JP2775799B2 - Camera with built-in electronic flash device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a camera with a built-in electronic flash device equipped with a multi-strobe or a red-eye prevention device.

2. Description of the Related Art Conventionally, a so-called multi-strobe, in which a flash is emitted several times to several tens of times while a shutter is opened and light is adjusted and emitted at a predetermined time interval to separately capture a moving object, is known. In this multi-strobe, a plurality of capacitors are provided in order to continuously perform flash light emission a plurality of times, the first light emission is performed by the charge of one capacitor, and the second light emission is performed by the charge of the other capacitor. This is because if a single capacitor is used in a time-division manner, it takes a long time to charge the battery, making it impossible to perform detailed disassembly shooting. And the strobe color tends to be bluish.

On the other hand, the red-eye phenomenon, that is, the human eye sometimes shines red or gold in color photography using an electronic flash device. This phenomenon occurs when the flash of the light emitting portion of the electronic flash device that has passed through the pupil of the eye is reflected by the retina, and the reflected light is reflected on the film surface. Since there are many capillaries in the retina of the eye and the hemoglobin in the blood is red, the reflected light appears reddish.

Techniques for preventing this red-eye effect have been conventionally known. For example, a plurality of capacitors are provided, and the charged charge of one of the capacitors is pre-irradiated with red-eye prevention light for reducing the human pupil prior to flash light emission, and the other capacitor is charged when the pupil becomes almost the minimum diameter. There is a technique in which a main flash device emits main light by using electric charges to perform photographing. In this case as well, a plurality of capacitors are used. However, it takes a long time to charge a single capacitor, and the main light emission cannot be performed immediately after the irradiation of the red-eye preventing light.

(Problems to be Solved by the Invention) However, when providing a camera with a built-in electronic flash device equipped with the above-mentioned multi-strobe and a red-eye prevention device, both require a plurality of capacitors for charging. There is a problem that the camera or the entire device becomes extremely large, which leads to an increase in manufacturing cost.

Regarding the red-eye prevention device, when the release button is fully pressed, the red-eye prevention light is pre-irradiated, and then after a predetermined time elapses, the main light is emitted, so that a time lag occurs after pressing the release button until the actual shutter is released. And there is a problem that a photo opportunity is missed.

Further, when the main flash is emitted by the charge of the main condenser within a short shooting distance to the subject, for example, within 1 m, the exposure tends to be over unless the shutter is stopped down below the minimum aperture, so that an appropriate photograph can be obtained. Can not.

The present invention has been made in view of the above-described problems, and does not increase the size of the camera or the entire device, does not cause an increase in manufacturing cost, and performs appropriate photographing.
In other words, it is an object of the present invention to provide an electronic flash device camera capable of taking a picture with an appropriate exposure and a proper photo opportunity intended by a photographer.

(Means for Solving the Problems) In order to solve the above problems, the present invention provides a shutter (7), a discharge tube (8a) for emitting a flash of light to a subject, and the discharge tube. A main capacitor (8b) charged with a charge for emitting light, and a sub-capacitor (8c) charged with a charge for causing the discharge tube to emit light,
An energizing light emitting means (8d) for emitting a flash for photographing only once from the discharge tube while the shutter is open, and emitting a plurality of flashes for photographing from the discharge tube a plurality of times while the shutter is open Multi-light emitting means (8e) for emitting red-eye preventing flash from the discharge tube to reduce the pupil of the subject prior to opening the shutter; and a normal flash photography mode and multi-flash. Selecting means (9) for selecting one of a photographing mode and a red-eye prevention mode; and control means (selective means for selectively controlling the normal light-emitting means, the multi-light-emitting means and the red-eye preventing means according to the output of the selecting means (9). The control means (1) comprises: when the normal flash photography mode is selected by the selection means (9), the control means (1) uses the charge of the main capacitor (8b) to charge the normal light emission means (8d). The flash for photography is emitted only once from the discharge tube (8a) via the discharge tube, and when the multi-flash photography mode is selected by the selecting means (9), the main and sub capacitors (8b, 8c) The flashlight for photography is emitted from the discharge tube (8a) via the multi-emission means (8e) by one of the charged charges, and after a predetermined time from the emission, the multi-emission means (8e) is used by the other. The flashlight for photographing is emitted from the discharge tube (8a) through the sub-capacitor (8a), and when the red-eye prevention mode is selected by the selection means (9), the red-eye prevention means ( After emitting the red-eye preventing flash from the discharge tube (8a) via 8f),
The photographing flash is emitted only once from the discharge tube (8a) via the normal light emitting means (8d) by the charge of the main capacitor (8b).

In the invention according to claim 2, the selection means (9) can further select a multi-flash red-eye prevention mode, and the control means (1) controls the sub-flash when the multi-flash red-eye prevention mode is selected. After the red-eye prevention flash is emitted from the discharge tube (8a) through the red-eye prevention means (8f) by the charge of the capacitor (8c), the charge of the main and sub-capacitors (8b, 8c) is reduced. The discharge tube (8a) via the multi-light emitting means (8e) by one of them.
Then, the flash for photography is emitted from the discharge tube (8a) via the multi-emission means (8e) at a predetermined time after the emission, and the flash for photography is emitted by the other.

According to the third aspect of the present invention, the signal output means (SW) outputs the first operation signal by the first operation to the release operation member, and outputs the second operation signal by the second operation following the first operation.
1, SW2), a shutter (7), a discharge tube (8a) for emitting a flash of light to a subject, a normal light emitting means (8d) for emitting a flash for photography from the discharge tube while the shutter is open, Prior to opening the shutter, a red-eye prevention unit (8f) for emitting red-eye prevention flash light from the discharge tube for reducing the pupil of the subject is selected from the normal flash photography mode and the red-eye prevention mode. And a control means (1) for selectively controlling the normal light emitting means and the red-eye prevention means in accordance with an output of the selection means (9), wherein the control means (1) comprises: When the normal flash photography mode is selected by the selection means (9), the shutter (7) is opened and the photography flash light is emitted according to the output of the second operation signal, and the selection means (9) When the red-eye prevention mode is selected by Illuminating the red-eye prevention flash in response to the output of the first operation signal, and causing the pupil of the subject to be reduced to the effective red-eye prevention effective diameter by the emission of the second operation signal during a standby period. The opening of the shutter (7) according to the output of the shutter (7) is prohibited, and thereafter, when the pupil enters a red-eye prevention effective period in which the pupil is reduced to the red-eye prevention effective diameter, the shutter (7) is released according to the output of the second operation signal. (7) is released and the flash for photography is emitted,
After the red-eye prevention effective period has elapsed and the pupil has expanded beyond the red-eye prevention effective diameter, opening of the shutter (7) in accordance with the output of the second operation signal is prohibited again.

