JPH0515099B2 - - Google Patents

Description

[Detailed Description of the Invention] (Field of Industrial Application) This invention is a color FOT (Fiber Optical
This invention relates to a scanning exposure method for tubes.

(Technical background of the invention and its problems) Figures 1 and 2 A and B show an example of color FOT1 used in this invention.
has a nearly rectangular shape with a flat configuration on its front surface.
It is equipped with FOP (Fiber Optical Plata) 2.
A phosphor screen 5 having a plurality of luminescent colors is layered on the inner surface of the FOP 2 (electron gun 3 side), and this phosphor screen 5 has a luminescent characteristic of red R, for example, as shown in FIG. 2B. and phosphor 5G, which has green G emission characteristics.
and a phosphor 5B having blue B emission characteristics are coated in a strip shape, and these phosphors 5
Information on each color emitted from R to 5B passes through FOP2,
A recording photosensitive material 6 that is in close contact with the front surface and moves upward, for example, is exposed to color light.

Figure 3 shows the above-mentioned FOT1 driving method using a raster scan type display color image signal.
It is shown in correspondence with PS. The electron beam 4 from the electron gun 3 is scanned across the red phosphor 5R, green phosphor 5G, and blue phosphor 5B formed in a band shape on the back surface of the FOP 2 in synchronization with the deflection signal of the input image signal. This phosphor screen 5
When passing through, the color image signals SR to SB corresponding to the phosphors 5R to 5B of each emission color are selected, and brightness modulation is performed using the selected image color signals PS. That is, during the time period t0 to t1 during which the electron beam 4 scans the red phosphor 5R, the red component image signal SR is selected and modulated into an electron beam current, causing the red phosphor 5R to emit light, thereby exposing the photosensitive material 6. Ru. Thereafter, in the same manner, the green light emitter 5G and the blue light emitter 5
Time t1 to t2 and t2 to when the electron beam 4 scans B
At t3, the green component image signal SG and the blue component image signal SB are selected to modulate the brightness of the electron beam current. As a result, image signals SR to SG to SB are recorded on the photosensitive material 6 in chronological order. In this way, the image color signal PS indicates the image signals SR to SB that are selectively combined in synchronization with the scanning position of the electron beam 4, and brightness modulation in the FOT 1 is realized by this image color signal PS.

Next, the principle of color recording using the above-mentioned FOT1 will be explained with reference to the drawings of FIGS. 4 to 6.

FIG. 4 shows a raster scan type still color image 10A displayed on a color CRT. A rectangular part 10B of this still color image 10A is sampled according to the raster scan type, and
It is displayed on FOP2 of FOT1 as shown in FIG.
The displayed image on this FOP2 is color-coded into three bands of red, blue, and green, and its brightness is modulated by image signals (SR to SB) of separated colors corresponding to the respective phosphors 5R, 5G, and 5B. ing. Furthermore, the color still image 10A is a red phosphor 5R, a green phosphor 5G, and a blue phosphor 5B formed in a band shape on the FOP2.
A part of the still image 10B is displayed on the screen while shifting the required pixels in a fixed direction 11 like an electronic bulletin board. So, like this, FOP of FOT1
For example, as shown in FIG.
The photosensitive material 6 is brought into close contact with the front surface of the photosensitive material 2, and is exposed to the photosensitive material 6 while being moved in a predetermined direction 11 at the same speed as the movement of the displayed image. Therefore, for example, when the brightness-modulated electron beam 4 traverses the red phosphor 5R, only the red information of the input image signal is recorded as a latent image on the photosensitive material 6. Similarly,
The color photosensitive material 6 is exposed to green and blue image information in color-coded strips, and by moving the photosensitive material 6 in synchronization with the displayed image and overlapping recording, one complete sheet of the photosensitive material 6 is formed. The colored latent image is then exposed.

Incidentally, the sensitivity characteristics of the FOT 1 and the photosensitive material 6 vary depending on each color, and there is a problem in that high-quality image output cannot be obtained if each color is exposed in the same way.

(Object of the Invention) This invention was made in view of the above circumstances, and it is an object of the present invention to provide a color FOT scanning system that efficiently compensates for the difference in sensitivity between RGB of phosphors and photosensitive materials. The purpose is to provide an exposure method.

