JPH09179171A - Irradiation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an irradiation device variable in irradiation state and excellent in irradiation efficiency without making constitution large by providing a means distributing light with specified light distribution characteristic and a varying means for changing a light projecting direction. SOLUTION: In the case state of a camera, a cover member 3 is rotated by about 180 deg. centering a hinge part 4 from a non-use state and held and fixed in such a state. Irradiation angle varying operation is performed by turning a reflector 9 centering a flash light emitting tube 8. When a focal distance is long (at the time of coping with telephotographing), a subject is large in size and a state where a red-eye gets conspicuous occurs. Then, when the focal distance is long, the light is efficiency condensed by using a panel part upper than a light emission center part. Namely, the reflector 9 is faced upward by a specified angle, and direct light from the tube 8 and the reflected light from the reflector 9 are mostly made incident on a fine prism part 7b provided at the upper part of an optical panel 7, and emitted from the panel 7 in a condensed state after the direction of the light is changed to a nearly fixed direction by total reflection.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lighting device used for photography and the like.

[0002]

2. Description of the Related Art Conventionally, a lighting device for photographing has been disclosed in Japanese Unexamined Patent Application Publication No. Hei 2 (1999) -2.
As described in Japanese Patent Publication No. 166431,
It has been proposed to change the irradiation angle by moving a condenser lens arranged in front of the light emitting unit in the optical axis direction of the light beam with the change of the focal length.

[0003]

However, in the above-mentioned conventional apparatus, since the focusing state is controlled by moving the focusing lens in the optical axis direction of the light beam, the moving area of the focusing lens in the optical axis direction is controlled. Therefore, there is a disadvantage that the size becomes large in the optical axis direction.

Further, in the structure of the above-mentioned conventional device, since the light emitting portion and the optical panel are separated from each other, another object is interposed between the light emitting portion and the optical panel so that light is blocked or external force is applied to the light emitting portion and the optical panel. However, there is a drawback that the light distribution characteristics may not be obtained in some cases.

Further, recent cameras tend to have smaller zooms, and particularly in high-power zoom models, the maximum aperture value (F
_NO ) becomes darker and artificial lighting (stroboscopic light emission) tends to be used more frequently. Further, due to the miniaturization, the optical axis of the taking lens barrel and the optical axis of strobe light are close to each other, and the red-eye phenomenon is likely to occur.

Further, in order to prevent the red-eye phenomenon, it is desirable that the photographing optical axis and the optical axis of flash light emission be separated.
On the other hand, conversely, it becomes necessary to widen the irradiation range depending on the subject distance as the amount of deviation of the optical axis increases. That is, the irradiation range required differs depending on whether the subject is at a close range or at a long range, and ideally it is desirable that the emission optical axis and the photographing optical axis match at the subject position.

Therefore, in the conventional flash light emitting device, in consideration of this point, the photographing optical axis and the flash light emitting optical axis coincide with each other at a working distance substantially at the center thereof so that the object can cover both the close range and the long range. Was configured. However, such a configuration actually causes energy loss by irradiating light to unnecessary portions.

(Object of the Invention) The present invention has been made in view of the above-mentioned circumstances, and provides an irradiation device in which the irradiation state is variable and the irradiation efficiency is high without increasing the size of the structure. Is what you are trying to do.

[0009]

In order to achieve the above object of the present invention, a light projecting means for projecting light and a light distribution for distributing light from the light projecting means with a predetermined light distribution characteristic. The irradiation device includes a light unit and a changing unit for changing the light projecting direction of the light projecting unit with respect to the light distributing unit.

Further, according to the present invention, a first light distribution section that distributes light with a first light distribution characteristic, and the first light distribution section is integrally provided, and the light is distributed to the first light distribution section. The irradiation device has a second light distribution unit that distributes light with a second light distribution property different from the light property, and a selection unit that selects the first and second light distribution units.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION

(First Embodiment) FIG. 1 is a perspective view showing the outline of the configuration of a camera according to the first embodiment of the present invention. In FIG. 1, 1 is a camera body for taking a photograph, 2 is a taking lens barrel, Reference numeral 3 denotes a lid member which has a flash light emitting portion built therein and is rotatable around hinges 4 and 4 ', and also functions as a barrier of the taking lens barrel when the camera is not used. 5 and 5'automatic distance measurement (hereinafter AF
The light projecting / receiving window 6 for) is a finder window.

