JPH0364050B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an information setting device, and more particularly to a camera information setting device for setting film sensitivity information and the like.

In recent years, a type of setting device has been adopted as the above device, which stores setting information as an electrical signal by supplying pulses or digital values to a memory circuit such as a counter when a switch is pressed, etc. .

In this type of device, the stored values in the memory circuit are maintained by power supplied from the power supply battery, so when the battery is replaced or the battery output drops, the power supply to the memory circuit is cut off and the memory circuit is set. The value is cleared.

Therefore, when trying to perform a shooting operation after replacing the battery, etc., it is necessary to set the information again, but the photographer may not be aware of this and
There is a drawback that proper exposure cannot be obtained when the release operation is performed.

The present invention has been made in view of this point, and is an information setting device including a memory circuit that stores exposure information set by an exposure information setting operation member as an electrical signal and holds the stored value while power is supplied. In the above-mentioned case, a signal forming circuit outputs a power supply start signal when power supply to the memory circuit starts, and a warning means for issuing a warning or a prohibition means for prohibiting a release operation in response to the power supply start signal is provided. In some cases, the above-mentioned drawbacks are solved by giving a warning or prohibiting the release operation.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is an external view showing the appearance of a camera having a film sensitivity information memory circuit according to the present invention. In the figure, 1 is the camera body, 2 is the photographic lens, 3 is the release button, 4 is the LED external display,
5 is an LCD external display, and 6 is a film sensitivity information input switch.

FIG. 2 is a circuit diagram showing an example of the circuit configuration of the first illustrated camera.

In FIG. 2, 7 is a power up clear circuit which sends out a pulse that becomes high level for a short time when the power supply battery is stored in the battery compartment of the camera or when the power supply voltage returns after a temporary drop. 8-1
0 is a D-type flip-flop (hereinafter referred to as DFF).
These DFFs constitute a ring counter as a memory circuit. The set terminal of DFF8 and the reset terminals of DFF9 and DFF10 are connected to the output Q of the power up clear circuit 7, and the pulse from the clear circuit 7 causes the DFF to clear.
8 is set, and DFFs 9 and 10 are reset.

Further, the clock terminals of the DFFs 8 to 10 are connected to the switch 6, and when the switch 6 is pressed down, a counting operation is performed. 11 connects the reset terminal to the Q output of the power up clear circuit 7,
This is a detection DFF whose clock terminal is connected to the switch 6 and the battery output Vc is applied to the D terminal.

14 is an AND gate whose one input terminal is connected to the switch 3 that is linked to the release button 3, and the other input terminal is connected to the Q output of the DFF 11, and the output of this gate is connected to a release activation circuit (not shown). are doing. With the above configuration, the AND gate is
Only when the Q output of the DFF 11 is at a high level, a release control circuit is configured that sends a release signal to the release activation circuit by turning on the switch 3' to permit the release operation.

15 is an inverter connected to the Q output of the DFF 11, and 4 is an external LED display shown in the first figure.

13 is the DFF that constitutes the above ring counter
The LCD decoder driver connects inputs i ₁ to i ₃ to outputs 8 to 10, and the driver selects three types of film sensitivity values according to the output status of the counter.
Display on the LCD external display shown in the figure. this
The relationship between the input signal status to the inputs i ₁ to _{i 3} of the LCD decoder driver and the display value of the external display 5 is as follows.
As shown in the figure.

Reference numeral 12 denotes an exposure control circuit, into which the film sensitivity values set in the counters (DFF8-10) are input, and exposure calculation control is performed in accordance with the film sensitivity values and photometric output.

Next, the operations of the first and second illustrated embodiments will be explained.

It is now assumed that the DFF 8 is in the set state, the DFFs 9 and 10 are in the reset state, and a high level is applied to the input _{i 1} of the driver 13, and a low level is applied to the inputs i 2 and i ₃ . In this state, "25" is displayed on the display 5 as shown in Figure 3, and the film sensitivity is ASA.
It is displayed that it is set to 25.