According to the invention of claim 4, when the second operation signal is output after the red-eye prevention effective period by the emission of the red-eye prevention flash has elapsed, the control means (1) responds to the output. Then, the red-eye prevention flash is emitted again, and after the standby period has elapsed and the red-eye prevention effective period has elapsed, the shutter (7) is opened and the photographing flash is emitted.

According to the invention of claim 5, a shutter (7), a discharge tube (8a) that emits flash light to a subject, and a main capacitor (8b) that is charged with electric charge for causing the discharge tube to emit light,
A sub-condenser (8c) having a charge capacity for causing the discharge tube to emit light and having a charge capacity smaller than the charge capacity of the main capacitor, and a normal light emitting means (e.g., a flash light for photographing emitted from the discharge tube during opening of the shutter; 8d), a red-eye prevention means (8f) for emitting a red-eye prevention flash from the discharge tube for reducing the pupil of the subject prior to opening of the shutter, and a condition that the distance to the subject is equal to or less than a predetermined value. A distance measuring means (2) for outputting a short distance signal upon detection;
Selecting means (9) for selecting one of the normal flash photography mode and the red-eye prevention mode; and control means (selective means for selectively controlling the normal light-emitting means and the red-eye prevention means according to the output of the selecting means (9). 1) and when the normal flash photography mode is selected by the selection means (9), the control means (1) emits the photography flash light by the charge of the main capacitor (8b). (9) When the red-eye prevention mode is selected, the flash for preventing red-eye is emitted by the charge of the sub-condenser (8c), and then the flash for photographing is emitted by the charge of the main capacitor (8b). However, when the short-distance signal is output from the distance measuring means (2), regardless of which of the normal flash photography mode and the red-eye prevention mode is selected by the selection means (9), The charges of the serial sub-condenser (8c) was set to emit the photographing flashing.

(Operation) According to the first and second aspects of the invention, when the multi-flash red-eye prevention mode is selected by the selection means (9), the red-eye prevention is performed by charging the sub-condenser (8c) prior to opening the shutter. A red-eye preventing flash is emitted from the discharge tube (8a) via the means (8f). Subsequently, a flash for photographing is emitted from the discharge tube (8a) via the multi-emission means (8e) by one of the charged charges of the main or sub-condenser (8c, 8d), and after a predetermined time from this emission. On the other hand, a flash for photography is emitted from the discharge tube (8a) via the multi-light emitting means (8e).

According to this, the capacitor for charging the electric charge for irradiating the red-eye preventing flash and the capacitor for charging the electric charge for the multi-emission are used as a single capacitor (8c). There is no increase in manufacturing cost without an increase in size.

According to the third and fourth aspects of the present invention, when the red-eye prevention mode is selected by the selection means (9), the red-eye prevention means is provided in response to the output of the first operation signal from the signal output means (SW1, SW2). A red-eye preventing flash is emitted from the discharge tube (8a) via (8f). The opening of the shutter (7) according to the output of the second operation signal is prohibited during a standby time required for the pupil of the subject to be reduced to the effective red-eye preventing diameter by the emission of the red-eye preventing flash, and thereafter, In the red-eye prevention effective diameter period in which the pupil is reduced to the red-eye prevention effective diameter, the shutter (7) is opened and the flash for photographing is emitted according to the output of the second operation signal, and the red-eye prevention effective period elapses. After the pupil expands beyond the red-eye prevention effective diameter, the opening of the shutter (7) according to the output of the second operation signal is prohibited again.

According to this, the red-eye prevention flash is generated by the signal output means (SW
1, SW2) is emitted according to the output of the first operation signal instead of the output of the second operation signal, so that the occurrence of a time lag is reduced and a photo opportunity is not missed.

On the other hand, when the second operation signal is output from the signal output means (SW1, SW2) after the red-eye prevention effective period has elapsed, the red-eye prevention flash light is emitted again in response to the output, and the standby time has elapsed. After entering the red-eye prevention effective period, the shutter (7) is opened and the flash for photographing is emitted.

In this case only, the red-eye preventing flash is emitted in response to the output of the second operation signal, which causes a time lag. However, red-eye preventing measures for the subject are surely taken. .

According to the invention of claim 5, when the short-distance signal is output from the distance measuring means (2), the selection means (9) selects either the normal flash photography mode or the red-eye prevention mode. The flash for photography is emitted by the charge of the sub-condenser (8c). Therefore, even when the subject is in close proximity, a photograph that would be overexposed is not taken.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings. First, a first embodiment of the present invention will be described with reference to FIGS. 1 and 2 (a) to (d).

In FIG. 1 showing the overall configuration, a distance measuring means 2, a photometric circuit 3, an exposure control circuit 4, a motor drive circuit 5, and switches SW1 and SW2 are connected to a CPU 1. The distance measuring means 2
Distance measurement information corresponding to the distance to the subject is output, and the photometry circuit 3 outputs luminance information relating to the luminance of the subject.

A focusing motor 6 is connected to the motor drive circuit 5, and the motor 6 drives a focusing lens (not shown) based on a lens drive signal from the CPU 1 to perform focusing.

The exposure control circuit 4 is connected to an exposure control device 7 such as a shutter and an aperture, and drives the exposure control device 7 based on the exposure value calculated by the CPU 1 to perform photographing.

