JPS6225733A - Electric adjusting circuit for camera - Google Patents

Abstract

PURPOSE:To obtain an adjusting circuit that can make the space of an electric circuit small at low cost by reading digitized correction data from a nonvolatile memory element and executing an arithmetic processing. CONSTITUTION:The digital data of an exposure factor including the luminance information of an object are inputted to an arithmetic unit 11 through a multiplexer 9 and an A/D convertor 10, and digitalized correction data are read from a nonvolatile memory element 20. The memory element 20 can write data from a data line 22 in the memory area in jumped 21 state. In a assembling process, fixed luminance is given to a camera and necessary data are written in the memory element 20 basing on a measured value obtained by a tester in which the deviation from proper exposure value of exposure is corrected. When a jumper 21 is detached after confirming that the written data are correct, it becomes impossible to write data in the memory element 20 thereafter, and unprepared change of data hardly occurs.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an electrical adjustment circuit for a camera, and more particularly to an adjustment means for an electrical circuit of a camera.

[Prior Art] Conventionally, in an electric circuit of a camera. 22, i.e. EE
Adjustments such as level and display level are mainly made using semi-fixed resistors (
The so-called analog quantity was adjusted by using a trimmer resistor (trimmer resistor) or by trimming with a fixed resistor (using a racer etc.).

Next, the adjustment means for the j-1 yen, D-example, will be explained based on the 81st example. First, automatic exposure photography with a camera is performed as follows. That is, the object RB degree information enters the light receiving element 1 through a photographing optical system (not shown), is converted into a photocurrent, and the photocurrent is sent to the operational amplifier 2. From the compression diode 3, the signal is logarithmically compressed by the f5+fpI optical circuit and converted into a voltage value. This voltage is applied to the compensating diode 4. The signal is compensated by 194 degrees and level-adjusted by a semi-fixed resistor 5 for adjusting the level and 22, and a constant current and a thickness 8, and is manually inputted to an A/D converter 10 via an analog multiplexer 9. Further, the A/D conversion circuit 10 receives an aperture information voltage from the multiplexer 9 from the aperture information manual resistor 6, and a film sensitivity information voltage from the film sensitivity setting resistor 7, which are then A/D converted. . and,
The output of the A/D conversion circuit 10 is input to an arithmetic unit 11. The arithmetic unit 11 receives subject brightness information Bv value (apex notation) and aperture information AV, each input as a digital value.
Based on the value (apex notation) and the film attitude information Sv value (apex notation), Nyanota speed information HiTvVi (
Apex notation) is calculated by the well-known calculation formula of Tv-3v+By-Av to obtain the appropriate exposure speed: 1-, and when the aperture is first narrowed down by activation of a release start means (not shown), the aperture is linked to that narrowing down. The arithmetic device 11 counts the pulses HH7 from the contact piece 12 moving by 1G, and when a predetermined value is reached, the switching element 13 is made conductive, and the aperture locking magnet 16 is activated to stop the aperture. Next, after the mirror-up of the movable mirror is completed, the switching element 14 is made conductive to operate the front curtain running magnet 17, and the front curtain is run. After the time determined by the above calculation, the switching cable 15 is turned on to operate the subsequent traveling magnet 18,
The rear curtain is unlocked, the rear curtain is allowed to run, and the shooting is completed.

This is how automatic exposure photography is done.
In this camera, there are variations in the transmittance of the optical system, the efficiency of the light receiving element, the current value of the constant current source 8, the film sensitivity, and the resistance values for setting the aperture. is Bv' −Bv+ΔB
v, A v' - A V +ΔAv,, Sv' -
This includes an error such as 5v+ΔSv.

Therefore, in the conventional case, the semi-fixed resistor 5 is inserted to correct this error. That is, the Bv value is corrected by the correction value ΔCv and A/D converted. In the assembly process, a constant amount of light is applied to the camera, the EE level is inspected, and the semi-fixed resistor 5 is adjusted to compensate for any deviation from the appropriate exposure value. In other words, what the arithmetic device 11 actually calculates is Tv-3v+ΔSV+BV+ΔBv-ΔCv-(Av+ΔAv), which is ΔCv-ΔSv+ΔBv-ΔA
ΔCv will be adjusted so that it meets the relationship of V.

