JPH04257B2 - - Google Patents

Description

[Detailed description of the invention]

Industrial Application Field The present invention combines a camera with a strobe device that receives subject light and automatically controls the amount of light emitted (hereinafter referred to as an auto strobe), generates an aperture value control signal for the camera, and generates an aperture value control signal for the camera. The present invention relates to a strobe system device that can control a strobe system. Configuration and Problems of Conventional Examples In recent years, auto strobes have been sold that can control the aperture value of a camera by applying an aperture value control signal emitted from an auto strobe to the camera. requires two terminals to control the amount of flash light emitted and at least two terminals to control the aperture value, and in order to control a larger number of aperture values, the number of aperture values that you want to change and the light emission are required. It requires the same number of terminals as the quantity control terminals, which makes the mechanical circuit complicated.
It has not been put into practical use due to manufacturing difficulties. OBJECTS OF THE INVENTION An object of the present invention is to provide a strobe system device that can control a large number of aperture values with a small number of aperture value signal generation terminals. Structure of the Invention The device of the present invention is a strobe system device that is connected to a camera and generates an F-number signal that can control the aperture value of the camera. an F-value signal generator that generates an F-value signal for the camera in response to the calculated output signal from this circuit, and a light-receiving circuit that responds to the calculated output signal. It mainly consists of a strobe light emission stop signal generation circuit that changes the light receiving sensitivity level. DESCRIPTION OF EMBODIMENTS FIG. 1 is an electrical circuit diagram of a strobe system device showing an embodiment of the present invention, in which 1 indicates a power supply section 2, a trigger circuit 3, a flash discharge tube 4, a main discharge capacitor 5, a light emission control circuit 6, The strobe device is equipped with a voltage generation circuit 7, etc., and 8 is a logic operation device (8) which receives ASA information and F-number information, performs calculations, and outputs calculation signals for controlling the camera's F-number and strobe light emission amount. (hereinafter referred to as CPU), 9 is
A terminal for inputting information such as ASA and F value, 10 is a reference voltage generation circuit, 11 is a decoder circuit 12 with a latch that operates by receiving an output signal from the CPU,
An F-number signal generation circuit for the camera is made up of a voltage generation circuit 13; 14 is a light receiving circuit that receives reflected light from the subject; and 15 is a circuit that receives the calculation output from the CPU 8 to change the light receiving sensitivity level; A light emission stop signal generation circuit is shown that applies a light emission stop signal to the light emission control circuit 6 when the amount of received light reaches a predetermined value. When a power switch (not shown) is turned on and power is supplied from the power supply unit 2, charging of the main discharge capacitor 5 is started and at the same time, other circuits are placed in an operable state. The film sensitivity to be used and the F value information to be set for the camera are input from the input terminal 9 to the CPU 8.
When input to
Further, from the output terminals F ₁ , F ₂ , and F ₃ , an output signal for generating an F-value signal of the camera is output for a period that is appropriately set in response to the output period of the latch signal, and
After the above-mentioned period elapses, until the next F value information is input to the input terminal 9, an output signal for adjusting the light receiving sensitivity level is output, and the output signal for adjusting the light receiving sensitivity level is outputted to the decoder circuit with latch 12 and the light emission stop signal generation circuit 15 in the next stage, respectively. is input. The latch decoder circuit 12 receives signals from the output terminals F ₁ , F ₂ , F ₃ in response to the latch signal, operates, varies the states of the output terminals D ₁ to _{D 8} , and operates in response to the latch signal. Controls the operations of 13. The voltage generation circuit 13 is a decoder circuit 1 with a latch.
As a result, an F value signal that controls the aperture value of the camera is generated from the output terminal ₄₁ , and this F value signal is generated from the output terminal ₄₁ .
The F value control circuit of the camera is operated by the value signal to set the F value of the camera. The light emission stop signal generation circuit 15 is connected to the output terminal
Since the signals from F ₁ , F ₂ , and F ₃ are applied to the light-receiving sensitivity level adjustment circuit 16, the light-receiving sensitivity level here is adjusted. In addition, in this adjustment, the above-mentioned output signal for generating the F-value signal of the camera is also applied to the light receiving sensitivity level adjustment circuit 16, but its output period is shorter than that for adjusting the light receiving sensitivity level. The adjustment is made in response to an output signal for adjusting the light receiving sensitivity level. In a state where the light receiving sensitivity level adjustment circuit 16 has adjusted the light receiving sensitivity level, the trigger circuit 3
When the flash discharge tube 4 is caused to emit light toward the subject by the operation, the reflected light is received by the light receiving element 42, integrated by the integrating capacitor 43,
When this integral level applied to the input terminal 45 of 4 reaches the previously adjusted light receiving sensitivity level, the comparator 44 is inverted and its inverted output is applied to the light emission control circuit 6, which controls the operation of this circuit 6. The light emission is stopped. Next, generation of the F-number signal of the camera and adjustment of the light-receiving sensitivity level will be explained in detail.