(Structure of the Invention) The present invention relates to a color FOT scanning exposure method, which uses a single electron gun type color FOT having a screen on which a plurality of phosphors emitting different colors of light are coated in strips. When performing color exposure on a photosensitive material, a scanning electron beam is vertically deflected in the short side direction of the plurality of phosphors, and horizontally deflected in the long side direction, and the scanning time of the vertical deflection is set such that the scanning electron beam is The present invention is characterized in that it is controlled in accordance with the characteristics and the sensitivity of each color of the photosensitive recording material.

(Embodiment of the Invention) In this invention, as shown in FIG.
The entire screen is scanned by vertically scanning 0B in the vertical direction V as scanning lines SC1→SC2→SC3, and by advancing the scanning lines in the horizontal direction H with blanking BL.

Here, in this invention, as shown in FIG. 8, the length x1 of each phosphor 20R to 20B is
At ~t12, the beam is divided and deflected in the horizontal direction H, and the horizontal deflection is discontinuously stepped. That is, from time t0 to t1, for example, RGB scanning is performed using the scanning line SC1 in FIG. 7, and at time t1 to t2 after horizontal deflection, the scanning line in FIG.
SC2 performs RGB scanning, and sequentially from time t2 to
At t3, t3 to t4, ..., the horizontal portion of the horizontal deflection signal, that is, the time when horizontal deflection is not performed, the scanning line SC3,
Vertical deflection of SC4, . . . is performed.
Then, in the blanking BL of FIG. 7, the step of the horizontal deflection signal is increased to deflect it in the horizontal direction H, but in this invention, in particular, the phosphor 2
The deflection speed of the electron beam 4 is made small at both ends of 0R to 20B. This is because, as is clear from the structural diagram in Figure 1, FOP2 of FOT1 is a band-shaped flat plate, and when the electron beam 4 is deflected horizontally at a constant velocity, the electron beam 4 is deflected at both ends of FOP2. This is because the speed becomes faster and becomes slower in the center, making it impossible to accurately reproduce the image on the FOP2. Therefore, by slowing the deflection speed of the electron beam 4 at both ends of the FOP 2 and making it relatively faster at the center, the displayed image on the FOP 2 is always horizontally deflected at the same speed.

In this invention, the vertical RGB scanning time, that is, the emission time is changed for each color, and the emission time for red and green, to which the sensitivity of the photosensitive material is relatively low, is increased, and the sensitivity of the photosensitive material is increased. The light emitting time for relatively good blue color is relatively short. In this way, in the vertical direction
Since RGB scanning is performed in a straight line and the emission time is changed depending on the color, when the output image of FOT 1 is recorded on the photosensitive material 6 that is in close contact with the surface, the photosensitive material 6 will have an accurate image. will be output. In other words, since it is performed perpendicularly for one RGB scanning line, one pixel is
Even if the colors are separated into RGB and deflected, the photosensitive material 6 will not be exposed to light that is shifted in the horizontal direction. Also,
Since the emission time is varied by the phosphors 20R to 20B, the amount of brightness can be adjusted according to the sensitivity of the photosensitive material 6, and each color can be exposed under the same conditions. In this case, it is possible to make the emission time the same for each color and control the luminance signal level, but considering the variation in sensitivity characteristics, it is possible to control the luminance signal level.
A range of 10 ³ to 10 ⁵ must be prepared, which increases the burden on hardware. Therefore, depending on the case, both the light emission time and the brightness signal level may be controlled.

FIG. 9 is a diagram showing an example of a device for realizing the method of this invention, in which a vertical deflection signal is used to determine the position of the phosphors 20R to 20B where the electron beam 4 should emit light.
VD passes through switch 23 to deflection plate 2 of FOT21.
1A and the horizontal deflection signal HD is also FOT
The voltage is applied to the deflection plate 21A of No. 21. and,
Image signal decomposed into RGB, i.e. luminance signal
The BS is input to the gate 25 via the switch 24,
A blank signal BL for commanding blanking is also input to the gate 25, and a brightness signal from the gate 25 is input to the gate 25.
PS is applied to the cathode 21B of the FOT 21. In addition, there is a photosensitive material 22 on the front side of the FOT21.
are brought into close contact with each other and transported, for example, in the direction shown. Note that the switches 23 and 24 are designed to be switched in conjunction with each other. For example, when the vertical deflection signal VD is connected to contact a and scanning the red phosphor 20R, the brightness signal BS
A red luminance signal is also input through the contact a, and is applied to the cathode 21B through the gate 25 as the luminance signal P at this time. The same holds true for contacts b and c.