The switches SW1 and SW2 are switches that are turned on in conjunction with the operation of a release button (not shown) .When the switch SW1 is turned on while the release button is half-pressed, a half-press signal is output to the CPU1, and the switch SW2 is turned on when the switch is fully pressed. When turned on, all push signals are output to CPU1.

The CPU 1 activates the distance measuring circuit 2 and the photometric circuit 3 by turning on the half-press switch SW1, and calculates a lens driving amount for focusing based on the distance measuring information.
An exposure value such as a shutter speed or an aperture value is calculated based on the luminance information. When the full-press switch SW2 is turned on, a lens drive signal for driving the photographing lens based on the calculated lens drive amount is output to the motor drive circuit 5, and the exposure control circuit 4 is operated to perform photographing. .

An electronic flash 8 is connected to the CPU 1. This electronic flash device 8 includes a discharge tube 8a, a main capacitor 8b,
Sub capacitor 8c, normal light emitting means 8d, multi light emitting means 8
e, a red-eye prevention means 8f, a charging circuit 8g, and a light emission control circuit 8h.

The main and sub capacitors 8b and 8c perform charging for causing the discharge tube 8a to emit light. The charging capacity of the main capacitor 8b is larger than that of the sub capacitor 8c.

The normal light emitting means 8d emits a flash for photography only once from the discharge tube 8a while the shutter (not shown) is open.

The multi-emission means 8e emits a flash for photographing a plurality of times from the discharge tube 8a at predetermined intervals while a shutter (not shown) is opened.

The red-eye preventing means 8f causes the discharge tube 8a to emit red-eye preventing flash light for reducing the pupil of the subject before opening a shutter (not shown).

The charging circuit 8g charges the main and sub-capacitors 8e and 8f in response to a command from the CPU 1, outputs a charging completion signal after charging is completed, and stops charging.

The light emission control circuit 8h causes the discharge tube 8a to emit main light in response to the light emission start signal from the CPU 1, and stops the main light emission in response to the light emission stop signal. When the subject brightness is higher than a predetermined value in the automatic light emission mode or when the light emission prohibition mode is selected, light emission from the discharge tube 8a is prohibited.

Here, the flash photography mode will be described. The flash photography mode can be roughly classified into four modes: a normal flash photography mode, a multi-flash photography mode, a red-eye prevention mode, and a multi-flash red-eye prevention mode. ing.

Then, when the normal flash photography mode is selected by the selection means 9, the CPU 1 causes the discharge lamp 8a to emit the flashlight for photography only once from the discharge tube 8a via the normal light emission means 8d by the charge of the main capacitor 8b. The normal flash photography mode further includes an automatic light emission mode in which light emission is automatically performed when the object is detected to have low luminance, a forced light emission mode in which light emission is performed regardless of luminance, and a light emission inhibition mode in which light emission is inhibited. There are each.

When the multi-flash photography mode is selected by the selection means 9, the CPU 1 causes the discharge tube 8a to emit flash light for photography from the discharge tube 8a via the multi-light emission means 8e by using one of the main and sub-condensers 8b and 8c. At a predetermined time after the light emission, the other device causes the discharge tube 8a to emit flashlight for photographing via the multiple light emitting means 8e.

Further, when the red-eye prevention mode is selected by the selection means 9, the CPU 1 emits a red-eye prevention flash from the discharge tube 8a through the red-eye prevention means 8f by the charge of the sub-capacitor 8c, and then charges the main capacitor 8b. The flash for photography is emitted only once from the discharge tube 8a via the normal light emitting means 8d by the electric charge.

Further, when the multi-flash red-eye prevention mode is selected by the selection means 9, the CPU 1 emits a red-eye prevention flash light from the discharge tube 8a through the red-eye prevention means 8f by the charge of the sub-condenser 8c. Sub capacitor 8
b, 8c, the multi-light emitting means 8
e, a flash light for photography is emitted from the discharge tube 8a via the e, and after a predetermined time from this emission, the other flash light emitting means
Flash light for photography is emitted again from the discharge tube 8a via 8e.

Next, FIGS. 2 (a), (b), (c), (d) to 4
The control procedure by the CPU 1 will be described based on the flowchart of FIG.

Half-press switch SW1 when normal processing is being executed
Is turned on, the program shown in FIG. 2A is started by interruption. First, at step S1 in FIG.
And outputs a command signal to the charging circuit 8d to start charging the main and sub capacitors 8e and 8f. Next, in step S2, the distance measurement information from the distance measurement circuit 2 and the photometry information from the photometry circuit 3 are read, and the flow advances to step S3. Step S3
In step S4, the lens drive amount for focusing is calculated based on the read distance measurement information. In step S4, the exposure value is calculated based on the read luminance information.
Proceed to S5.

In step S5, it is determined whether or not the half-press switch SW1 is turned on. If a negative determination is made, the process returns to the normal process, and if an affirmative determination is made, the process proceeds to step S6. In step S6, it is determined whether or not shooting is performed using the electronic flash device 8. This is determined, for example, based on whether the mode is the light emission prohibition mode, or whether the luminance information read in step S2 is higher than a predetermined reference value. If step S6 is denied, the process proceeds to step S9, and if affirmed, it is determined in step S7 whether the charging of the main and sub capacitors 8e and 8f is completed. If the charging completion signal has been output from the charging circuit 8d and the step S7 is affirmed, the process proceeds to a step S8. If the charging completion signal is not output and the step S7 is denied, the process returns to the step S5. In step S8, charging is stopped, and the process proceeds to step S9, where it is determined whether the half-press switch SW1 is turned on. If a negative determination is made, the process returns to the normal process. If an affirmative determination is made, it is determined in step S10 whether the full-press switch SW2 is turned on. If step S10 is affirmed, the process proceeds to step S11, and if negative, the process returns to step S9.

In step S11, a lens drive signal corresponding to the lens drive amount calculated in step S3 is output, and a focusing lens (not shown) is driven by the motor 6 via the motor drive circuit 5 to the focusing position.
Proceed to 2.