【table】

[Table] Table 1 shows the CPU 8 corresponding to ASA and F value information.
Output signals output from output terminals F ₁ to _{F 3 of}
This represents the relationship with the reference voltage _Vr of the input terminal 46 of the comparator 44. Table 2 also shows the output signals output from the output terminals F ₁ to F ₂ of the CPU 8 in response to the period in which the latch signal is output in response to the ASA and F value information, and the decoder circuit with a latch. 12 output terminals D ₁ to _{D 8} are at high level (hereinafter referred to as H).
The low level is called L. ), and FIG. 2 shows a time chart. Now, information such as ASA and F value is input to the input terminal 9 of the CPU 8 by operating a push button or a changeover switch, etc., and the ASA and F value at T ₀ in Fig. 2 are tentatively input.
Assume ASA is 100 and F value is 5.6. Here, when F-number information for changing the camera's F-number to 4.0 is applied to the CPU 8 from the input terminal 9 at the time _T1 , a latch signal is output from the output terminal L at the time _T2 to _T3 , and on the other hand, From output terminals F ₁ to _{F 3} ,
First, F ₁ ; H, F ₂ ; H, F ₃ ; L signals are output,
The signal is input to a decoder circuit 12 with a latch. This decoder circuit 12 with a latch outputs an output signal from the output terminals _D1 to _D8 according to the signal inputted from the output terminals _F1 to _F2 by inputting the latch signal, and then the next latch signal is inputted. The output states of the output terminals D ₁ to _{D 8} are maintained until the output terminal D 1 to D 8 are turned on. Therefore, in this case, as shown in Table 2, an H signal is output only from the D ₄ terminal and the transistor 28 is turned on. The decoder circuit 12 with a latch in this embodiment uses a type of circuit that changes the states of its output terminals D ₁ to D ₈ in response to the falling edge of the latch signal. It goes without saying that a type of circuit that responds to a point in time may be used. Here, the output voltage of the reference voltage generation circuit 10 is
Assuming V _D , a voltage of V _D × R ₂₀ /R ₂₀ + R ₄₀ is obtained at the output terminal 41, and if R ₂₀ and R ₄₀ are set so that this voltage becomes V ₄₀ in Table 2, Output terminal 41
From there, a voltage of _V4 is applied to an F-number control circuit (not shown) of the camera, and the aperture value of the camera is set to 4.0. On the other hand, the above-mentioned output signals of F ₁ to _{F 3} are also applied to the light receiving sensitivity level adjustment circuit 16 to operate it, but the output signals of F ₁ to _{F 3} are adjusted in advance in response to the output period of the latch signal. From T ₄ onwards, after the determined period has elapsed, as shown in Figure 2.
F ₁ :L, F ₂ :H, F ₃ :L, and this F ₁ ~
The output signal of F ₃ maintains this state until the next F value or ASA information is input to the input terminal 9, so the F ₁ shown in Table 1 in this steady state
The light receiving sensitivity level adjustment circuit 16 is operated according to the output signal of ~ _F3 . In this state, since F ₂ is H, the transistor 37 is turned on, and a voltage of V _D ×R ₃₄ /R ₃₄ +R ₃₉ =V _B is obtained at the input terminal 46 of the comparator 44, and the aperture value of the camera is F4. The values of the resistors 34 and 39 may be set so that the input voltage at the input terminal 46 of the comparator 44 becomes _VB so that the amount of light emitted is controlled to give proper exposure to the film when the voltage is .0. Next, when inputting F value information to input terminal 9 to set the F value to 2.8 at T ₅ , first T ₆ ~
A latch signal is output at T ₇ , and at the same time the CPU
8 output terminals F ₁ to F ₃ are F ₁ ; L, F ₂ ; H, F ₃ ;
Therefore, D ₃ of the decoder circuit 12 with latch
The terminal becomes H, and as a result, the transistor 27 turns on, and V _D × R ₁₉ /R ₁₉ + R ₄₀ is obtained at the output terminal 41, and this voltage is set to V ₃ in Table 2.
If you set R ₁₉ and R ₄₀ , the camera aperture value will be set to F2.8. On the other hand, after time T ₈ after a predetermined period elapses in response to the output period of the latch signal as described above, F ₁ :H, F ₂ :L, F ₃ :
Since F ₁ is H, the transistor 36 is turned on, and a voltage of V _D ×R ₃₃ /R ₃₃ +R ₃₉ =V _A is obtained at the terminal 46 of the comparator 44, so the resistance values of the resistors 33 and 39 are You just need to set it so that the appropriate amount of light is produced when the camera is set to F2.8. Similarly _{, D 1 , D 2 , D 5 ,
The} resistors 17, _{18 ,} 21, 22,
By setting the resistance values 23 and 24, the camera's aperture can be set to the desired value using the voltage obtained at the output terminal 41. On the other hand, the light receiving sensitivity adjustment level of the strobe can be set to ASA100, F5.6. If F ₁
~ In the steady output state of F ₃ , the transistor 38
The resistance value of the resistor 35 may be set so that the voltage of V _C is obtained when the switch is turned on. That is, V ₁ = V _D × R ₁₇ / R ₄₀ + R ₁₇ V ₂ = V _D × R ₁₈ / R ₄₀ + R ₁₈ V ₅ = V _D × R ₂₁ / R ₄₀ + R ₂₁ V ₆ = V _D × R ₂₂ / R ₄₀ +R ₂₂ V ₇ = V _D × R ₂₃ / R ₄₀ + R ₂₃ V ₈ = V _D × R ₂₄ / R ₄₀ + R ₂₄ Vc = V _D × R ₃₅ / R ₃₉ + R ₃₅ , so change the resistance of each resistor. Just set the value. Next, when changing the ASA while keeping the aperture value unchanged, the instantaneous F ₁ to _{F 3} corresponding to the latch output applied to the latch decoder circuit 12
The signal does not change, so even if the ASA sensitivity is changed, the Cv value remains the same.On the other hand, the F ₁ ~ applied to the light receiving sensitivity level adjustment circuit 16 of the strobe
The steady output of _F3 changes, for example ASA100, F value
If the F value of 4.0 is not changed and is set to ASA200, F ₁ ~
F ₃ is F ₁ : L, F ₂ : H, F ₃ : L to F ₁ : H, F ₂ :
L, F ₃ : Changes to L, Vr changes from V _B to _VA , and is adjusted to the light receiving sensitivity level at ASA 200 and F4.0. Note that in this embodiment, the voltage generation circuit 13
And the light receiving sensitivity level adjustment circuit 16 has a CPU 8.
Although a transistor is used as a switch element that turns on in response to the output of the output terminals _F1 to _F3 , it is not limited to this, and other types of switch elements, such as an SCR switch element, may also be used. For example, in the case of ASA100, the F value is 2.8,
Only three values, 4.0 and 5.6, are shown, but these F values are F ₁ ~
The number of output terminals of _F3 may be increased, and each output terminal may be provided with an increased circuit including a resistor and a switch element similar to the embodiment. Further, although the CPU 8, the F-number signal generation circuit 11, the light emission stop signal generation circuit 15, etc. are shown as being separate from the strobe device 1, they may be integrated into the strobe device. Effects of the Invention The strobe system device coupled to the camera of the present invention has an F-number signal that is formed by calculating information such as ASA and F-value, and which controls the F-number of the camera, and a light-receiving sensitivity level control that controls the light-receiving sensitivity level. If a CPU with a small number of output terminals can be used to output signals, and if the F value signal generation circuit, flash stop signal generation circuit, etc. are configured as a module that can be detached from the main body of the strobe, the module and strobe Since the number of connecting terminals for the 2000 is small, the structure can be made less complicated and less expensive.
Also, the aperture value of the camera can be controlled in multiple stages.