Further, the inside of the lid member 4 has a built-in flash light emitting portion composed of an optical panel 7, a flash light emitting tube 8 and a reflector 9 which face the subject side in a camera photographing state.

Next, the structure around the flash light emitting portion of FIG. 1 will be described in more detail with reference to FIGS. 2 is a front view of the camera, FIG. 3 is a cross-sectional view passing through the center of the flash tube 8, and FIGS. 4 and 5 are side views of the camera. The longitudinal section of the flash light emission part which passes along the center is shown. In the figure, 10 and 10 'are reflecting members arranged on the back surface side of the light emitting portion of the lid member 3, and the flash light emitting tube 8
The light emitted from is reflected to the optical panel 7 side.

As shown in the figure, the flash tube 8 is horizontally arranged substantially at the center of the optical panel 7. A vertical Fresnel lens 7a is formed on the object-side surface of the optical panel 7 (see FIG. 3) to collect light rays, and the light from the flash tube 8 is totally reflected on the light-emitting portion side on the back surface. A plurality of fine prism surfaces 76 for changing the direction are formed in parallel with the flash light emitting tube 8 at upper and lower positions of the flash light emitting tube 8.

In this embodiment, the positions of the optical panel 7 and the flash tube 8 are uniquely fixed. Next, a reflective umbrella 9
Is rotatable and is held at a central position facing the optical panel 7, as shown in FIGS. 4 and 5.

FIG. 4 is a side view showing a state when the apparatus is carried, in which the taking lens barrel 2 and the AF projecting / receiving windows 5, 5 ',
The viewfinder covers the front surface of each optical system of the window 6 to prevent adverse effects and stains due to external force.

FIG. 5 is a side view showing an actual use state of the camera. The lid member 3 is held and fixed in a state of being rotated about 180 degrees from the state of FIG. 4 about the hinge portions 4 and 4 '. At this time, in FIG. 5, a switch, which is switched according to the rotation of the lid member 3 (not shown), is arranged around the hinge portions 4 and 4 ', and it is detected that the switch rotates by a certain angle, and the photographing lens barrel automatically moves. And it is displaced to a state where it can be photographed (state shown in the figure).

Further, the hinge portions 4 and 4'include electric connection parts for performing flash light emission. Further, although not shown in the figure, in a portion that does not affect the optical characteristics of the lid member 3, a minimum number of electric mounting components necessary for performing flash light emission and the reflector 9 are rotated. The mechanical parts of are built in.

In the camera of the present embodiment, in the above-described use state, the flash light emitting portion is held at a position away from the photographing lens barrel as shown in FIG. There is.

Next, the irradiation angle changing operation will be described. The irradiation angle changing operation is performed by rotating the reflector 9 around the flashlight emitting tube 8. It should be noted that either the reflecting umbrella 9 may be configured to be automatically operated, or the reflecting umbrella 9 and the flashlight emitting tube 8 may be integrally rotated.

When the focal length is long (at the time of telephoto correspondence), the size of the subject is large and the red eyes are easily noticeable. Therefore, in this embodiment, when the focal length is long (in the telephoto state), the panel portion above the center of the light emitting portion is used to efficiently collect light.

FIG. 6 shows a ray trace in the condensed state (a state corresponding to the telephoto state).

In the state shown in FIG. 6, the reflector 9 is fixed upward by a predetermined angle, and most of the direct light from the flash tube 8 and the reflected light from the reflector 9 are in the optical panel 7.
The light enters the fine prism portion 7b provided on the upper part of the.

Here, the direction of the light is converted into a substantially constant direction by the total reflection, and the light is emitted from the optical panel 7 in a condensed state. At this time, depending on the shape of the reflective umbrella 9,
Although there is a component that does not directly enter the optical panel 7 after exiting from the above, by disposing the reflection plate 10 on the facing surface of the optical panel 3, it does not enter the optical panel 7 directly after exiting from the reflector 9. The component is converted into an angular component which is almost equivalent to a light ray reflected by the reflection surface 10, emitted from the reflector 9 to the optical panel 7 and then directly incident on the optical panel 7, and is incident on the upper portion of the optical panel 7. The light is emitted in a state where it is condensed into a substantially predetermined angle component.

