JPS5828116B2 - Cathode ray display tube display position control method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a phototypesetting machine or the like that projects and prints characters, numbers, symbols, etc. (hereinafter referred to as characters) displayed on a cathode ray display tube (hereinafter referred to as CRT) onto a photosensitive material. Regarding a CRT display position control method for a device in which the CRT itself is moved in order to print over a wider area than the tube surface, it is particularly concerned with controlling the character printing position on the sensitive material and the position of the CRT relative to the sensitive material. After setting the difference △1 from the relative current position in a counter, the counter is incremented by a CRT movement detection pulse, and when the counter value is less than a predetermined value, the CRT deflection circuit uses the placement as a display position signal. By supplying the CRT to the CRT, it is possible to simultaneously perform projection printing of characters even while the CRT is moving, thereby enabling continuous printing without providing a printing prohibition time such as a stabilization time required for moving and stopping the CRT. At the same time, when multiple characters can be displayed on a CRT, printing speed can be improved by constantly updating new characters as objects for projection printing without having to wait for the display of the last character to finish. It is something that

Conventionally, a projection exposure apparatus (or phototypesetting machine) that prints over a wider area than the CRT tube surface, as described above, has been used.
For example, British Patent No. 1390770, JP-A-52-29730, or JP-A-5
Those described in JP 0-39424 and the like are known.

These conventional devices aim to expand the area in which projection printing can be performed by moving the CRT parallel to the photosensitive material, but in all of them the CRT stops while characters are being projected printed, which is a problem in terms of printing speed. From this point of view, it had the following problems.

That is, during the period when characters are displayed on the CRT, the CRT
When printing is performed by stopping the CRT and moving the CRT to the next printing position when printing is completed, the stabilization time of the mechanical system required for moving and stopping the CRT becomes the printing prohibition time.

Furthermore, even if a plurality of characters 2 can be displayed on the CRTl and the plurality of characters can be printed at corresponding positions on the photosensitive material as shown in FIG. 1, the last character will finish printing. The CRT cannot be moved to the next step (for example, until all 42 characters of 9 characters shown by the solid line in Figure 2 have been printed), and this is a factor that hinders the improvement of printing speed. Ta.

However, if it becomes possible to print while moving the CRT, not only will the above-mentioned moving time and stabilization time be automatically eliminated, but also, as shown in Figure 2, after the characters A88B and C are printed, the next CR while displaying another character 2
By moving TI to the dotted line position 3, you can newly add the characters H, H, and G to the character selection operation as printable characters, so the average selection time per character can be reduced accordingly. .

In view of the above points, the present invention provides a display position correction method to enable printing even while the CRT is moving, and the details thereof will be explained below.

FIG. 3 is a diagram showing an embodiment of a circuit configuration that realizes the method of the present invention, in which 4 and 5 are horizontal deflections that generate a signal to perform raster scanning 6 for one character on the CRTr. and a vertical deflection signal generating circuit which outputs a predetermined sawtooth signal in response to a command from the CPU 7, and the characters displayed on the CRTl by the raster scan 6 are printed on the photosensitive material 9 via the optical system 8.

Reference numeral 10 denotes an encoder that generates pulses as the CRTl moves relative to the photosensitive material 9 (in the illustrated case, moves in the Y direction as indicated by an arrow 11), and 12 indicates the current position P of the CRTl in response to the output pulses of the encoder 10. This is a current position counter indicating the current position.

13 and 14 are input devices 15 such as tape readers, etc.
said C based on a command signal supplied from the outside via
The printing position of each character on the photosensitive material calculated by PU7,
This is a counter in which a difference Δ from the current position P indicated by the current position counter 12 is set, and in the illustrated case, the difference in the X direction is stored in the counter 13, and the difference in the Y direction is stored in the counter 1.
4, respectively, and the counter 14 is incremented by the output pulse of the encoder 10.

The outputs of these counters 13 and 14 are supplied to adder circuits 20 and 21, respectively, via D/A converters 16 and 17 and magnification conversion circuits 18 and 19, which will be described later. ) and vertical (Y direction) deflection circuits 22 and 23, respectively.

Therefore, a predetermined raster scan is performed on the CRTl with reference to the positions corresponding to the output values of the counters 13 and 14.

Further, 24 is an area determining circuit which will be described later, and 25 is an AND gate.

FIG. 4 shows CRTl, photosensitive material 9, or the value P.

This is a diagram schematically showing the relationship between L, Δ, etc., and ±N is for CRT.
The width of the printable range is indicated by l, and the point Q is the printing position of any desired character on the photosensitive material.

As is clear from FIG. 4, △□ on the photosensitive material and the corresponding mo on the CRT are ml
Since the relationship is -Δ1/M, the value Δ1 set in the counters 13 and 14 is multiplied by 17M by the magnification conversion circuits 18 and 19 and then supplied to each deflection circuit.