When the switch 6 is pressed once in this state, the ring counter (DFF8 to 10) is activated, the state is shifted by 1 bit, DFF8 and 10 output a low level, DFF9 outputs a high level, and "100" is displayed on the display 5. The displayed film sensitivity is ASA100.
Displays what has been set.

When the switch 6 is further pressed in this state, the value of the ring counter is further shifted by one bit, and "400" is displayed on the display 5, indicating that ASA 400 has been set. Also, when the switch 6 is pressed after this, the value of the ring counter shifts by 1 bit each time, and the display 5 shows "25" →
``100'' → ``400'' → ``25'' will be displayed toggle each time the switch 6 is pressed, and the switch 6 must be pressed repeatedly until the display value that the photographer should set is displayed on the display 5. A desired film sensitivity value is set in .

After this, when the release button 3 is pressed, the switch 3' is turned on. At this time, the DFF11 is also sending out a high level from the Q output by pressing the switch 6, so the gate 14 is turned on by turning on the switch 3'.
sends out a high-level signal to activate the release activation circuit and start exposure control.

Also, the above ring counter (DFF8-10)
Since the count value is input to the exposure control circuit 12, the exposure control circuit 12 performs exposure control based on the film sensitivity value set by the ring counter and the photometry value from the photometry circuit (not shown), and adjusts the set film value. Appropriate exposure control is performed based on sensitivity.

Next, a case will be described in which the battery is removed from the camera and replaced, or the battery output temporarily decreases and then returns to a predetermined potential.

In this case, the power up clear circuit PUC operates to set DFF8 and reset DFF9 and DFF10. Yotsute Ring Counter (DFF8,
9 and 10), a digital value corresponding to the film sensitivity ASA 25 is set and displayed on the display 5.

Further, the DFF 11 is also reset by a pulse from the power up clear circuit, and the Q output of the DFF sends out a low level. Therefore, the LED 4 lights up to warn the photographer of the need to reset the film sensitivity information. Also, in this state, release button 3
Even if the switch 3' is turned on by pressing , the AND gate 14 cannot send out a high level signal, so the release operation is prohibited. Therefore, as mentioned above,
DFF8 due to battery replacement or temporary decrease in battery output
When the film sensitivity value set to ~10 is erased, the camera will notify you that it is necessary to reset the film sensitivity, and even if you accidentally perform the release operation, the release operation will be prohibited and the film sensitivity value will be correct. Incorrect exposure due to the value not being set is prevented.

In the above case, when the switch 6 is pressed and the film sensitivity setting operation is performed as described above,
When the desired film sensitivity is set on the ring counter and the switch 6 is turned on in the film sensitivity setting operation, the Q output of the DFF 11 becomes high level, so the LED 4 turns off, and the AND gate 14 turns on the release switch 3'. be able to respond,
After resetting the film sensitivity, the release operation becomes possible.

As shown in Figure 4, it is possible to detect that the battery has been replaced or that the battery output has temporarily decreased by comparing the partial voltage of the battery BAT output with the constant voltage of the constant voltage circuit CON. This is done by the comparator COM which outputs a high level when the voltage is above a predetermined value, and the power up clear circuit PUC mentioned above.
operates in response to a rising signal from the comparator COM. Further, as the above-mentioned detection method, a switch that is turned on when the battery is stored in the battery compartment is installed, and when the switch is turned on, the power-up clear circuit is activated, or a transistor is installed in place of the above-mentioned comparator to check the battery voltage. The power up clear circuit PUC may be turned on when the transistor is greater than a predetermined value, and the power up clear circuit PUC may be operated when the transistor is turned on from off.

Next, an embodiment of a circuit in which the present invention is applied to a camera whose operation is controlled using a microprocessor will be described with reference to FIGS. 5 and 6.

FIG. 5 is a circuit connection diagram showing another embodiment of the present invention.

In the figure, CPU is a microprocessor that controls camera operations, SW3 is a release switch that is linked to the release button, and SW6 is a film sensitivity information input switch.