With this configuration, for example, the seventh
When the phosphor 20R is designated by the switch 23 in the scanning line SC1 in the figure, the red signal of the brightness signal BS is input to the gate 25 via the contact a of the switch 24, but in this case, the blank Since signal BL is not input, gate 2
From 5 onwards, the red luminance signal BS is used as the image signal PS.
It is applied to the cathode 21B of FOT21. In this case, since the horizontal deflection signal HD also has the horizontal characteristic part shown in FIG. 8, the scanning line SC1 is not deflected in the horizontal direction H, and the switches 23 and 2 are
Light is emitted only during the time when 4 is connected to contact a. Then, when the switches 23 and 24 are successively switched to the b contact, the vertical deflection signal VD
The deflection position is input to the deflection plate 21A as the green phosphor 20G, and the brightness signal BS is also applied to the cathode 21B as the image signal PS through the contact b. As a result, the phosphor 20G of the FOT 21 emits light in response to the green luminance signal BS. In this case as well, the phosphor 20
G will be emitted. Blue phosphor 20B
The same goes for
5, the application of the image signal PS to the cathode 21B is cut off, and the horizontal deflection signal HD is scanned to the scanning line SC2 position shown in FIG. 7 by applying the step voltage shown in FIG. 8 to the deflection plate 21A. The line is horizontally deflected. Similarly, the phosphors 20R to 20B sequentially emit light on the scanning line SC2, and the same scanning is repeated to scan the entire phosphors 20R to 20B.

Figure 10 shows a more detailed example of the circuit configuration of this invention, in which image information PI decomposed into RGB
is converted into a digital quantity by an AD converter 31 via a multiplexer 30, and then sent to a buffer memory 32.
The buffer memory 32 stores, for example, frame information for one screen or line information for one scanning line. The timing generation circuit 33 outputs a color control signal CD for outputting the stored RGB image signals, a blank signal BLC for instructing blanking, and a pixel clock PCK.
The pixel clock PCK is output by an address generation circuit 34 to output a pixel address PA for accessing the buffer memory 32, a lookup table 40 storing vertical deflection signals, and a lookup table 41 storing horizontal deflection signals. accessed from buffer memory 32.
RGB image information passes through multiplexer 35
It is converted into an analog quantity PID by the DA converter 42 and then inputted to the gate 46. Further, the RGB position information accessed from the lookup table 40 is sent to the DA converter 43 via the multiplexer 36.
It is converted into an analog quantity VID by the amplifier 45 and sent to the deflection plate 21A of the FOT 21 as a vertical deflection signal VD.
The horizontal deflection signal HI applied to and accessed from the lookup table 41 is converted into an analog quantity HID by the DA converter 44, and then passed through the amplifier 47 to the deflection plate 2 of the FOT 21 as a horizontal deflection signal HD.
1A is applied. The lookup table 40 stores positional information as shown in FIGS. The horizontal deflection signal shown in the step characteristic shown in the figure is stored as a digital value. In addition, the output of the gate 46 is the luminance signal PS
is applied to the cathode of FOT21.