FIG. 5 is a diagram showing in detail the configuration of the correction circuit 26 shown in FIG. 3.

In this FIG. 5, each counter 14-1 to 14-n is
The value Δ1 corresponding to each character printed at a different position on the photosensitive material is set by the CPU 7, and is increased or decreased by a value corresponding to the amount of movement of the CRTI by the output pulse of the encoder 10. In the figure, only dl is C
When RTl moves and reaches point R, the value of the counter becomes △
22Δ1-d.

The area determining circuit 24 determines whether or not the value △ of each counter is within the width ±N, so that the position on the photosensitive material 9 corresponding to the value of the counter falls within the range that can be printed by the CRTl. This is a circuit for identifying whether or not the current is present, and outputs a signal when -N<Δ<+H.

Therefore, through the AND gate 25, the D/A converter 1
The signal value input to 7 indicates a position that can be displayed by CRT1.

Since the within-area determination circuit 24 is provided in this way, the value commanded from the CPU 7 to the counter 14 is CR at the time of command, such as the value △2 corresponding to point S in FIG.
There is no problem even if the value is at a position that cannot be printed with Tl, and in this case, CRTl should be moved by, for example, d2 and
When △3-d2+H, the area determining circuit 24 detects that printing is possible.

Then, when a print start signal is input from the terminal 27, the counter 1 for printable characters is counted as described above.
The values of 3 and 14 are inputted to the deflection circuits 22 and 23 via the magnification exchange circuits 18 and 19 to determine the display position reference, and furthermore, the raster signals of the deflection signal generation circuits 4 and 5 are superimposed to form 1. Raster scanning for characters is performed.

If the CRTl moves to point R during the above display (printing) operation, the value of the counter 14 changes from △1 to △2 as described above, so the CRTl
The upper display position will also be moved to a position corresponding to m2, which is 1/M times Δ2.

However, the printing position on the photosensitive material 9 corresponding to this new display position is determined by the optical system 8 by multiplying the m2 by M, that is, an amount corresponding to △2, at the new position R of the CRTI. Therefore, as is clear from Figure 4, the printing position standard itself based on the value of counter 4 is always stopped at point Q, and is not affected by the movement of the CRTl at all. It's going to happen.

Therefore, if it is done as explained above, even if the CR 81 is moved during projection printing of any one character, the character image projected onto the photosensitive material 9 will not move at all and the desired printing can be performed. It's going to happen.

As described above in detail, the method of the present invention is to set the difference △1 between the externally commanded character printing position on the photosensitive material and the relative current position of the CRT with respect to the photosensitive material in a counter. , the counter is incremented by a CRT movement detection pulse, and when the counter value is less than a predetermined value, the mounting position is supplied as a display position signal to the deflection circuit of the CRT, This allows CRT
This makes it possible to print while moving the CRT, making it possible to print continuously without setting up printing prohibition times such as the movement time of the CRT or the stabilization time required for stopping.
When a plurality of characters can be displayed on the screen, the printing speed is improved by always updating new characters as objects of character selection operation.

For convenience, the above explanation has been about the case where the CRTl is moved in the vertical deflection direction of the raster scan 6, but this method is also applicable to the case where the CRTl is moved in the horizontal deflection direction.

Of course, in this case, the correction circuit 26 must be provided on the horizontal deflection circuit 22 side, but if correction circuits 26 are provided both horizontally and vertically, the CRTl can be moved freely within the XY plane. It is possible.

Furthermore, it goes without saying that the specific circuit configuration for realizing the method of the present invention is not limited to the one described above, and that various configurations can be used.

[Brief explanation of the drawing]

1 and 2 are diagrams illustrating a conventional display example of a cathode ray display tube and a display example made possible by the method of the present invention, respectively, FIG. 3 is a diagram showing one circuit side that realizes the method of the present invention, and FIG. The figure shows the relationship between the display position on the cathode ray display tube and the print position on the photosensitive material. Figure 5 shows the correction circuit 26 of Figure 3.
FIG. 1... Cathode ray display tube (CRT), 4, 5...
...Raster deflection signal generation circuit, 7...CP
U, 9...Sensitive material, 10...Encoder, 12...Current position counter, 13, 14...
...Counter, 15...Input device, 18,
19... Magnification conversion circuit, 24... Area determination circuit, 26... Correction circuit.

Claims (1)

[Claims] 1. When printing a character image reproduced on a movable cathode ray display tube on a sensitive material, the difference Δ1 between the character printing position on the sensitive material and the current position P of the cathode ray display tube with respect to the sensitive material is calculated. After setting the counter, the counter is incremented by a cathode ray display tube movement detection pulse, and when the value of the counter is below a predetermined value, the position is supplied as a display position signal to the deflection circuit of the cathode ray display tube. A method for controlling the display position of a cathode ray display tube, characterized in that it is possible to print characters by continuously moving the cathode ray display tube while displaying a character image on the cathode ray display tube.