JPS5931941A - Exposure controlling method of imaging camera - Google Patents

Abstract

PURPOSE:To set exposure time properly by generating a signal for specifying a photometric area with delay corresponding to the time of arrival at the photometric area in response to a horizontal and a vertical synchronizing signal, and measuring variation in the brightness of the area automatically. CONSTITUTION:A composite synchronizing signal from a CRT display device 1 is separated into the horizontal and vertical synchronizing signals, which are inputted to monostable multivibrators MH1 and MV1 and further MH2 and MV2 to generate pulses for specifying the horizontal and vertical addresses of the photometric area. A sampling signal Samp and a nonsampling signal Samp' are generated by pulses from the MH2 and MV2. A signal from a photodetecting element 18 is ampled by the signal Samp. Once a shutter is released with an exposure button, a switch S3 is opened and an integrator I1 integrates the sampled signal and also counts a clock signal. When its integral output exceeds a reference value, a comparing circuit CP1 generates a high level and the current counted value Cl is stored. A controller closes the switch S3 and calculates a proper exposure counted value C2 by using a value C1 to close the shutter at the time of the value C2.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides an imaging camera with an exposure side σ(
1. Regarding method.

In recent years, CT (Computed'
ronOgrrrtphy) device, US (Ult
RA 5ound) equipment, etc. are being rapidly purchased. These devices display the affected area on a cathode ray 'a display,
Moreover, it is in the form of a hard copy.

In general, the brightness of the image displayed on this cathode ray tube display device fluctuates due to time fluctuations in the performance of the cathode ray tube (CRT), variations in the CRT, fluctuations in the pressure applied to the CRT, etc.
Causes a change in contrast. Therefore, the IQ base control (burning is controlled at 117J) that prints the CRT image to 1f + i becomes impossible to maintain proper exposure at all times, and the hard copy is Because it causes trouble when taking the above-mentioned f,! There is a strong need for the development of a technical means that can automatically catch JJJ and eliminate its fluctuations based on it.

The present invention (・↓This invention was devised by focusing on the drawbacks of the conventional techniques as described above, and its purpose is to automatically catch the brightness fluctuations of the displayed image (2. Expose the above image to a photosensitive material) An object of the present invention is to provide an exposure control method for an imaging camera that can appropriately set the exposure time.

This purpose is achieved by measuring the brightness of the photometric area of one image display. In response to the water signal and vertical synchronization signal provided for the purpose, there was a delay of the amount of time it would take to reach the above-mentioned 6111 optical territory, and the response to issue 18 was delayed. This is achieved by measuring the brightness of the photometric area.

The present invention will now be described in detail with reference to the accompanying drawings.

FIG. 1 shows a Zannoring signal generation circuit A of the apparatus of the present invention. In this figure, l is an image display device that displays an image including the tα region for dimming in raster format, and this is, for example, a CRT display device. It is. This device displays a CT-equipped image, and the imaging device of the CT device 1 is constructed so that the image is projected onto a photosensitive system through a shutter (the shutter and photosensitive system are not shown). The device i is connected to the sync separator circuit 6 via line 2, switch 3 and lines 4 and 5. The horizontal sync signal outputs 6) and 6V of circuit 6 are connected to the corresponding lines 7, 6 and 6, respectively. 8, and the interlocking switch -9 is a prerequisite! 10. connected to tx. When the contact E'r it is switched to the contact 9-2, the output is shifted by -1'. Also, by changing the switch 9 to the contact 9-1, IrJ is set in advance in the device 1.
The horizontal synchronization (N and vertical synchronization 4f outputs 12 and 13 that are output by switching the switch 9 to the 03 wire 1
Connected to 0,11.

Line 10 is connected to one input of AND circuit 14 via mono multivibrator MIII and Mn2, and +v! !
It is connected to the other human power of the AND circuit 14 via the 11fi mono multi-high break Mv1 and MV2. A sampling signal Samp is generated at the output of the AND circuit 14, and a non-sampling signal Samp is generated at the output of the inverting circuit 15 connected to the output of the circuit 14. Monomultipipe lake M 111, Ml (2, MVI, and M
The output of the oscillator 16 is connected to all iLKs of v2. As shown in FIG. 2, the monomultivibrator may be configured such that its metastable time is determined by the time constants of its own time constant circuits R and C, or
Also, as shown in figure ff13, 7 lip-flop circuits 1
6 and a presettable counter are also good. In the latter case, #lO or 1 to C human power of circuit 16
1 is connected, and the counter 17Ki. L that human power'17a
A preset switch 17d is provided to determine how many clock pulses must be input to the clock input 17c to generate a low level signal at the output 17b from when a high level signal is input to the output 17b. It will be done.