13 is an LCD decoder driver, and 5 is a 7-segment, 3-digit LCD external display shown in the first diagram.
M1 is a memory for storing setting film sensitivity information, M2 is a memory for storing information as to whether or not the battery has been replaced, and AV1 is an aperture control circuit.
Tr1, Tr2, and Tr3 are transistors, and each transistor is connected to the output port of the microprocessor CPU. In addition, magnet Mg1 is connected to the collector of Tr1, and magnet Mg1 is connected to the collector of Tr1.
Mg2 is connected to the magnet Mg2, and a magnet Mg3 is connected to the Tr3.

Mg1 is the shutter release operation start magnet, transistor Tr1 is turned on, and the magnet Mg
When power is applied to 1, a quick return mirror (not shown) flips up.

Mg2 is a front curtain running start magnet, and when the transistor Tr2 is turned on and the magnet Mg2 is energized, the shutter front curtain (not shown) starts running.

Mg3 is a trailing curtain running start magnet, and when the transistor Tr3 is turned on and the magnet Mg3 is energized, the shutter trailing curtain (not shown) starts running.

Next, the operation of the circuit shown in FIG. 5 will be explained using FIG. 4.

First, when a power supply battery (not shown) is attached to the battery compartment of the camera for battery replacement, the microprocessor starts operating according to the program. As shown in FIG. 6, the camera first reads out what kind of data is written in the memory M2. At this time, since the power is turned on, FF, φφ, or random data is written in the memory M2. In the branch instruction for this purpose, the data 55 is written in the memory M2, and the data is sent to the LCD decoder driver 13 via the data bus line DBφ in order to display a warning on the LCD 5.

As a result, the LCD external display 5 displays a reduced number of points.
A warning is given to the photographer to the effect that ``the memory of the film sensitivity information has been erased, so set the film sensitivity.'' Even if the photographer presses the release switch SW3 at this time, no release operation is performed because the camera is stopped.

The photographer presses the film sensitivity information input switch SW6.
When you operate , the program moves to , and the camera stores the film sensitivity information as ASA100 in memory M.
At the same time, data is sent to the LCD decoder driver 13 via the data bus line DBφ so that "1□□" is displayed on the LCD 5. In addition, the point reduction warning from the display 5 is prohibited at the transition to . After that, move to Figure 6,
The photographer presses the film sensitivity information input switch SW.
It stays until you let go of 6.

The photographer presses the film sensitivity information input switch SW6.
When released, the program returns to START.The next branch instruction reads and checks the contents of memory #2 again. At this time, as described above, data 55 has been written in memory #2, so the program moves to . At this point, it is determined whether or not the photographer has pressed the film sensitivity information input switch SW6, and the program branches. However, if the photographer has not pressed the film sensitivity information input switch, the program moves to the next step. Then, it judges whether the switch is pressed or not and branches, but if the release switch is not pressed, it returns to START again.

After that START →→→→ START →…
This repeats, and the loop continues for as long as the photographer takes his hand off the camera.

Now, in this state, when the film sensitivity information input switch SW6 is turned on next time, the program proceeds to the branch instruction. Then, the contents of the memory M1 are read out and it is determined whether the ASA 100 or not. When the contents of memory M1 are ASA100,
Then the camera will set the film sensitivity information to ASA400.
The data is written in the memory M1 as follows, and the data is output to the LCD decoder driver 13 in order to display "4□□" on the LCD 5. After that, wait until the photographer releases the film sensitivity information input switch SW6 and turns it off.
Then return to START, and then START again →
→→→ START →……Repeat.

When the film sensitivity information input switch SW6 is turned on again from this state, the process moves to another branch instruction, and the content of the memory M1 is read out and judged, but if the ASA is 400, the process moves to the branch command I'll be flying soon. , the camera writes the film sensitivity information as ASA25 to memory M1, and then displays it again on LCD5.
25" is output to the LCD decoder driver 13 so as to display a 25" screen.

Thereafter, the process shifts to ``START'' in the same manner, and after waiting until the photographer turns off the film sensitivity information input switch SW6, the process returns to START.