In step S12, it is determined whether or not shooting is performed using the electronic flash device 8. If a negative determination is made, step S35
If a positive determination is made, it is determined in step S13 whether or not special flash photography has been performed.

Here, special flash photography will be described. The special flash photography means a multi-flash photography mode (decomposition photography mode) and a multi-flash red-eye prevention mode. The multi-flash photography mode has three modes: a simultaneous flash mode, a strong flash mode, and a weak flash mode. A mode in which a red-eye prevention mode is added to each of these three modes is a multi-flash red-eye prevention mode. That is, there are a case of the simultaneous light emission mode and the red-eye prevention mode and a case of the strong light emission mode and the red-eye prevention mode.

Then, when the simultaneous light emission mode is selected, the CPU 1 causes the discharge tube 8a to emit the flash light only once by the charge of the main and sub capacitors 8b and 8c via the normal light emitting means 8d.

In this way, the operation is not different from the normal flash photography mode described above, but the charged electric charge is stored in the main and sub capacitor 8.
Since it is based on b and 8c, the light emission amount is larger than that in the normal flash photography mode, and the illuminable distance range becomes wider.

Further, when the strong light emission mode is selected, the CPU 1 causes the discharge lamp 8a to emit flashlight for photographing from the discharge tube 8a via the multi-emission means 8e by the charge of the main capacitor 8b, and after a predetermined time from this emission, the sub-capacitor 8c The flashlight for photography is emitted again by the charged electric charge of. In this strong light emission mode, a photograph in which the subject to be photographed by the first flash of the photographing flash (which is often a moving body in the decomposition photographing) is emphasized is photographed.

Further, when the weak light emission mode is selected, the CPU 1 causes the discharge lamp 8a to emit flashlight for photography from the discharge tube 8a through the multi-emission means 8e by the charge of the sub-capacitor 8c, and after a predetermined time from the emission, the main capacitor. The flash for photography is again emitted from the discharge tube 8a via the multi-emission means 8e by the charge of 8b. In the strong light emission mode, contrary to the strong light emission mode, a photograph in which the subject to be photographed by the second flash of the photographing flash is emphasized is taken.

On the other hand, when the multi-flash red-eye prevention mode is selected, the CPU 1 uses the charge stored in the sub-condenser 8c to prevent the red-eye prevention means.
After emitting a red-eye preventing flash from the discharge tube 8a via 8f, for example, a flash for photography is emitted from the discharge tube 8a via the multi-emission means 8e by the charge of the main capacitor 8b, for a predetermined time from this emission. Put the sub capacitor 8c
Discharge tube 8a through the multi-emission means 8e by the charge of
Flash light for photography is emitted again.

By the way, if an affirmative determination is made in step S13, that is, if it is determined that it is the special flash photography, the process proceeds to step S14, and it is determined whether or not the red-eye prevention mode is set. When step S14 is denied, the process proceeds to step S23, and when affirmed, in step S15, the fact that the red-eye preventing flash is emitted prior to the main emission is displayed on the external LCD. Here, in the present embodiment, the display is performed by the external LCD, but the display may also be used as an LED that issues a warning in advance of self-timer shooting or a low-luminance warning.

In step S16, a flash for red-eye prevention is emitted from the discharge tube 8a via the red-eye prevention means 8f prior to emission of the flash for photography. Thereafter, in step S17, charging of the sub-capacitor 8c is started immediately. This is because the red-eye preventing flash was emitted by the charge of the sub-condenser 8c. In step S18, it is determined whether 0.75 seconds have elapsed since the emission of the red-eye prevention flash. If a negative determination is made, the process stays in step S18 until an affirmative determination is made, and if an affirmative determination is made, the process proceeds to step S19.

The 0.75 seconds is a standby time required for the human pupil to reduce to the effective red-eye prevention diameter after the emission of the red-eye prevention flash. In other words, it is the time from the emission of the red-eye prevention flash light until the pupil enters the red-eye prevention effective period in which the pupil is reduced to the red-eye prevention effective diameter.

Here, the standby time and the red-eye prevention effective period described above will be described with reference to FIG. FIG. 5 is a time chart showing a change in pupil diameter after emitting a red-eye prevention flash. The passage of time is shown along the right direction in the figure,
Pupil diameter l ₂ shows a state where the lower end is reduced showing a state in which the upper end is expanded.

In Figure 5, the pupil diameter l ₂ when the red-eye preventing flashing l ₁ is emitted is gradually reduced gradually (A point ~B point), reduced to the pupil diameter l ₂ there red-eye prevention effective diameter takes time T ₁ from the red-eye preventing flashing l ₁ is light emission in. This time T ₁ indicates a waiting time. Then, the pupil when the standby time T ₁ is passed is reduced to red-eye prevention effective diameter, more pupils continue to shrink (B point ~C point), eventually starts expanding (C point ~
D point). However, during the period immediately after the elapse of T ₂ of the standby time T ₁ is the pupil diameter l ₂ is reduced to red-eye preventing effective diameter.
The period T ₂ indicates the red-eye preventing lifetime. When passed this red-eye preventing lifetime T _2, pupil diameter l ₂ returns to the state before and widening from red-eye prevention effective diameter for emitting flash light for red-eye prevention (D point ~E point).

Now, returning to the flowchart of FIG.
In S19, it is determined whether or not the charging of the sub-capacitor 8c is completed. If the result is affirmative, the charging is stopped in step S20. If the result is negative, the process proceeds to step S21. In step S21, the fact that special flash photography is to be performed is notified by turning on or off the external LED. Further, in step S22, the shutter is opened, and in step S23, it is determined whether the flash photographing mode is the simultaneous light emission mode, the strong light emission mode, or the weak strong light emission mode.

By the way, in step S19 described above, the process proceeds to step S21 even if the charging of the sub-capacitor 8c has not been completed.
The charging of c is continued, and this charging is almost completed by the start of the emission of the photographing flash performed in the subsequent processing.

