JPH04310933A - Controller and method for red-eye prevention - Google Patents

Abstract

PURPOSE:To prevent a person as a subject from having an unnatural expression or closing his eyes as a result of preliminary irradiation by irradiating the subject with a constant quantity of light preliminarily irrelevantly to the setting of the focal length of a lens even when the irradiation angle of the light emission part of a stroboscopic device is varied with the focal length of the lens. CONSTITUTION:When the subject is irradiated preliminarily for red-eye prevention, an (f) value control means 7 controls the irradiation angle control means 3 of the stroboscopic device 1 according to focal length information on the lens obtained by the switching operation of an (f) value changeover switch 10, and consequently the irradiation angle of the light emission part 2 of the stroboscopic device 1 is controlled. At the same time, a light emission time control means 6 determines the light emission time, period, and frequency of the preliminary irradiation according to an (f) value controlled by the (f) value control means 7 to control a red-eye prevention light emission control means 4, and then the light emission part 2 irradiates the subject preliminarily with a constant quantity of light irrelevantly to the lens focal length.

Description

[Detailed description of the invention]

0001

TECHNICAL FIELD The present invention relates to a red-eye prevention control device and a red-eye prevention method, and more particularly, the present invention relates to a red-eye prevention control device and a red-eye prevention method, and more particularly, the present invention is capable of changing the illumination angle of a light emitting part of a strobe device according to the focal length of a lens, and Related to a red-eye prevention control device and a red-eye prevention method that ensure that the amount of light irradiated onto the subject is constant when preliminary irradiation is performed on the subject in order to shrink the subject's pupils prior to photography. It is.

0002

2. Description of the Related Art When a color photograph of a person is taken under low illumination using flash light, a so-called red-eye phenomenon often occurs in which the pupil of the human eye becomes red. This red eye phenomenon occurs when the flash of light from a light emitting device passes through the pupil of the eye and is reflected by the retina, and the reflected light is captured on film.

[0003] Regarding the method for preventing such red-eye phenomenon,
For example, there is a discussion article on page 250 of the May 1989 issue of Shashin Kogyo, and the first method is to move the flash away from the optical axis using an adapter.

[0004] The second method is, ``If you brighten the eyes once, the pupils will not open easily.
"You can light a match in front of your eyes before taking a photo," or "Please look at the light bulb for a moment."
etc. is stated. All of these act to make the pupil smaller before photographing.

On the other hand, Japanese Patent Publication No. 58-48088 discloses that before irradiating a flash for photographing, a lamp is turned on for preliminary irradiation for the time necessary for the human pupil to close. A method for preventing red eye in flash photography is described in which the preliminary irradiation causes the pupil to be closed and then the flash light is used for photography.

Furthermore, Japanese Patent Laid-Open No. 1-244437 discloses that under conditions where red-eye occurs, a red-eye prevention illumination light is emitted before the main flash device for illuminating the subject emits light, and this red-eye prevention A red-eye prevention control device configured to control the amount of red-eye prevention irradiation light emitted according to the distance to the object so that the amount of irradiation light on the object remains approximately constant regardless of the distance to the object. is listed.

[0007]

[Problems to be Solved by the Invention] The first method for preventing red eye described in the photographic industry is to connect the light emitting part and the photographing lens via an adapter in order to increase the included angle between the light emitting part, the subject, and the photographing lens. increasing the distance between them.

However, in this case, considering the size of the camera, it is difficult to sufficiently increase the distance between the light emitting section and the photographing lens. This difficulty is particularly noticeable in cameras with built-in strobes.

[0009] Also, as in the second method for preventing red eyes,
Lighting a match or looking at a light bulb before taking a picture can be very cumbersome and sometimes impractical.

The device described in Japanese Patent Publication No. 58-48088 requires a lamp for preliminary irradiation in addition to the means for emitting flash light for photographing, resulting in problems of increased cost and increased space. be.

Furthermore, the method described in Japanese Patent Application Laid-Open No. 1-244437 provides a constant amount of light to the subject regardless of the shooting distance as an improvement to the preliminary irradiation control performed before photographing. The subject may not always be at the distance information obtained, and this is especially likely when photographing multiple people. For example, if the amount of preliminary illumination is controlled to be constant for a long distance, People looking at it from a close distance will feel extremely dazzled.