After that, when the film sensitivity information input switch SW6 is turned on, it jumps to the branch command, but the memory M
Since the data of the film sensitivity information ASA25 is written in the memory M1, the film sensitivity information is written as ASA100 again in the sequence →→→. “1□□” is displayed on LCD5.

As explained above, each time the photographer operates the film sensitivity information input switch from off to on, the display changes from "1□□" to "4□□" to "25", and the ASA sensitivity information changes from 100 to Inform the photographer that the camera is switching from 400 to 25.

Now, I have explained the operation sequence after turning on the power battery, but if the photographer drops the camera while transporting it, the power battery floats and the power supply is temporarily cut off, erasing the memory of the film sensitivity information. If you do this, the data 55 in memory M2 will also be erased at the same time, so a warning will be displayed when the program moves from the branch instruction to
Since the release operation is prohibited, photographing with incorrect film sensitivity information is prohibited.

If the film sensitivity information is correctly stored, when the release switch SW3 is pressed, the program jumps to a release routine (not shown) using a branch command.

In the release routine, the microprocessor
Reads the film sensitivity from the memory M1, sends an energizing signal to the transistors Tr1, Tr2, and Tr3, and writes aperture value data to the aperture control circuit, controls the shutter speed and aperture value, respectively, and performs exposure adjustment commensurate with the film sensitivity. .

As described above, in the present invention, when the power supply to the memory circuit that stores the set film sensitivity is cut off when replacing the battery, etc., and the value stored in the memory circuit is erased, a warning is displayed to indicate this, Since the release operation is prohibited in this state, it is possible to prevent exposure control from being erroneously performed in accordance with the film sensitivity in the above-mentioned case.

In the embodiment, the information on whether or not the battery has been replaced is stored separately from the memory that stores the film sensitivity. For example, in the embodiment shown in FIG. 2, the output of the power up clear circuit PUC is
Connect to the reset terminal of DFF8, detect the contents of the ring counter (DFF8-10) with a decoder, etc., and generate an output (low level) when all DFF8-10 are in the reset state.
AND gate 14 instead of Q output of DFF11
By inputting this information, the memory for storing the film sensitivity can also be used as the memory for storing information on whether or not the battery has been replaced.

Furthermore, although an LED is used as the display 4, it is of course possible to use a display means that warns with a voice or a buzzer instead.

In addition, the display 5 may be flashed as the above warning,
You can turn it off or display special numbers or symbols.

Further, although the release is prohibited in the embodiment, only a warning operation may be used, and in this case, the film sensitivity may be set to the most frequently used value such as ASA100 instead of ASA25 in the embodiment of FIG. Also good.

Further, in the embodiment, information is set by pressing a push button switch, but for example, an information setting member of the type that links the switch to a dial and turns the switch on and off by rotating the dial to set the information may be used. It may be provided.

Further, in the embodiment, film sensitivity is exemplified as information to be set, but it goes without saying that the present invention is also applicable to setting shutter and aperture values.

[Brief explanation of drawings]

FIG. 1 is an external view showing an embodiment of a camera in which an information setting device according to the present invention is adopted, and FIG.
A circuit diagram showing the circuit of the illustrated camera, FIG. 3 is an explanatory diagram for explaining the operation of the second illustrated circuit, and FIG. 4 is an example of a detection circuit for operating the power up clear circuit illustrated in the second figure. Circuit diagram showing 5th
The figure is a circuit diagram showing another embodiment of the present invention, and FIG. 6 is an explanatory diagram showing a flow for explaining the operation of the circuit shown in FIG. 8, 9, 10, 11...D flip-flop, 14...AND gate, 4...display device.

Claims (1)

[Claims] 1. In a camera equipped with a memory circuit that retains preset information while power is supplied from the power supply circuit, when the power supply to the memory circuit is restarted after the power supply from the power supply circuit has stopped, or when the power is restored after the power has decreased. a signal forming circuit that outputs a signal at a certain time; the signal from the signal forming circuit forcibly sets at least part of the information in the memory circuit to specific information; and the specific information is set in the memory circuit. A camera characterized in that it is provided with a prohibition circuit that prohibits a release operation by operating a release operation member when the camera is in use.