Next, a control procedure in the simultaneous light emission mode will be described based on a flowchart of FIG. When the shutter is opened in step S22 in FIG.
In step S50 of FIG.
b, 8c the discharge tube 8 via the normal light emitting means 8d
The flash for photographing is emitted only once from a, and it is determined in step S51 whether or not the exposure time has elapsed. If the determination is negative, the process remains in step S51. If the determination is affirmative, the shutter is closed in step S52.

Subsequently, in step S53, the main and sub capacitors 8
The charging of b and 8c is started, and it is determined in step S54 whether or not the charging is completed. The process remains in step S54, in which the determination is negative, and stops in step S55 when the determination is affirmative. Thereafter, the processing returns to the normal processing.

Next, a control procedure in the strong light emission mode will be described with reference to a flowchart of FIG. When the shutter is opened in step S22 of FIG.
In step S60 of FIG. 2 (c), a flash for photography is emitted from the discharge tube 8a via the multi-emission means 8e by the charged electric charge of the main capacitor 8b. In a step S61, it is determined whether or not a predetermined time has elapsed. When a negative determination is made, in a step S62, it is determined whether or not the charging of the sub-capacitor 8b is completed.
If negative in step S62, the process returns to step S61, and if positive, charging is stopped in step S63. Thereafter, the process returns to step S61. If the result in step S61 is affirmative, in step S64, the flashlight for photography is emitted from the discharge tube 8a via the multi-emission means 8e by the charge of the sub-condenser 8c. Then, in a step S65, it is determined whether or not the exposure time has elapsed. If the result is negative, the process stays in the step S65. If the result is affirmative, the shutter is closed in a step S66. In step S67, charging of the main and sub capacitors 8b and 8c is started, and in step S68, it is determined whether the charging is completed. If not, the process remains at step S68, and if yes, the charging is stopped at step S69. Thereafter, the processing returns to the normal processing.

The control procedure in the weak and strong light emission mode is as shown in the flowchart of FIG. 2D, but the flow of the loop is almost the same as that of FIG.

On the other hand, in FIG. 2 (a), if a negative determination is made in step S13, that is, if it is determined that it is not special flash photography, it is determined in step S24 whether or not a red-eye prevention mode is set. Proceed to step S28, and if affirmative, proceed to step S25. In step S25, the red-eye prevention mode is set, and the fact that the red-eye prevention flash is emitted prior to the main emission of the shooting flash is displayed on the external LCD. In step S26, the red-eye preventing flash is emitted from the discharge tube 8a via the red-eye preventing means 8f prior to the emission of the photographing flash from the discharge tube 8a. In step S27, it is determined whether 0.75 seconds have elapsed since the emission of the red-eye preventing flash. If a negative determination is made, the process stays in step S27 until an affirmative determination is made, and if an affirmative determination is made, the process proceeds to step S28. In step S28, the shutter is opened, and in step S29, main light emission is performed by the main capacitor 8e. Subsequently, in step S30, it is determined whether or not the exposure time has elapsed.
When the value remains at 0 and the result is affirmative, the process proceeds to step S31, and the shutter is closed. In step S32, charging of the main and sub capacitors 8e and 8f is started, and in step S33, it is determined whether the charging is completed. If the result is negative in step S33, the process stays in step S33. If the result is affirmative, the process proceeds to step S34 to stop charging. Thereafter, the processing returns to the normal processing.

On the other hand, if the result in step S12 is negative, that is, if it is not flash photography, the process proceeds to step S35, where the shutter is opened, and it is determined in step S36 whether the exposure time has elapsed. If not, the process remains at step S36. If affirmative, the shutter is closed at step S37. Subsequently, in step S38, the main and sub capacitors 8c and 8d
Is started, and it is determined whether or not the charging is completed in step S39. If the result is negative, the process remains in step S39, and if the result is positive, the charging is stopped in step S40. Thereafter, the processing returns to the normal processing.

As described above, in the multi-flash red-eye prevention mode, before the shutter is opened, after the red-eye prevention flash is emitted from the discharge tube 8a via the red-eye prevention means 8f by the charge of the sub-capacitor 8c, the main or sub-capacitor is released. 8b, 8c
Flash light for photography is emitted from the discharge tube 8a via the multi-emission means 8e by one of the charged charges of the above, and after a predetermined time from this emission, the other is taken again from the discharge tube 8a via the multi-emission means 8e. Flash for flash.

According to this, the capacitor for charging the electric charge for emitting the flash for preventing red-eye and the capacitor for charging the electric charge for causing the sub-light emission of the flash for shooting in the multiple flash mode are used as a single capacitor. Further, the size of the camera or the flash device is not increased, and the production cost is not increased.

Next, a second embodiment of the present invention will be described. First,
The differences between the second embodiment and the first embodiment will be briefly described. In the first embodiment described above, the red-eye prevention flash is emitted when the full-press switch SW2 is turned on, in other words, when the full-press signal is output. Was reduced to the effective red-eye prevention diameter 0.75 seconds after the emission of the red-eye prevention flash. Therefore, there is a time lag of 0.75 seconds before the shutter is released after the release button is fully depressed, so there is a possibility that the photographer may miss the shutter chance even slightly.

On the other hand, in the second embodiment, the aim is to eliminate the occurrence of a time lag by causing the flash for preventing red-eye to emit light in response to the ON of the half-press switch SW1, in other words, the output of the half-press signal.

Hereinafter, the second embodiment will be described with reference to the flowchart of FIG. Here, in describing the flowchart of FIG. 3, the description of the processing overlapping with that of FIG. 2 (a) will be omitted.

When the half-press switch SW1 is turned on in the same manner as in FIG. 2A, the program in FIG.
After performing a series of processes up to S8, it is determined in step S80 whether or not a red-eye prevention mode is set. If an affirmative result is obtained, the process proceeds to step S81, where the red-eye preventing flash is emitted from the discharge tube 8a via the red-eye preventing means 8f prior to the emission of the photographing flash. In other words, the half-press switch SW1 has been turned on in step S5 before the processing in steps S80 and S81, and the flash for preventing red-eye in the red-eye prevention mode is substantially turned on when the half-press switch SW1 is turned on. Then, light is emitted due to the half-press operation of the release button. After this, step
In S82, charging of the sub-capacitor 8c is started immediately, and in step S83, the timer starts counting time.