In such a configuration, the image information PI is decomposed into RGB for each pixel, passed through the multiplexer 30 in a predetermined order, converted into digital values by the AD converter 31, and then stored in the buffer memory 32. After all information has been stored in the buffer memory 32, the timing generation circuit 33 outputs a color control signal CD controlled by the RGB luminance time as shown in FIG. 32
The signals are read out for each RGB from the lookup table 40 and transmitted to DA converters 42 and 43 for conversion into analog quantities.
Here, the timing generation circuit 33 outputs the pixel clock PCK in response to the color control signal CD, so that the address generation circuit 34 generates the pixel address.
A PA is generated to synchronize the buffer memory 32, lookup table 40, and lookup table 41. That is, when the image information R is accessed from the buffer memory 32, the lookup table 40 must also output the position signal R corresponding to the red information, and the lookup table 41 outputs the position signal R corresponding to the order of access. The level signal is output according to the characteristics shown in FIG. In this way, the image information accessed from the buffer memory 31 passes through the multiplexer 35 for each RGB, is converted into an analog quantity PID by the DA converter 42, and is converted into an analog quantity PID by the gate 46.
, and if the blank signal BLC is not output from the timing generation circuit 33, it is directly sent to the cathode 21B of the FOT 21 as the image signal PS.
Therefore, image scanning as shown in FIG. 7 can be performed. That is, from the lookup table 40, the RGB phosphors 20R to 2
A position signal corresponding to the position of 0B is accessed, passed through the multiplexer 36, converted into an analog quantity VID by the DA converter 43, and applied to the deflection plate 21A via the amplifier 45. Since the signal HI is also converted into an analog quantity HID by the DA converter 44 and applied to the deflection plate 21A via the amplifier 47,
Image scanning as shown in FIG. 7 can be performed.

On the other hand, FIG. 11 shows an example in which the lookup table 40 or 41 is configured with a RAM 50.
Necessary information is written via the data bus DB from the CPU, and the write address of the RAM 50 is written via the address bus AB and address circuit 52 from the CPU, or the pixel address from the scanning device. Address circuit 52 by PA
Information from the CPU is written to a predetermined address via the CPU, and the write mode is switched by a mode switching signal MS. and,
Reading of data from the RAM 50 is also performed by the address bus AB from the CPU or the pixel address PA from the scanning device, and the accessed information is converted into a digital quantity by the DA converter 53 via the bidirectional buffer 51. It will then be output.

Also, Figure 12 shows the lookup table.
This shows an example configured with ROM, and in this example, information is written in advance to three ROMs 60 to 62.
Data stored in the ROMs 60 to 62 is read out via a switching circuit 63, and the read data is converted into an analog quantity by a converter 64 and output. By preparing a lookup table configured with RAM or ROM in this way, it is possible to store vertical and horizontal deflection signals as digital values, and when the lookup table is configured with RAM, It is possible to rewrite the information arbitrarily, and even when configured with ROM, by writing information to multiple ROMs and allowing selection, it is possible to freely select and use the table. becomes.

(Effects of the Invention) As described above, according to the scanning exposure method of the present invention, the light emission time for each color phosphor is controlled according to the characteristics of the FOT phosphor and the sensitivity of the recording photosensitive material. Images can be created with high quality. Further, in the above-described embodiment, the light emission time is controlled according to each color, but it is also possible to control the luminance amount in addition to the light emission time.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing a schematic configuration of the FOT used in this invention, FIGS. 2A and B are front and side views of the FOP, FIG. 3 is a diagram for explaining an example of the operation of the FOT, and FIG. 6 to 6 are diagrams for explaining the scanning state of the FOT, FIGS. 7 and 8 are diagrams for explaining the principle of the scanning exposure method of the present invention, and FIGS. 9 and 10, respectively. 11 and 12 are block diagrams each showing an example of the structure of a lookup table used in the present invention. 1, 21...FOT, 2...FOP, 3...electron gun, 4...electron gun, 5...phosphor screen, 5
R, 5G, 5B...phosphor, 6,22...photosensitive material, 30,35,36...multiplexer, 32
... Buffer memory, 31 ... AD converter, 42
~44,53,64...DA converter, 40,41
...Luckup table, 50...RAM, 6
0-62...ROM.

Claims (1)

[Scope of Claims] 1. When performing color exposure on a photosensitive recording material using a single electron gun type color FOT having a screen on which a plurality of phosphors emitting different colors of light are coated in strips, The electron beam is vertically deflected in the short side direction of the plurality of phosphors and horizontally deflected in the long side direction, and the scanning time of the vertical deflection is determined based on the characteristics of each of the phosphors and the sensitivity of each color of the recording photosensitive material. 1. A color FOT scanning exposure method, characterized in that each phosphor is controlled individually according to the color FOT. 2. The color FOT scanning exposure method according to claim 1, wherein the control includes brightness control according to the sensitivity of each color of each of the phosphors and the recording photosensitive material.