According to this method, it is possible to realize an optical system with a good light-collecting efficiency without drastically increasing the size of the lid member 3. In addition, the light emission emitting part is located at the upper part (7
Since it is located at b) and therefore is away from the photographing optical axis of the camera, it has a great effect on the red-eye effect, and is particularly effective as a lighting device in a telephoto state in which the eyes of a subject are greatly expressed.

Further, the trace of the representative ray in the optical panel in this state will be described with reference to FIG. 7 which is a partially enlarged view of FIG.

As shown in the figure, the direct light from the flash tube is
First, the light is incident (refraction) from the prism surface on the arc tube side, is totally reflected by the incident surface on the opposite side, and is emitted (refraction) from the object side surface of the optical panel.

Next, the necessary conditions for setting each prism surface for taking the above optical path will be described. In FIG. 7, θ = angle between the direction of the main light flux from the light source and the horizontal direction α _n = inclination of the _nth prism entrance surface of the optical panel β _n = total reflection surface of the nth prism of the optical panel If the inclination n is the refractive index of the material of the optical panel, α _n , β _n
The following range is desirable.

0 ≦ α _n ≦ 90 ° (1-1) 0 ≦ β _n ≦ 90 ° (1-2)

Next, referring to FIG. 8 showing the optical path of the incident light incident on the prism, the optimum angle at which the light beam 30 aligned in one direction by the reflector 9 is incident on the Fresnel surface will be described.

As shown in the figure, three types of optical paths are conceivable even for rays incident from the same direction depending on the position of the light source and the Fresnel angle.

First, the light ray 30a enters from the prism entrance surface 7b ₁ of the prism portion 7b and directly reaches the exit surface 7c without passing through the total reflection surface 7b ₂ .

As shown in the figure, the light is not emitted from the emission surface 7c,
Although it is almost totally reflected, it may be refracted and emitted depending on the position of the light source.

The light ray 30b is incident from the incident surface 7b ₁ in the optical path intended by the present invention, and is totally reflected by the total reflection surface 7b.
It is a component that is totally reflected at ₂ and then refracted at the exit surface 7c to be emitted.

Finally, the light ray 30c is a component that enters from the total reflection surface 7b ₂ and exits from the exit surface 7c without passing through the surface 7b ₁ .

From the above situation, the light rays 30a and 30
It is necessary to set the incident direction of the light source and the shape of the Fresnel surface so that c is as small as possible. In reality, the directions of incident rays also have a certain amount of variation, so it is necessary to determine the inclination and pitch interval of the Fresnel surface in consideration of this point as well.

Regarding the ideal numerical condition, first, in order to prevent the light ray 30c from directly hitting the total reflection surface 7b ₂ , the direction of the light ray and the Fresnel surface may be set as follows.

The following conditions must be satisfied in order to use even the light beam originally entering from the incident surface 7b ₁ as an effective light beam.

This condition will be described with reference to FIG. 9 which shows the optical path of the incident light which similarly enters the prism.

FIG. 9 is an enlarged view of a ray trace in an ideal state, where a to d represent the angle components shown below.

First, as a first condition, a necessary condition for preventing the generation of a ray that does not hit the total reflection surface 7b ₂ like the ray 30a shown in FIG. 8 is that the ray after refracting at the incident surface 7b ₁ is It is necessary that the light beam after refraction intersects with the total reflection surface 7b ₂ , that is, that the light beam after refraction rises from the inclination of the total reflection surface 7b ₂ .

Therefore, in FIG. 9, b> a ... (3) is the minimum condition.

If this relationship is expressed by the constants given so far, then θ + sin ^-1 {sin (θ-α _n ) / n}> 90 ° -β _n (3) '.

If this condition is satisfied, light can be guided to the total reflection surface 7b ₂ without fail by appropriately selecting the pitch of the prisms.

Next, a condition for total reflection of the light hitting the total reflection surface 7b ₂ is required.

That is, in FIG. 9, ∠c ≧ critical angle (4) is required.