Subsequently, in step S9, it is determined whether or not the half-press switch SW1 is turned on. If the result is negative, the charging is stopped in step S86, and the process returns to the normal process.If the result is affirmative, the process returns to step S10. Then, it is determined whether or not the full-press switch SW2 is on. If step S10 is denied, it is determined in step S84 whether a predetermined time has elapsed. Here, the predetermined time is 0.75 seconds.
The timing of 0.75 seconds is started in step S83 described above. If step S84 is affirmed, the process proceeds to step S85, but if denied, the loop of steps S9, S10, and S84 is repeated until the result is affirmed. Then, in step S85, charging of the sub-capacitor 8c started in step S82 is stopped.

On the other hand, if step S10 is affirmative, that is, if it is determined that the full-press switch SW2 has been turned on, it is determined through step S11 whether or not shooting using the electronic flash device 8 has been performed in step S18. Here, in the second embodiment, the flash photography mode has two modes: a normal flash photography mode and a red-eye prevention mode. If step S18 is denied,
That is, when it is determined that the flash photography is not performed, the process proceeds to step S35, and a series of operations including opening of the shutter are performed. When step S12 is affirmative, that is, when it is determined that the flash photography is performed, it is further determined in step S24 whether or not the red-eye prevention mode is set. If the result is negative, the process proceeds to step S28, and a series of operations including opening of the shutter are performed. If the result is affirmative, it is determined in step S87 whether a predetermined time has elapsed. However, the predetermined time here has a different meaning from the predetermined time in step S84 described above, and the pupil is moved to the red-eye prevention effective diameter after the red-eye prevention effective period has elapsed since the red-eye prevention flash was emitted. It means the time to expand further. This time is about one second.

If step S87 is denied, it is determined in step S88 whether a predetermined time of 0.75 seconds has elapsed. If negative, step S88 is repeated until 0.75 seconds elapse, and if positive, charging of the sub-capacitor 8c is stopped in step S89.

Up to this point, in the loop of steps S24 and S87 to S89, when the half-press switch SW1 is turned on, a red-eye prevention flash is emitted, and immediately thereafter, when the full-press switch SW2 is turned on, the half-press switch SW1 is turned on, that is, Step S88 is repeatedly performed until 0.75 seconds elapse from the irradiation of the red-eye prevention flash, and the opening of the shutter is prohibited.

As described above, this is because the pupil does not reduce to the effective red-eye prevention diameter until 0.75 seconds have elapsed since the emission of the red-eye prevention flash. That is, during the standby time required for the human pupil to be reduced to the effective red-eye prevention diameter by the emission of the red-eye prevention flash, the opening of the shutter in response to the ON of the full-press switch SW2 is prohibited.

On the other hand, if the full-press switch SW2 is turned on when 0.75 seconds have elapsed since the half-press switch SW1 was turned on, step S8
8. The process proceeds to step S28 via S89, and the shutter is immediately allowed to be opened. That is, when the pupil enters the red-eye prevention effective period in which the pupil is reduced to the red-eye prevention effective diameter, the shutter is opened and the flash for photographing is emitted in response to the turning on of the full-press switch SW2.

However, the shutter is allowed to be opened after 0.75 seconds elapse, but as described above, approximately one second elapses after the emission of the red-eye prevention flash, ie, the red-eye prevention flash is activated after the red-eye prevention flash is emitted. If the period elapses and the time until the pupil expands beyond the effective red-eye prevention diameter has elapsed,
Processing different from the processing in steps S87 to S89 described above is performed.

 This processing will be described below.

First, it is determined in step S24 that the red-eye prevention mode has been set, and further in step S87, it is determined whether one second has elapsed since the emission of the red-eye prevention flash. If affirmative, step S90
Then, the red-eye preventing flash is emitted again. Thereafter, in step S91, it is determined whether 0.75 seconds have elapsed. If not, step S91 is repeatedly executed until 0.75 seconds elapse, and if affirmative, the process proceeds to step S28.

Up to this point, for the loop of steps S24, S87, S90, and S91, the flash for red-eye prevention is emitted by turning on the half-press switch SW1, and after about 1 second, the full-press switch is turned on.
When SW2 is turned on, a red-eye preventing flash is emitted again. This is because the half-press switch SW1 is turned on and the flash for red-eye prevention is emitted, and subsequently the full-press switch SW2 is turned on and then the half-press switch SW1 is turned on, that is, about one second has elapsed since the emission of the red-eye prevention flash. If done after
This is because the pupil is wider than the effective red-eye prevention diameter, and there is no red-eye prevention effect at this time.

Then, when the red-eye preventing flash is emitted again, the shutter is opened and the photographing flash is emitted after 0.75 seconds as a standby time has elapsed and the red-eye preventing effective period has entered.

As described above, when the red-eye prevention mode is selected by the selection means 9, a red-eye prevention flash is emitted from the discharge tube 8a via the red-eye prevention means 8f in response to the output of the half-press signal from the switch SW1. You. Then, during a standby time required for the pupil of the subject to be reduced to the red-eye prevention effective diameter by emission of the red-eye prevention flash, the shutter 7 according to the output of the full-press signal is provided.
When the pupil enters a red-eye prevention effective period in which the pupil is reduced to the red-eye prevention effective diameter, the shutter 7 is opened in response to the output of the full-press signal and the flash for photographing is emitted to enable the red-eye prevention. After the period elapses and the pupil expands beyond the red-eye prevention effective diameter, the flash for preventing red-eye is emitted again according to the output of the full-press signal, and the shutter 7 is opened after the standby time has elapsed and the red-eye prevention effective period has been entered. Release the flash for shooting.