On the other hand, if the amount of preliminary irradiation is controlled to be constant for short distances, a new problem arises in that the effect is insufficient for people viewing from a distance. Additionally, even if the subject is slightly out of focus, the red-eye phenomenon can be seen.

[0013] Therefore, the amount of light for preliminary irradiation is preferably kept at a constant value so that a stable effect can be obtained within a certain distance. In recent years, many cameras with variable focal lengths (f-number) have come out, but some of these are configured so that the strobe firing angle can be narrowed to match the f-number of the lens. , the guide number increases,
The opposite is true on the short focal length side. As a result, the amount of light for preliminary irradiation is reduced to f
Since it changes depending on the value, the red-eye prevention effect and glare will change.

[0014] The first object of the present invention was made in view of the above-mentioned circumstances, and its purpose is to obtain a stable red-eye prevention effect and to improve the facial expression of the subject by providing more light than necessary. To provide a red-eye prevention control device capable of preventing blindness due to unnaturalness and glare.

A second object of the present invention is to provide a red-eye prevention control device that can easily control the amount of light irradiated during preliminary irradiation and realize stable light emission.

Furthermore, the third aspect of the present invention is a red-eye prevention system that can control the amount of preliminary irradiation light to be constant, always give optimal light stimulation to the subject, and stably perform red-eye prevention. The purpose is to provide a method.

[0017]

[Means for Solving the Problems] In order to achieve the first object, the invention of claim 1 provides a light emitting section that can change the irradiation angle in conjunction with the focal length of the lens, and a light emitting section that can change the illumination angle in conjunction with the focal length of the lens, a red-eye prevention light emission control means for causing the light emitting unit to perform preliminary irradiation on the subject in order to reduce the amount of light emitted from the light emitting unit; a light amount that controls the red-eye prevention light emission control means in accordance with the focal position information of the lens so that the irradiation angle is changed and controlled and the intensity of the irradiation light of the preliminary irradiation is substantially constant regardless of the setting of the focal length of the lens; The present invention is characterized by comprising a control means.

[0018] Furthermore, in order to achieve the second object, the invention according to claim 2 is characterized in that the light amount control means is configured to control at least one of the light emission time and the light emission repetition time. It is something.

Furthermore, in order to achieve the third object, the irradiation angle of the light emitting part of the strobe device is changed and controlled by the light amount control means in conjunction with the change in the focal length of the lens, The amount of light used for pre-irradiation to shrink the pupil of the subject is calculated by a light amount control means so that it is constant regardless of the focal length of the lens, and the pre-irradiation is applied to the subject with the amount of light based on the calculation result. The invention is characterized in that the light emitting section is controlled so as to perform the following steps.

[0020]

[Operation] The light emitting part of the strobe device in the red-eye prevention control device configured as above constricts the pupil of the subject before taking a picture while changing the irradiation angle in conjunction with the focal length of the lens. Therefore, the red-eye emission control means controls the light emitting section to perform preliminary irradiation on the subject. During this preliminary illumination, the red-eye prevention light emission control means is controlled by the light amount control means so that the illumination intensity to the subject remains constant regardless of the setting of the focal length of the lens, and the optimal preliminary illumination is performed on the subject. It makes it possible.

[0021] Furthermore, when controlling the preliminary irradiation intensity for the red-eye prevention light emission control means by the light amount control means,
By controlling at least one of the light emission time and the light emission repetition time, the subject is irradiated with a constant irradiation intensity regardless of the focal position information of the lens.

Furthermore, in order to change the irradiation angle of the light emitting part of the strobe device in conjunction with the focal length of the lens, and to shrink the pupil of the subject before photographing, the light emitting part is controlled by the red-eye prevention light emission control means. When performing preliminary irradiation on the subject by controlling Based on this, the light emitting unit is controlled to preliminarily irradiate the subject with a constant amount of light regardless of the focal length of the lens, thereby preventing red eye.

[0023]

Embodiments Hereinafter, embodiments of the present invention will be explained in detail with reference to the drawings. FIG. 1 is a block diagram showing the configuration of a red-eye prevention control device according to the present invention.