Figure m4 shows a sample value integrating circuit B connected to the light receiving element 18. The light-receiving element 18 is arranged to receive light from a photometric area displayed at a constant brightness such as symbols, characters, etc. displayed on the above-mentioned CRT.
An eighth amplifier AAI is connected, and its output is connected to one input of an operational amplifier 20 constituting the integrator 1 through a switch S1 whose opening and closing are controlled by the sampling signal Samp, and the other input of an operational amplifier 11v4 amplifier 20. is connected to ground, and an integrating capacitor 21 and a switch S3 are connected in parallel between the output 21' of the operational amplifier 20 and one input. The switch 83 determines the point in time when the integral function is generated, and is controlled to open and close by a control device (p1, which will be described later). A switch S2 whose opening/closing is controlled by a non-zangling signal Samp is interposed between the output of the switch S1 and the ground.

Figure 5 ← [Output 21' of sample value integrator circuit B in Figure 4
3 shows the comparison circuit means C connected to the . The output 21' is connected to one input of the comparison circuit CPI, and the other input of the comparison circuit UPI is connected to the reference value setting circuit VRI.

The output t of the comparator circuit CPI is connected to the control device shown in FIG. 7 via or without the buffer circuit BF1.

The control llk IVt in FIG. 7 is configured as follows.

In this example, the control device is composed of a t microcomputer, with a bus of 3 (1i), a central front A: processing unit head 3], a program memory 32, a random access memory 33, a clock 34, and an input/output An interface 35 is connected to the output interface 35, and a line 36 connecting the switch S3 in FIG.
, connected to the output of the comparator circuit CPI in Figure 5.
7. Line 38 connected to >n light button of photographing device;
940, which is connected to the shutter driver 39 that controls opening and closing of the shutter, and similar lines connected to other photographing devices.

Next, the operation of the apparatus of the present invention having the above configuration will be explained.

When the override video number 1 or missing synchronization signal from the CRT display device 1 causes selective switching of the switch 3 and is supplied to the synchronization separation circuit 6, the output 611 is e.
, 6V from the horizontal sync signal 1a, the vertical sync signal is generated and sent out onto the lines io, it through the switch 9 which is switched to the contact 9-2 side. If a synchronization signal is generated at the output 12.13 of the CRT display N1, it is sent onto the terminal 1.0.11 via the switch 9 which is switched to the contact 9-1.

The waveforms 19.1 of these signals are (6-1) and (
6-2), (6-1) is the horizontal synchronization signal,
(6-2) is the J-J cut signal.

From the mono multi-bi break M H1 that receives the horizontal synchronizing signal on the top 10, as shown in (6-3) in FIG. The mono-multivibrator M I-12 which receives this pulse is generated from the end of the pulse at t2.
A pulse (see (6-5) # in FIG. 6) is generated that lasts for a time of 1. Regarding these two pulses on the screen of 01ζT, they are used to determine the horizontal address of the photometric area displayed by Terunari Ichiya (threshold Me) of symbols, characters, etc. shown on the screen. It is something.

Also, as shown in (6-4) in Fig. 6, a mono multivibrator MVI receiving the vertical interval Jυ signal on the line 11 generates a pulse that lasts for a time t3 from the end of the vertical synchronizing signal, and this pulse The mono-multivibrator MV2 receives a pulse (see (6-61 in FIG.
Live one life. Regarding these two pulses on the CRT screen, they are used to determine the vertical address of the above-mentioned photometry area.

Mono multi-by-break M112, AND circuit 14 from the pulse from MV2 and Zan 1 Nongui word 5ar
Generate np. Further, the inverting circuit 15 generates a non-ring ring signal +3Salf.

In this way, the Langlin buoy [J Sa
mp increases 4~' from the light receiving element 18, 8 units AAI
The amplified signal is sampled (at this time switch 8
2 has been opened].

This sample (number m) is not integrated by the integrator 11 (normally, the switch S3 is closed) unless the operator presses the exposure button for photographing.

When the image displayed on the CT device is exactly what you want to shoot, the operator presses the exposure button ((8-1 in Figure 8).
1), and this is notified to the central processing unit 31 via the human output lanter face 35 in FIG. Turn on the camera and open the sea vine of the camera (see (8-2 in Figure 8)).
)) At the same time, the opening of the sous f-tuna S3 (see 9 in Fig. 4) is caused (see (8-3) in Fig. 8).