By the way, recently, a small amount of EEPROkl (L]cctr+ has been developed as a non-volatile digital memory element.
callyerasaolc and progr
acable read only
) is being emitted 1X)j. This EEPRO 2.1 is
Nikkei Electronics July 1, 1985 issue P235
``Analog digital l Konju CM OS custom IC
As introduced in the article ``Aiming to reduce costs by integrating EEPROMs into devices'', it has the remarkable effect of being economically advantageous because only the required capacity can be integrated, and can replace DIP switches. It can be used to memorize and calibrate operating procedures for meters, etc. Programs can be stored and updated.

It can be used for a wide range of purposes, from digital circuits to analog circuits, such as for trimming analog circuits.

[Problems to be solved by the invention] As with conventional adjustment means, the method of adjusting a semi-fixed resistor generally requires a human to read the circuit output value with an indicator and adjust the semi-fixed resistor to the target value. This method takes time, is difficult to automate, and reduces both parts costs and assembly man-hours. Also, although trimming using a laser or the like can be automated, the trimming device is large-scale and cannot be readjusted.In other words, it is possible to do it with the electrical components assembled on the board, or if they are assembled into the casing of the camera body. There were problems such as it being impossible.

Therefore, an object of the present invention is to provide an electrical adjustment circuit for a camera that uses the recently developed non-volatile memory element described above to solve the problems of conventional adjustment means, and that can be used at low cost and with a small electrical circuit space. It is on offer.

[Means and operations for solving the problem] The electrical adjustment circuit of the present invention reads digitized correction data from a non-volatile memory element when performing calculations based on digital values, and stores an eL containing the correction data. After calculation processing, the camera's exposure control circuit or exposure display circuit is controlled based on the ER calculation, eliminating the need for analog adjustments. The amount of error from the appropriate value of the control result including various dispersion factors is determined by ilP + and data that should be the appropriate amount is written, or the sequence for measuring the amount of error and writing the correction data is programmed in advance. .

[Example] The present invention will be explained below with reference to illustrated examples.

In addition, in the actual example described below, only the new components will be explained, and the explanation of the parts that are similar to the conventional device configuration already explained with FIG. !Avoid contradicting, just add the sign.

In the present invention, the conventional semi-fixed resistor is removed and the nonvolatile memory element is used.

FIG. 1 shows a first embodiment of the present invention, in which a nonvolatile digital memory (hereinafter simply referred to as a memory element) 20 receives data from a data line 22 with a jumper 21 connected. Can write to memory area. In the assembly process, a constant brightness is applied to the camera, and the necessary data is written using a writing device (not shown) based on the Al constant value, which is measured by a calibrated tester to determine the amount of deviation of the exposure amount from the appropriate exposure value at that time. and write to the memory element 20. If the jumper 21 is removed after confirming that the written data is correct, no data can be written to the memory element 20 from now on, and the data will not change inadvertently.

Furthermore, the data to be written is determined as follows. A
As mentioned above, the data after /D conversion includes errors, so the exposure value will deviate by ΔCv - ΔSv + ΔBv - ΔAv. Therefore, digital data corresponding to ΔCv is written in the memory element 20. Arithmetic device 11
reads data corresponding to ΔCv from the memory element 20 before and after A/D conversion of each data, and calculates Tv=Bv'+SV'=Av'-ΔCv. Then, the obtained Tv value is Tv-Bv+5v-
Av, the error is canceled and an appropriate shutter speed value is found.