In FIG. 1, reference numeral 1 denotes a strobe device, which is detachably attached to a hot shoe of a camera body (not shown) or built into the camera body. This strobe device 1 includes a light emitting section 2, an illumination angle control means 3, and a red-eye prevention light emission control means 4.

The illumination angle of the light emitting section 2 can be changed by the illumination angle control means 3 in conjunction with the focal length of the lens. The illumination angle control means 3 includes a light amount control means 5
The irradiation angle of the light emitting section 2 is varied based on a command from the f-value control means 7 included in the control means 7.

The light amount control means 5 is a central processing unit (CPU) including a light emission time control means 6 and the f-value control means 7. The light emitting time control means 6 in the light amount control means 5 sets the focal length of the lens so that the intensity of the irradiation light preliminarily irradiated from the light emitting unit 2 to the subject value is set in order to prevent red eyes of the subject (not shown). The red-eye prevention light emission control means 4 is controlled in accordance with the lens focal position information so that the subject illuminance is approximately constant regardless of the focal length, although it changes depending on the value. .

That is, the light emitting time control means 6 outputs data on either the light emitting time or the light emitting repetition time to the red eye prevention light emitting control means 4 in accordance with the f value information from the f value control means 7. . This red-eye prevention light emission control means 4
is configured to control the light emitting unit 2 to emit irradiation light for preliminary irradiation.

For example, as described above, the irradiation angle of the light emitting section 2 changes depending on whether the lens is on the tele (telephoto) side or the wide (wide angle) side. In order to avoid this, the intensity of the preliminary illumination that is emitted from the light emitting unit 2 to the subject changes, regardless of whether it is on the telephoto side or the wide side. The light emission time control means 6 of the light quantity control means 5 controls the red-eye prevention light emission control means 4 so that the light emission time is constant at the subject position.

Further, the f-number control means 7 is connected to a wide terminal 10W, a tele terminal 10T, and a movable terminal 10C of the f-number changeover switch 10. By switching the movable terminal 10C to the telephoto terminal 10T side or the wide terminal 10W side, lens focal position information, that is, f-number information is input to the f-number control means 7.

[0030] In response to the input of this f-number information, the f-number control means 7 controls the lens drive circuit 8, so that the lens drive circuit 8 moves the lens 9 toward the telephoto side or the wide side. .

The operation of this embodiment configured as described above will be explained with reference to the time chart of FIG. 2 as appropriate. First, when the f-number changeover switch 10 is operated by the photographer, the movable terminal 10C changes to the tele side terminal 10T.
Alternatively, when it is switched to either the wide terminal 10W, the f-number control means 7 in the light amount control means 5 determines whether the movable terminal 10C of the f-number changeover switch 10 is operated to the tele terminal 10T or the wide terminal 10W. The f-number control means 7 controls the lens drive circuit 8 according to the determination result.

Thereby, the lens drive circuit 8 drives the lens 9 based on the f-number information on the tele terminal 10T side or the wide terminal 10W side which is switched by the movable terminal 10C of the f-number changeover switch 10.

At the same time, the f-number control means 7 also provides an operation signal to the illumination angle control means 3 in response to the switching of the f-number changeover switch 10. Based on this operation signal, the illumination angle control means 3 drives the light emitting unit 2 to emit light so that a light distribution surface having a predetermined illumination angle, that is, an illumination angle corresponding to the focal length of the lens is obtained. Move the tube, the reflector (both not shown), or both.

Next, when the photographer presses the release button (not shown) halfway to take a picture and a release signal is given to the light amount control means 5, the light emission time control means 6 in the light amount control means 5 is activated. The light emitting time, period, and rotation speed of preliminary irradiation for preventing red-eye are determined in accordance with the controlled f value.

A light emission control signal based on the determination of the light emission time, period, and number of times is outputted from the light emission time control means 6 to the red-eye prevention light emission control means 4. In accordance with this light emission control signal, the red-eye prevention light emission control means 4 controls the light emission of the light emitting unit 2, and performs preliminary red-eye irradiation on the subject.