This relationship is represented by the constants given so far: 180 °-(α _n + β _n ) -sin ^-1 {sin (θ-α _n ) / n} ≧ sin ^-1 (1 / n) ... (4) 'Finally, it is necessary that the light that hits the exit surface 7c is not totally reflected.

| D | <critical angle (5) Similarly, when expressed in a form organized by given constants, | 180 ° + θ−2 (α _n + β _n ) −sin ⁻¹ {sin (θ− α _n ) / n} | <sin ⁻¹ (1 / n) ... (5) ′ The above are the necessary conditions for the respective constants so as not to cause the light amount loss.

To summarize the above conditions in a simpler manner, first, for each angle, according to the equations (1-1) and (1-2), 0 ≦ α _n , β _n , θ ≦ 90 ° (6) From the conditional expressions (4) and (5) of the surface, α _n + β _n −θ> 0 ... (7) Further, according to the conditional expressions (2) and (3), when θ ≧ α _n , θ + β _n > 90 °. 8-1) theta <a _n Nobaai,shitatasubeta ^{_{n -sin -1 {sin(θ-α n )/n}> 90 °}} ... (8-2) is a necessary condition.

Ideally, each condition should be satisfied at the same time,
Actually, some conditions may not be satisfied due to various restrictions such as the thickness of the Fresnel prism, the processing state or the molding state, and the size at which the Fresnel prism can be arranged. However, although most of the assumed light rays pass through the predetermined optical path of refraction reflection and refraction, the efficiency is lowered, but the purpose of changing the direction of flash light emission can be almost achieved.

On the other hand, when the focal length is short (wide-angle correspondence), the reflector 9 is held in a state of facing the front so as to emit light and the light is diffused in a relatively wide range as shown in FIG. .

FIG. 10 is a view showing a state in which the wide angle is supported.
The optical arrangement for obtaining the light distribution corresponding to the wide-angle state of the taking lens will be described with reference to FIG. As shown, in this state, the reflector is in a state of facing the front. In addition, the cross section of the portion 7d arranged in front of the optical panel 7 has no power and has a light distribution characteristic determined by the direct light from the flash tube 8 and the reflected light from the reflector 9. Is irradiated.

In this case, the projection lens is also a wide-angle system, and the person is small, that is, the eyes are small and the red eyes are not conspicuous with respect to a long-distance subject in which the red-eye phenomenon is likely to occur. Therefore, the emission of the light emitting portion is allowed even closer to the projection optical system than in the telephoto state shown in FIG. 6, and a predetermined light distribution can be obtained while preventing red-eye.

Further, for the intermediate focal length in the above-mentioned telephoto correspondence and wide-angle correspondence, the reflector is gradually tilted,
This is performed by appropriately adjusting the amount of the component that goes to the center of the angle of view.

Furthermore, by rotating the reflecting umbrella 9 downward when photographing in a relatively short subject distance or in a macro state where red-eye is not a problem, the irradiation direction is relatively downward by a fixed angle. Irradiate a subject at a short distance.

FIG. 11 shows a case in which such a subject distance is relatively close and a distance where red eyes do not occur, or a case where the camera is in the macro photography mode. The irradiation state of will be described.

In this case, since it is premised that the subject distance is short, it is almost unnecessary to consider the red-eye phenomenon, and even for a short-distance subject, the light distribution is uniform at the subject distance. desired.

In the present embodiment, in order to achieve this state, the central light flux of the flash light is tilted downward by a predetermined amount so that it coincides with the photographing light flux at the object distance.

That is, as in the case of the light ray trace shown in FIG. 6, the direction of the light ray is changed by utilizing the total reflection at the prism portion 7a of the optical panel 7, and the main light beam is directed downward by a predetermined angle. It is configured to eject.

Also in this case, as in the case of FIG. 6, a reflecting plate 10 'is arranged on the opposite surface side of the optical panel to reflect the light flux which is trying to spread by a component other than the main light flux, and the angle of the main light flux is almost the same. By matching the components, the light is more efficiently collected and irradiated.

In the setting state of the reflector 9 as shown in FIGS. 6 and 11, the luminous flux from the flash tube is controlled even though the structure related to the irradiation from the flash tube is thin in the irradiation direction. The distance to the optical panel can be increased and the controllability of light is improved. (The angle from the top of the optical panel that faces the flash emission part is narrowed, and the angle range for controlling light on each side of the prism is narrowed. In addition, it is possible to perform a rapid light emission direction conversion using the total reflection of the prism surface, which is efficient.