It is also possible to separately correct the error ΔAv between the aperture value set by the aperture information input resistor 6 and the actual aperture value. That is, when the actually controlled aperture value deviates from the set aperture value by ΔAv, the number n of pulses generated by the sliding contact piece 12 corresponding to ΔAv is written in the memory element 20, If ΔAy is positive (too much aperture), count the pulses in advance and close the aperture locking magnet 1.
It is sufficient to subtract n from the number of pulses for operating 6, and conversely increase n if ΔAv is negative.

FIG. 2 shows a second embodiment of the present invention, in which the present invention is applied to a film surface reflection 1lpI optical exposure control camera. Prior to exposure, the arithmetic unit 11 first turns on the switch 36 and turns off the switch 37 at the same time. Then, constant current integration is performed by the capacitor 35 of the fundamental voltage integration circuit including the constant current source 28, and the output of the operational amplifier 34 rises as shown by the characteristic line A in FIG. Then, the arithmetic unit 11 turns off the switch 36 after the time To corresponding to the film sensitivity has elapsed.
Finish the integration. Thereafter, the l-value calculating device 11 turns on the switching element 14 and causes the shutter front curtain travel magnet 17 to run with a=a, and the shutter front curtain travels at the same time as p,'
At time t, the switch 32 is turned off a total of j7'C times 711. Therefore, the reflected light from the front Iλ plane and the film plane is aF
Since the light 7 current from the light-receiving element 1 is integrated by the capacitor 31, the output voltage of the operational amplifier 33 rises as shown by the characteristic line B (third diagram jj:j). When the time Ts has elapsed from the time when the characteristic lines A and B intersect, the output of the comparator 38 becomes L (low), the switching cable 39 is turned off, and the rear hook locking magnet 4 is turned off.
The energization to 0 is released and the rear part of Nyanota is locked or released.
< h “The camera moves and the exposure ends.

Note that numerals 41 to 44 indicate electrical contacts for reading film sensitivity information of the cartridge information, so-called Dx coat.

In the exposure control camera configured as described above, electrical exposure adjustment according to the present invention is performed as follows.

That is, a film cartridge with a predetermined film type power information is loaded into the camera, a photographic lens with a constant aperture diameter is attached to the camera, and a predetermined [・1 degree of light] is emitted from the front of this lens. give. When the camera is released and released in this state, the camera performs the operations described above and performs exposure at a certain photographic speed Tsa.

On the other hand, the exposure calculation device 11 contains information on the normalized tar speed Ts that has been standardized in advance, and when there is a jumper 21.22, the above speed Ts and the actual tar speed Ts.
The ratio Ts' of a is calculated, and the value of Ts'-Ts/Tsa is written in the memory child 20.

In this way, during actual exposure, jumper 21.
22 is removed, the arithmetic unit 11 can obtain proper exposure by correcting the integration time To to the capacitor 35 by Ts' times before exposure.

In addition, by setting similar predetermined values for different film sensitivities and removing one of the jumpers 21 and 22 when writing data to the memory element 20, it is possible to set the same predetermined value for different film sensitivities. It is also possible to correct the lower side and the lower side independently. In particular, in non-compression type exposure control circuits, h'3
``Depending on the FJ, the tendency of exposure errors may differ between the low and high film speed ISO sides, so in such cases, it is significant to adjust according to the film speed ISO, which is not possible with semi-fixed resistance adjustment.

What is important in this embodiment is that, as explained in the prior art, a calibrated tester or a lens that generates a predetermined aperture value (fl-ri) and (-li degree generating means or 1-ri,
By using such a spontaneous adjustment program in the calculation device 11, exposure and engineering can be easily adjusted.

Also, in the case of hii iE of the aperture value as described in the first practical example, pulses with a difference from a predetermined number of pulses n for a predetermined brightness are programmed in the arithmetic unit 11, and the jumper 2], 22 can be arbitrarily loaded into the memory element 20.

Test 2: Read the error data orally 1. ) 11] Adjusting the adjustment by moving the fixed resistor i' - ii +] takes a lot of time, and the relationship between the error and the amount of rotation is unclear, so it must be repeated several times, In the present invention, since the error and the amount of correction are uniquely determined, it is only necessary to release the shutter once for each correction.