This preliminary irradiation is carried out by the light emission time control means 6.
Since the light is emitted for the light emission time, period, and number of times determined by , the subject's pupils are closed. Then,
Normal strobe shooting operation will occur. That is, when the release button is pressed two steps, the shutter (not shown) opens,
In synchronization with this, the light emitting unit 2 of the strobe device 1 emits flash light, and the subject is photographed.

The light emission by the light emitting section 2 at this time is also controlled by the light emission time control means 6, which determines the light emission time and timing and provides a light emission control signal to the red eye prevention light emission control means 4. The light emitting section 2 is caused to emit light.

Next, f controlled by the f value control means 7
The light emission control for performing the preliminary irradiation according to the value will be explained in detail with reference to the timing chart of FIG. 2.

A timing chart of control when the f value is f1, which is the widest side, is shown in the part (a) in FIG. In (a) of FIG. 2, tA1 is the light emission time per preliminary irradiation (light emission time for guide number 1 to 2), tB1 is the repetition time of preliminary irradiation, and tWAIT is the light emission time per preliminary irradiation. This is the time from the start of irradiation to the main light emission, which is light emission for photographing, and is approximately 1 second longer than the human pupil contraction time. Further, n indicates the number of preliminary irradiations.

[0040] Also, the f value is f2 (f1<f
When set to 2) and the strobe firing angle is narrowed down,
If the control is the same as the f1 value, the guide number per shot will be large, so the control is changed as shown in FIG. 2(b).

In FIG. 2(b), tA2 indicates the light emission time per one preliminary irradiation, tA1>tA2, and tB1, n, and tWAIT are the same as in FIG. 2(a). Now, the preliminary irradiation light amount to be irradiated to the subject is set to f1 and f
It can be made almost the same as in case 2. f value is f1
and f2, the irradiation time also takes a value intermediate between tA1 and tA2.

Furthermore, (c) in FIG. 2 shows an example when changing from f1 to f2 value, and (c) in FIG.
, tA1 is the luminescence time per preliminary irradiation,
This is the same as in FIG. 2(a), but by setting tB1<tB2, the total amount of preliminary irradiation or the amount of preliminary irradiation light per unit time is made the same as in FIG. 2(b). In this case, the number of times of light emission becomes n>m, and the number of times of light emission decreases.

In both cases of FIG. 2(b) and FIG. 2(c) above, red eye can be prevented when changing from f1 to f2, but experimentally, FIG. 2(b) It has been found that the same visual appearance when switching from f1 to f2 can be achieved by controlling as follows.

However, if it is difficult to change the irradiation time or the light emission time tA2 becomes too short and stable light emission becomes difficult, the operation shown in FIG. 2(c) or the procedure shown in FIG. The configuration may be such that the combination of (b) and (c) in FIG. 2 is used, that is, the values of both the light emission times tA1 and tB1 are changed in combination.

As described above, according to this embodiment, in order to shrink the pupil of the subject prior to photographing, the light amount control means 5 controls the illumination of the light emitting section 2 of the strobe device 1 in conjunction with the focal length of the lens. In addition to controlling the angle to change, the lens focal length information is controlled so that the intensity of the pre-irradiation light for red-eye prevention is almost constant for the subject, regardless of the lens focal length setting. Accordingly, the red-eye prevention light emission control means 4 is controlled by the light quantity control means 5, and the red-eye prevention light emission control means 4 performs preliminary irradiation from the light emitting unit 2. The amount of irradiated light can be changed so that the amount of irradiated light remains almost constant regardless of the irradiation angle that changes depending on the lens focal length, and a stable red-eye prevention effect can be obtained.

Therefore, the above embodiment has the advantage that it is possible to prevent the subject from looking unnatural or from closing his or her eyes due to dazzling caused by performing preliminary irradiation on the subject more than necessary.

It should be noted that the present invention is not limited to the above-mentioned embodiments, but can be implemented in various modifications without departing from the gist thereof.

For example, in the above embodiment, preliminary irradiation is performed multiple times, but this may be done at least once; experimentally, it has been found that performing preliminary irradiation multiple times results in less variation and better results. It has been found that a small pupil diameter is obtained.