According to this, the flash for preventing red-eye is emitted when the half-press switch SW1 is turned on instead of the full-press switch SW2, so that the occurrence of a time lag is reduced, and a photo opportunity is not missed.

On the other hand, after the red-eye prevention
When the switch SW2 is turned on, the flash for red-eye prevention is emitted again when the switch SW2 is turned on. The shutter 7 is opened and the flash for photographing is emitted after the standby time has elapsed and the red-eye prevention effective period has been entered.

Only in this case, the flash for preventing red-eye
Since the light is emitted when the switch SW2 is turned on, a time lag occurs, but red-eye prevention measures for the subject are surely taken.

Further, a third embodiment of the present invention will be described. In the third embodiment, when performing flash photography when the subject is at a short distance, in either the normal flash photography mode or the red-eye prevention mode, the photography flash is generated by the charge of the sub-capacitor. Flash. this is,
This is because, when the subject is at a short distance, if the flash for photographing is emitted by the charge of the main capacitor, overexposure is caused.

Hereinafter, the third embodiment will be described with reference to the flowchart of FIG. However, the description of the processes that are the same as those in FIGS. 2A and 3 will be omitted.

As shown in the flowchart of FIG. 4, when the shutter is opened in step S28, the process proceeds to step S10, and it is determined whether the distance to the subject is equal to or less than a predetermined distance (for example, 1 m). This is determined by whether or not a short distance signal has been output from the distance measuring means 2. If step S100 is denied, that is, if it is determined that the subject distance is not less than 1 m, the flash for photographing is emitted by the charge of the main capacitor 8b in step S101.

On the other hand, if step S100 is affirmed, that is, if it is determined that the subject distance is within 1 m, the flash for photography is emitted by the charge of the sub-condenser 8c in step S102.

For example, in the red-eye prevention mode, the red-eye prevention flash is emitted by the charge of the sub-condenser 8c as described above.
When a short-range signal is output from, the flash for photographing is also emitted by the charge of the sub-condenser 8c.

Here, the flash for photography is emitted 0.75 seconds after the emission of the red-eye prevention flash, and each of the red-eye prevention flash and the flash for photography is emitted by the charge of the sub-condenser 8c. After 0.75 seconds, charging is completed. Therefore, the emission of the photographing flash is not delayed due to the incomplete charging of the sub-condenser 8c.

As described above, according to the third embodiment, when the short-distance signal is output from the distance measuring unit 2, regardless of which of the normal flash photography mode and the red-eye prevention mode is selected by the selection unit 9, The flash for photographing is emitted by the charge of the sub-condenser 8c. Therefore, even when the subject is in close proximity, a photograph that would be overexposed is not taken.

In the third embodiment, the photographing flash is emitted by the charge of the sub-condenser 8c based on the output of the short-distance signal from the distance measuring means 2. However, the photographing flash is emitted by the main capacitor 8b and the sub-capacitor 8c. It is also possible to make it possible to arbitrarily select which of the two types of light is to be emitted according to the photographer's intention. In this case, it is possible to change the light emission amount of the photographing flash depending on the photographing situation.

In the above-described second and third embodiments, either the normal flash photographing mode or the red-eye prevention mode can be selected by the selection means. However, the present invention is not limited to this. It is also conceivable to add a light emission mode.

According to the first and second aspects of the present invention, when the multi-flash red-eye prevention mode is selected by the selection unit, the charge of the sub-capacitor is charged through the red-eye prevention unit before the shutter is opened. A red-eye preventing flash is emitted from the discharge tube. Subsequently, a flash for photographing is emitted from the discharge tube via the multi-emission means by one of the charged charges of the main or sub-condenser, and after a predetermined time from this emission, the other is discharged by the discharge tube via the multi-emission means. Flash light is emitted from the camera.

According to this, the capacitor for charging the electric charge for irradiating the flash for red-eye prevention and the capacitor for charging the electric charge for multi-emission are used as a single capacitor, so that the size of the camera or the flash device is increased. Also, there is no increase in manufacturing cost.

According to the third and fourth aspects of the present invention, when the red-eye prevention mode is selected by the selection unit, the red-eye prevention mode is performed from the discharge tube via the red-eye prevention unit in accordance with the output of the first operation signal from the signal output unit. Flash light is emitted. Then, during a standby time required for the pupil of the subject to be reduced to the red-eye prevention effective diameter by the emission of the red-eye prevention flash, the opening of the shutter according to the output of the second operation signal is prohibited. When the red-eye prevention effective diameter period, which has been reduced to the effective prevention diameter, enters the shutter in response to the output of the second operation signal and emits a flash for photographing, and after the red-eye prevention effective period elapses, the pupil becomes effective. After the opening is larger than the diameter, the opening of the shutter according to the output of the second operation signal is prohibited again.

According to this, the flash for preventing red-eye is emitted not according to the output of the second operation signal from the signal output means but according to the output of the first operation signal.
Never miss a photo opportunity.

According to the fifth aspect of the present invention, when the short distance signal is output from the distance measuring means, the charge of the sub-capacitor is charged regardless of which of the normal flash photographing mode and the red-eye prevention mode is selected by the selecting means. Flash light for photography is emitted. Therefore, even when the subject is in close proximity, a photograph that would be overexposed is not taken.

