be easily adjusted. The pulse generator 102 can also be constructed using two monostable multivibrators, in which case the temporal position of the output pulse as well as its pulse width can be adjusted independently of each other using two potentiometers. is possible. The sawtooth voltage as well as the square wave pulses obtained from the pulse generators 102, 103 are led to a summing logic circuit implemented by a summing amplifier 104, where the amplitude of the voltage is determined by means of potentiometers 105, 106, 107, etc. It can be adjusted using an adjustment device. The summing amplifier 104 also becomes the final stage of the galvanometer oscillating mirror 112. Summing amplifier 104 is preferably provided with a current limiter to protect the oscillating system.

[Brief explanation of drawings]

Each figure shows an example of the present invention.
Figure 1 is a schematic layout diagram showing the configuration of each device used to electronically scan film;
The figure is a voltage waveform diagram supplied to the vibration system of the apparatus shown in Figure 1, Figure 3 is an explanatory diagram showing the relationship between the vibration system of the apparatus shown in Figure 1 and the movement of the film, and Figure 4 is used in the apparatus shown in Figure 1. 5 is a pulse waveform diagram showing the pulse waveform obtained at each part in response to a clock pulse in the circuit of FIG. 4. FIG. 6 is a block circuit diagram showing the decoder logic circuit used in FIG. 1. A block circuit diagram showing another embodiment of the circuit, Fig. 7 is a characteristic graph showing the scanning motion of the vibrating mirror of the device shown in Fig. 1, and Fig. 8 shows the voltage required to obtain the curve shown in Fig. 7. FIG. 9 is a voltage waveform diagram showing waveforms, and FIG. 9 is a block circuit diagram showing a circuit for controlling the vibrating mirror. 1...Lighting drive device, 2...Vibrating mirror system, 3
...Image sensor device, 4...Phase comparator, 5...
... Addition logic circuit, 8 ... Decoder logic circuit, 9 ...
... Reference clock generator, L ... Detector, S ... Galvanometer oscillator, E ... Synthetic color signal encoder, H ... High frequency modulator, 14 ... Photodiode array, 15 ... Transfer gate, 16
... Analog shift register, 18 ... 3-channel output switching circuit, 20 ... Photo diode array, 22, 23, 24 ... Analog shift register, U ... Clock generator, 101 ... Sawtooth wave generator, 102, 103...Pulse generator, 104...Summing amplifier, 105, 106, 1
07... Potentiometer, 112... Galvanometer vibrating mirror.

Claims (1)

[Claims for Utility Model Registration] 1. A projection device that continuously drives and projects a film, a row of photodiode arrays arranged in a direction intersecting the moving direction of the film on the projection plane of the projection device, and the photodiodes. a device for converting the signals obtained from the array into video signals, three image sensor elements for each scanning point of the photodiode array for electronically scanning the film; arranged such that these image sensor elements are in turn configured to be sensitive to red, green, and blue, respectively, each image sensor element electronically scanning a film connected to a register device for display on a television receiver. In the film image conversion device, the photodiode array is constituted by a charge coupled device (CCD), the register device is constituted by one analog shift register 16, and each image sensor element of the charge coupled device is connected via a storage capacitor. connected to said analog shift register 16 so that the time-series red, green and blue color scanning signals are transferred in parallel onto the analog shift register 16, and the red, green and blue color scanning signals, respectively, are transferred to the output of said register device. A film image conversion apparatus characterized in that output switching circuits 18 and 19 for generating color signals are connected. 2. The film image conversion device according to claim 1, wherein the image sensor elements of the photodiode arrays 14, 20 are formed by alternately and successively depositing different interference layers. 3. Film image conversion according to claim 1, in which the image sensor elements of the photodiode arrays 14 and 20 are constructed so as to be sensitive to red, green, and blue by coating them with strip-like filters. Device. 4. A utility model registration according to any one of claims 1 to 3, in which transfer gates 15, 21 are provided between photodiode arrays 14, 20 and register devices 16, 22, 23, 24. film image conversion device. 5. The projection device has a vibrating mirror system 2, and the projected image of the film image is vertically deflected by the vibrating mirror system at a predetermined frequency necessary for television reception, taking into consideration the film movement speed.Registration of a utility model. A film image conversion apparatus according to any one of claims 1 to 4. 6. The film image conversion device according to claim 5, wherein the amount of movement of the vibrating mirror corresponds to 2/3 of the height of the film image. 7. The film image conversion apparatus according to claim 5 or 6, wherein the vibrating mirror system 2 includes a vibrator S used in a galvanometer. 8. The film image conversion apparatus according to claim 7, wherein the vibrator S of the vibrating mirror system 2 is controlled via an addition logic circuit 5 and an amplifier 6. 9 a first pulse generator 10 which is controlled by sawtooth generator 101 and provides short return motion acceleration pulses during the return step of the sawtooth voltage;
2 and a second pulse generator 103 which is also controlled by the sawtooth generator 101 and supplies short braking and acceleration pulses, the sum of the pulse durations of both pulses being equal to the vertical The retrace time is not exceeded, and the addition logic circuit 104 is further provided with adjusting devices 105, 106, 107, whereby the sawtooth voltage and the amplitude of both pulses are adjusted independently of each other. 2. The film image conversion device described in 2. 10. The film image conversion apparatus according to claim 9, wherein the total pulse period of both pulses of the pulse generators 102 and 103 does not exceed 1.2 msec. 11 First pulse generator 10 for accelerating the return movement
2 consists of a monostable multivibrator, and the second pulse generator 3, which applies braking to accelerate the scanning motion, consists of two monostable multivibrators, and furthermore, the temporal position and duration of the output pulse is controlled by two potentiometers. The film image conversion apparatus according to claim 9 or 10, which can be adjusted independently of each other using the following.