Further, in the above embodiment, the light emission for photographing is started in relation to the preliminary irradiation, but the light emission may be controlled by an X contact or the like as in the conventional case.

Furthermore, in the above embodiment, the case where the lens 9 and the light emitting section 2 are controlled separately by the light amount control means 5 was exemplified, but in a camera with a built-in strobe, the lens 9 and the light emitting section 2 are connected by an interlocking mechanism. Alternatively, the states of the lens 9 and the light emitting section 2 (where they are currently set) may be fed back to the light amount control means 5 by an electrical signal (not shown).

Note that the amount of light emitted in the preliminary irradiation also changes depending on the voltage of the main capacitor of the strobe at the start of light emission, so if the light emission time, cycle, etc. are determined in consideration of this, a more stable light amount can be obtained.

[0052]

As described in detail above, according to the invention of claim 1, when performing preliminary irradiation to prevent red-eye of a subject, the light amount control means is used to control the amount of light in conjunction with the change in the focal length of the lens. In addition to changing the irradiation angle of the light emitting unit, the red-eye prevention light emission control means is controlled according to the lens focal length information so that the intensity of the preliminary irradiation on the subject is constant regardless of the lens focal length setting. Since the configuration is configured to perform irradiation, a stable red-eye prevention effect can be obtained, and there is no need to apply more pre-irradiation light to the subject than necessary, which may cause the subject to look unnatural due to dazzle, or to prevent the subject from closing his or her eyes. It is possible to provide a red-eye prevention control device that can effectively prevent red-eye from occurring.

Further, according to the second aspect of the invention, since the light amount control means is configured to make at least one of the light emission time and the light emission repetition time variable, delicate variable control of the light amount for preliminary irradiation is possible. This makes it possible to provide a red-eye prevention control device that can provide more stable light emission.

Furthermore, according to the invention of claim 3, when reducing the pupil of the subject to prevent red eye, the illumination angle of the light emitting section is changed according to the focal length of the lens, and the focal length of the lens is changed. Since the preliminary irradiation is performed so that the intensity of the preliminary irradiation to the subject for red-eye prevention is constant regardless of the settings, a stable red-eye prevention effect can be obtained as in the invention of claim 1, and It is possible to provide a red-eye prevention method that eliminates the need to apply an excessive amount of preliminary irradiation light, and prevents subjects from having unnatural facial expressions or closing their eyes due to dazzle.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the overall configuration of an embodiment of a red-eye prevention control device according to the present invention.

FIG. 2 is a timing chart for explaining the operation of the red-eye prevention control device shown in FIG. 1;

[Explanation of symbols]

1 Strobe device 2 Light emitting part 3 Irradiation angle control means 4　Red-eye prevention light emission control means 5 Light amount control means 6 Light emission time control means 7 f value control means 8 Lens drive circuit 9 Lens 10 f value change switch 10T Tele terminal 10W wide terminal 10C Movable terminal

Claims (3)

[Claims] 1. A light emitting unit whose illumination angle can be changed in conjunction with the focal length of a lens, and a red-eye prevention light emitting unit that causes the light emitting unit to pre-irradiate the subject in order to shrink the subject's pupil prior to photographing. a strobe device having a control means; when performing the preliminary irradiation, the irradiation angle of the light emitting section is changed and controlled according to the focal length of the lens, and the intensity of the irradiated light to the subject of the preliminary irradiation is adjusted to the focal length of the lens; and a red-eye prevention control device for controlling the red-eye prevention light emission control device in accordance with the focal position information of the lens so that the amount of light remains substantially constant regardless of the settings of the red-eye prevention control device. 2. The red-eye prevention control device according to claim 1, wherein the light amount control means controls at least one of a light emission time and a light emission repetition time. 3. The illumination angle of the light emitting part of the strobe device is changed and controlled by a light amount control means in conjunction with a change in the focal length of the lens, and the amount of light for preliminary irradiation to shrink the pupil of the subject prior to photography is adjusted. A method for preventing red eye, characterized in that the light emitting unit is controlled to perform the preliminary irradiation on the subject with the light amount based on the light amount based on the calculation result, by calculating the light amount so that the light amount is constant regardless of the focal length of the lens. .