[Brief description of the drawings]

FIG. 1 is a block diagram showing the configuration of a camera with a built-in electronic flash device according to the present invention. FIGS. 2 (a) to 2 (d) are flowcharts showing control procedures of the first embodiment, and FIG. FIG. 4 is a flowchart showing a control procedure of the second embodiment, and FIG. 4 is a flowchart showing a control procedure of the third embodiment. FIG. 5 is a time chart showing a change in pupil diameter after emitting a red-eye preventing flash. (Explanation of reference numerals of main parts) 1... CPU 2... Distance measuring circuit 3... Photometric circuit 4... Exposure control circuit 5... Motor drive circuit 8. 8b: Main capacitor, 8c: Sub capacitor 8d: Normal light emitting means, 8e: Multi light emitting means 8f: Red eye prevention means, 8g: Charging circuit 8h: Light emitting control circuit SW _1: Half-press switch, SW ₂ …… Full push switch

Continuing from the front page (72) Inventor Daiki Tsukahara 1-6-3 Nishioi, Shinagawa-ku, Tokyo Co., Ltd. Inside Nikon Oi Works (72) Inventor Kiyosada Machida 1-6-3 Nishioi, Shinagawa-ku, Tokyo, Japan Inside Nikon Oi Works, Ltd. (72) Inventor Minoru Kato 1-6-3, Nishioi, Shinagawa-ku, Tokyo Stock Company Nikon Oi Works (72) Tokuyasu Kotani, 1-3-6, Nishioi, Shinagawa-ku, Tokyo Stock Company Nihon Oi Plant (58) Fields surveyed (Int. Cl. ⁶ , DB name) G03B 15/05

Claims (5)

(57) [Claims] 1. A shutter, a discharge tube that emits flash light to a subject, a main capacitor that is charged with electric charge for causing the discharge tube to emit light, and a sub-capacitor that is charged with an electric charge for causing the discharge tube to emit light. Energizing light-emitting means for emitting a flash for photography only once from the discharge tube while the shutter is open; and emitting a plurality of flashes for photography from the discharge tube several times while the shutter is open. Multi-emission means, red-eye prevention means for emitting red-eye prevention flash from the discharge tube to reduce the pupil of the subject prior to opening of the shutter, normal flash photography mode, multi-flash photography mode, and red-eye prevention mode Selecting means for selecting any of the above, and control means for selectively controlling the normal light emitting means, the multiple light emitting means, and the red-eye preventing means in accordance with the output of the selecting means. When the normal flash photography mode is selected by the selection means, the control means only once flashes the photography flash light from the discharge tube through the normal light emission means by the charge of the main capacitor. When the multi-flash photography mode is selected by the selection unit,
The flashlight for photography is emitted from the discharge tube via the multi-emission means by one of the charged charges of the sub-capacitor, and the discharge tube is emitted by the other via the multi-emission means at a predetermined time after the emission. When the red-eye prevention mode is selected by the selection unit, the red-eye prevention flash is emitted from the discharge tube via the red-eye prevention unit by the charge of the sub-capacitor when the red-eye prevention mode is selected by the selection unit. A camera with a built-in electronic flash device, wherein the flash for photographing is emitted only once from the discharge tube via the normal light emitting means by the charge of the main capacitor. 2. The multi-flash red-eye prevention mode can be selected by the selection means. When the multi-flash red-eye prevention mode is selected, the control means controls the red-eye prevention by charging the sub-capacitor. After emitting the red-eye prevention flash from the discharge tube through the means, the main body and the sub-capacitor cause the photographing flash to be emitted from the discharge tube through the multi-emission means by one of the charged charges. 2. The electronic flash device built-in camera according to claim 1, wherein the flash for photographing is emitted from the discharge tube via the multi-emission means by a predetermined time after the emission. . 3. The first operation of the release operation member causes a first operation.
A signal output means for outputting an operation signal and outputting a second operation signal by a second operation following the first operation; a shutter; a discharge tube for emitting a flash of light to a subject; A normal light emitting means for emitting light from the discharge tube, a red-eye preventing means for emitting red-eye preventing flash light from the discharge tube for reducing a pupil of a subject prior to opening of the shutter, and a normal flash photography mode. Selecting means for selecting one of the red-eye prevention modes; and control means for selectively controlling the normal light-emitting means and the red-eye preventing means in accordance with an output of the selecting means. When the normal flash photography mode is selected by the selection means, the shutter is opened and the photography flash is emitted in response to the output of the second operation signal, and the red light is emitted by the selection means. When the eye prevention mode is selected, the red-eye prevention flash is emitted in response to the output of the first operation signal, and the emission causes the pupil of the subject to be reduced to a red-eye prevention effective diameter. During the period, the opening of the shutter according to the output of the second operation signal is prohibited, and thereafter, when the pupil enters a red-eye prevention effective period in which the pupil is reduced to the red-eye prevention effective diameter, the output of the second operation signal is performed. In response to the output of the second operation signal after the red-eye prevention effective period has elapsed and the pupil has expanded beyond the red-eye prevention effective diameter. A camera with a built-in electronic flash device, wherein opening of the shutter is prohibited again. 4. When the second operation signal is output after the red-eye prevention effective period due to the emission of the red-eye prevention flash has elapsed, the control means re-executes the red-eye prevention flash according to the output. 4. The electronic flash according to claim 3, wherein the shutter is opened and the flash for photographing is emitted after the standby period has elapsed and the red-eye prevention effective period has elapsed. Built-in camera. 5. A shutter, a discharge tube for emitting a flash of light to a subject, a main capacitor charged with an electric charge for causing the discharge tube to emit light, and an electric charge for causing the discharge tube to emit light and having a charge capacity. A sub-capacitor smaller than the charging capacity of the main capacitor; a normal light emitting means for emitting a flash for photographing from the discharge tube during opening of the shutter; and a red-eye prevention for reducing a pupil of a subject prior to opening of the shutter. Red-eye prevention means for emitting flash for use from the discharge tube, distance measurement means for outputting a short-distance signal when the distance to the subject is detected to be less than or equal to a predetermined value, and any one of a normal flash photography mode and a red-eye prevention mode. Selecting means for selecting the control means, control means for selectively controlling the normal light emitting means and the red-eye prevention means in accordance with the output of the selecting means, When the normal flash photography mode is selected by the selection means, the flash for photography is emitted by the charge of the main capacitor, and when the red-eye prevention mode is selected by the selection means, the charge of the sub-capacitor is charged. After the flash for red-eye prevention is emitted by the above, the flash for photographing is emitted by the charge of the main capacitor. When the short-distance signal is output from the distance measuring means, the normal flash is selected by the selecting means. Whichever of the shooting mode and the red-eye prevention mode is selected,
A camera with a built-in electronic flash device, wherein the flash for photography is emitted by the charge of the sub-capacitor.