Furthermore, as described in the first embodiment, it goes without saying that in the storage method, exposure display data (not shown) can also be corrected at the same time.

Next, FIG. 4 shows a third embodiment of the present invention, in which the present invention is applied to an exposure display circuit. In this example as well, as explained above, a predetermined (F degree, a lens with a predetermined aperture diameter, the number of embossed steps, the output that should be obtained with the ISO sensitivity, in this case, a predetermined shutter speed display) is calculated in advance. A memory element 20 stores data that is programmed in the device 11 and corrects the difference between the actual display and the appropriate display by applying a predetermined brightness, a lens with a predetermined aperture diameter, and a film 1 degree Is○ to the camera. After writing and writing, remove the jumper 21. From now on, the arithmetic unit 11 will be able to read data from the memory element 20 in addition to The display element 50 displays the result of reading the Futakiura positive value and performing correction calculations.
to be displayed.

Note that CLK is a clock signal, Data is a serial signal line, EN is an enable signal for accessing the memory element 20, and R/W is for selecting whether to write or read data to the memory element 20. The signals are shown respectively.

Sending and receiving data serially to and from the memory element 20 in this way is very effective because the number of signal lines can be reduced.

In addition to the correction data mentioned above, the memory element 20 also stores data such as the number of film frames set by the switch 53, the operation mode, etc., which is necessary to be stored even when the battery is exhausted or when the battery is removed. Furthermore, the data is sent to the display driver 511 and the display element 52.
displayed externally or in the viewfinder.

5 to 7 show details of the nonvolatile digital memory device 20 used in the present invention.

As shown in the block diagram of FIG. 5, in the memory element 20, a clock signal CLK is input to an address control circuit 61, and chimney control signals EN, R/
From the moment either or both of the W signals turn L (low), the address is incremented or decremented by the clock signal CLK. Serial data input from the Data line in synchronization with the clock signal is
Serial-to-parallel conversion 2: The data is converted into parallel data in 62 and output onto the internal data bus 62a.

The data output onto the internal data bus 62a is further latched into the display data register 63 addressed by the address control circuit 61. When the display data is completed, data such as the number of frames/correction amount/photographing mode are sent, and are also converted into parallel data by the serial-to-parallel converter 62 and output onto the internal data bus 62a. Then, the memory address addressed by the address control circuit 61 is latched into the disk 64.

The writing operation of the communication η ends with -L, or when writing the hli pressure data, the jumper 19. The correction data given by 1 is sent to the Data line. Therefore, similarly, the l+Ii positive value which became parallel data in the serial-parallel converter 62 is
As shown in the figure, the data is launched into the memory register 64 corresponding to the correction I memory area (2) (n-2 to n) of the nonvolatile memory 65.

It should be noted that each data other than the correction data, such as the frame loss/correction amount/photographing mode, is latched in the register 64 corresponding to the memory area (1) of the memory 65.

Then, at the 11 yen point where the data transfer is completed, the arithmetic unit 11
By setting both the R/W and ENN serial lines to L (low), the data in the register 64 is written directly into the memory 65. FIG. 7 is a diagram showing the operational relationship between R/~V and EN.

In this way, if Noyanbar 19.21 is removed after 1.0 and 2.0. By removing this, writing to the correction value data area (2) will no longer be possible.This prevents the correction value data from changing inadvertently.

Next, when the power is turned on and the need arises, the computing device 1
1 instructs the memory element 20 to transfer data by setting the EN line to L (low). When the EN line goes low, the data in memory 65 is transferred to register 6 at once.
The address of the data in the register 64 is decremented or incremented in the same way as when writing, is subjected to parallel-to-serial conversion by the serial-to-parallel converter 62, and is sent serially to the data line.

The nonvolatile digital memory device operates as described above.

In addition, to explain in detail the means for reading out the correction value written in the nonvolatile memory and correcting the control, for example, as correction data, 4-bit direct (+1, E position 2
If we decide that it is a bit or an integer, and the lower two bits are a decimal, -2,
Minor dents of 0 to +1.75, every 0.25 (Ko? Sanno comes down once).