[Brief explanation of drawings]

FIG. 1 is an electrical circuit diagram illustrating an embodiment of a strobe system device coupled to a camera of the present invention.
FIG. 2 is a time chart for explaining the operation of the present invention. 1... Strobe device, 8... CPU, 10...
Reference voltage generation circuit, 11...F value signal generation circuit,
15...Light emission stop signal generation circuit.

Claims (1)

[Claims] 1 A flash discharge tube that emits light using the charging energy of a main discharge capacitor that is charged at high voltage, and a light receiving circuit that receives reflected light from the subject, and a light emission stop that generates a light emission stop signal when the amount of received light reaches a predetermined amount. A signal generation circuit, a light emission control circuit that operates upon receiving the light emission stop signal and stops light emission of the flash discharge tube, and performs arithmetic operation based on input of information such as film sensitivity and F value, and produces a predetermined output. a logic operation circuit that generates a latch signal from a terminal, a first operation signal that is output from a signal output terminal for a period corresponding to the output period of the latch signal, and a second operation signal that is output after the output of the first operation signal is finished; , the latch signal from the logic operation circuit and the first
an F-number signal that operates in response to a calculation signal, generates an F-number signal for the camera, applies it to the camera, and holds the F-number signal until the next latch signal is applied from the logical operation circuit; a generation circuit; and a light reception sensitivity level adjustment circuit that receives the second calculation signal from the logic operation circuit and adjusts the light reception sensitivity level of the light reception circuit in the light emission stop signal generation circuit, and A strobe system device coupled to a camera that applies a value signal.