It was sampled by this coil "Zeng 111N! ,'+A
The output It<"E of A1 is integrated by the Ali divider 1, and from the start of this integration, the central processing unit a31 counts the clock g from the clock 34.

- On the other hand, the output of the integrator 4 (Fi is the comparator circuit Cl)
) To 1 J-) When the current signal is compared to the standard 1 shift and the upstream signal exceeds the standard 11α, the comparator circuit CPI generates a signal at its output (rope level). (See (8-4) in the figure), this signal 113' is sent out on the line 37, and sent through the input/output interface 35 to the central processing unit 31, and in response to this signal, the above-mentioned Karan) 4LI) by? The counted value CI (see (8-5) in the jtT8 figure) is randomly accessed by the -1-item of 33. From the processing equipment 31t, connect the input/output Innoturn upper chair 35 to A:+I to close the switch S3.
is closed (see (8-3) in 8th line 1).

In addition, using the central calculation processing unit baa: 31 and t, 1-1 = the above-mentioned non-uncount value CIC:lζ'1' (a value that reflects the brightness of the display surface), the appropriate exposure power value C2 is set to a constant value of 49. Then, with the above-mentioned counting operation, I mourned the loss of 02.
At the 7th point in time (81 yen 1 + 8-5 n:heteru), the central operation J7-Juri device ID 31 inputs and outputs the LS No. 35 and the shutter driver 39 in the village.
Turn it off and close the C shutter.
I! Ru.

In this way, 'y' becomes 0 when the first side 1 becomes ijJ scold.
Also, in the side tilting device 1, the exposure time is determined from the exposure C cacunto 1, and II! 8 yuan + 41° [((') Corrections for the foul play are still in progress.

Note/(In the Ti example, ←j1.6I) 1 The case where the light area is 812, characters, etc. has been described, but it is also possible to display a wedge in that area. This web'+;L C1-T display section))
Ill be dressed in a striped, step-by-step manner.
The power difference table η is used for the 111 constant of contrast. The above-mentioned MHL, Mn2゜M]I3. Ml14. −=,
MVI, MV2. MV3°MV4, . . . and it is necessary to set respective holding times. , and when using this method, the gamma value of the method can be changed to 'iff JIl!' by 7 f-packing the signal obtained from it to the video signal. You can. Feedback is given to this contradiction so that the comma value of Wesochi does not change. There is also a stand, and there are times when a certain gamma (when adjusting IK) is faster than r5.

As mentioned above, according to the present invention 1/C, the brightness of the side light that can be determined by t is measured and IU is), so Δ positive jealousy Light hours can be established.

(The effect of the ink is relatively simple.) With 4 formations: 4 formations (J
Effects such as 44t are obtained.

[Brief explanation of the drawing]

Figure 1 is a diagram of the °sampling driver signal generation circuit, Figures 2 and 3 are diagrams showing various forms of mono-multi-by-break used in °s < 1 circuits, and Figure 4 is a sample. Figure 5 shows the value integration circuit means, m' 5 shows the comparison circuit means, rr! 6 is a waveform diagram for explaining the operation of the circuit shown in FIG. 1, FIG. 7 is a diagram showing the control 1III device, and FIG. 8 is a diagram of various signal waveforms. In the figure, 8 is a simple log signal generation circuit, B is a sample value integration circuit j'6 means, C is a comparison circuit means, and D is 111J.
This is an elevation device 6. Patent applicant Konishi Rokushahei Kochiku Co., Ltd. Agent Yoshimi Eihara 21 Figure 1 Figure 3 Figure 4 Figure 5

Claims (1)

[Claims] 1) Set d(1(light 1jCt castle) at a proper place on the image display surface, set the brightness of the photometry area !ti11, and
+ I recommend setting the appropriate exposure time according to IJCK.
F? +'&-J imaging camera exposure side (I
j1 method. 2) 2) A (specifying 7) for photometry, which specifies the 101 loss, is used for the rendering system of raster format images. A special control unit characterized in that the signal is generated with a delay of K g from the time it reaches the photometry area, and measures the brightness of the light measurement area in response to the signal. Section 1: Light control method for self-mounted imaging camera. 3) Above image! #An exposure control method for an imaging camera as set forth in the scope of the Patent MN Claim, item 1 or 2, characterized in that a band-shaped portion having a shade difference is displayed as a dl11 light region on the display surface.