On the other hand, this written value may not be used directly as a correction value, but may be used indirectly.

In other words, if the correction requires multiplication rather than subtraction, 1. The required number sequence is often a geometric progression, and in this case, it requires a large number of bits (2 x 4 capacity) to store direct values in memory.

Therefore, in such a case, each value of the 4-bit data (θ to 15 in hexadecimal) is associated with a value as shown in the following table.

Play this table! 5 in the device, the capacity of the memory element 20 can be maintained without increasing the sufficient degree of fl'i.
' It becomes possible to do so.

[Effects of the Invention] As described above, according to the present invention, not only can the semi-fixed resistors used in the conventional circuit board 1 be eliminated or the number thereof can be significantly reduced, but the space of the electric circuit can be greatly reduced. It is possible to obtain very excellent effects such as being small in size and easy to perform automatic adjustment.

[Brief explanation of the drawing]

FIG. 1 is an electrical adjustment circuit diagram of a camera showing a first embodiment of the present invention. FIG. 2 is an electrical adjustment circuit diagram of a camera showing a second embodiment of the invention. Fig. 2 is a time chart of the adjustment circuit; Fig. 4 is an electrical adjustment circuit diagram of a camera showing a third embodiment of the present invention; Figs. 5 to 7 show details of a nonvolatile digital memory element. Figure 5 is that! :4-grown blob 01
2 Figure 6 is a block diagram showing the memory area, Figure 7 is a diagram showing the operational relationship between EN and R/W, and Figure 8 is an electrical circuit diagram showing an example of the electrical adjustment circuit of a conventional camera. . 10 ・・・・・・A / D conversion circuit 11 ・・・・I calculation processing z;N 20 ・・・・・・・・・I''ll! Generated digital memory element procedure correction 8 ( Spontaneous) Showa 6
August 0, 278 2. Name of the invention Name of the electrical adjustment circuit of the camera
Name (037) Olympus Optical Industry Co., Ltd. 4
, Agent 5, the "Detailed Description of the Invention" column of the specification subject to amendment, Drawing 6, Contents of the amendment (1) "Programmed" written in the first line of the specification No. 8 has been changed to " This has been changed to "Program it into the computing device." (2) "is determined as follows" written in the middle of the 5th line to the 6th line of page 9 of the same page is replaced with ``The method of determining and the correction method using the data is as follows. I changed it to ``It becomes like this.'' (3) "Number of pulses n" stated in page 13, line 15 of the same
Correct it to "number of pulses N". (4) At the end of the 6th line on page 15, in the 4th line of page 16, in the 15th line and in the 17th line of page 17, respectively: own t2rR/WJ and rR/WJI respectively. I'll change it. (5) In the drawings attached to the application, the symbols "rR/~V" shown in Figures 5 and 7, respectively, are corrected to the symbols rR/WJ, respectively, as indicated in red on the attached drawings.

Claims (2)

[Claims] (1) A means for outputting exposure factor analog data including at least subject brightness information; an A/D conversion circuit for converting the amount of analog data outputted by this means into an amount of digital data; The digital data of each exposure factor to be output is input, and based on that data, the processing unit outputs exposure data such as shutter speed and aperture value necessary for exposure, and is controlled by the output of this processing unit. It has an exposure control means or an exposure information display means, and an electrically writable nonvolatile digital memory element, wherein the digital memory element controls normal operations such as exposure control accuracy and exposure instruction accuracy during the assembly process of the camera. Correction data is written to obtain the necessary accuracy during normal operation, and the arithmetic processing unit introduces a value based on the correction data to an exposure control circuit or an exposure display circuit during the arithmetic processing process during its normal operation. Camera electrical adjustment circuit. (2) The non-volatile digital memory element also has the function of storing data that needs to be retained when the camera's power supply is exhausted or when the power supply is removed. adjustment circuit.