On the other hand, in the optical panel, a vertical Fresnel lens is cut on the object side as well, so that the light can be efficiently condensed in the longitudinal direction of the flash tube 8. Since this Fresnel lens in the vertical direction is formed over the entire surface of the optical panel 7, it is possible to efficiently focus light in correspondence with all of the above-mentioned states, the telephoto state, the wide-angle state, the intermediate state, and the macro state. It is possible.

The rotating operation of the reflector is performed in conjunction with the zoom operation of the taking lens barrel 2. As the interlocking method, the movement from the taking lens barrel may be directly interlocked, or a drive source such as a motor may be provided inside the lid member 3 and the power may be used for driving. .

As described above, according to the structure of the illumination device of the first embodiment of the present invention, the thin type is capable of various irradiation states corresponding to zoom and macro, and the position of the light emitting portion corresponding to the red-eye phenomenon. It is excellent in that the conversion of can be done by a very simple method of rotating the reflector. In addition, the direction is changed by using total reflection, which is more efficient than the conventional method.

The shape of the reflector 9 and the reflectors 10 and 1
The shape of 0'can be set to any optimum shape according to the required light distribution of the illumination and the irradiation direction. Also,
In the above-mentioned embodiment, the power in the vertical direction is not provided when the reflector is facing the front, but it may be configured to optimize the light distribution by adding power also in this direction.

(Second Embodiment) FIGS. 12 to 14 are vertical sectional views showing a state in which a flash light emitting portion of a flash light emitting apparatus according to a second embodiment of the present invention is cut vertically to a flash light emitting tube. . Since the overall configuration can be configured in the same manner as in the first embodiment, this embodiment will mainly describe a method of varying the irradiation angle around the light emitting portion.

Reference numeral 11 denotes a flash arc tube which emits flash light, 12 denotes a parabolic reflector, and the portion behind the flash arc tube 11 is considered in consideration of the influence of the glass tube of the flash arc tube 11. It has a shape that corrects. Reference numeral 13 is an optical panel that is arranged to face the light emitting portion composed of the flash light emitting tube 11 and the reflector 12, and a light diffusing surface is formed around the central portion, and the upper portion is a flat surface and the lower portion is different. It is composed of a characteristic light diffusion surface.

Reference numeral 14 denotes a plane mirror disposed between the optical panel 13 and the light emitting portion consisting of the flash arc tube 11 and the reflector, and the center of which is supported by a shaft formed in the front-back direction on the paper surface (not shown). It is rotatably held. Reference numeral 15 is a reflector provided on the upper side, and 16 is a reflector provided on the lower side.

In the above structure, the change state of the irradiation corresponding to each state will be described below.

FIG. 12 shows an arrangement for obtaining a light distribution corresponding to the case where the taking lens focal length is short (wide angle), and the light substantially collimated by the reflector 12 is formed near the center of the optical panel 13. Further, the diffused surface 13a having a high degree of diffusion (in the present embodiment, a continuous surface of a cylindrical surface having a strong curvature) is diffused, and a light distribution distribution corresponding to a wide angle of view can be obtained.

At this time, the plane mirror 14 is arranged substantially parallel to the optical axis of the flash light emitting portion, and is arranged at a position where it hardly affects the ray trace between the flash light emitting portion and the optical panel 13.

Next, the state corresponding to the case where the focal length of the taking lens is long (in the telephoto state) will be described with reference to FIG. In this state, the plane mirror 14 is rotated clockwise by 45 ° about a central axis (not shown).

In this case, the light collected in the substantially horizontal direction by the parabolic reflector 12 is tilted at 45 °.
The light is reflected by the reflection plates 14 and 15 of the plate, enters the flat portion 136 of the optical panel 13, and exits as it is. Therefore, the light collected by the reflector can be emitted from the optical panel as it is, and the light can be emitted from the upper portion as in the first embodiment, so that the focal length is long ( Telephoto)
It is possible to prevent a problematic red-eye phenomenon.

FIG. 14 shows an optical arrangement for obtaining an appropriate light distribution when the subject distance is short.

As shown in the figure, this optical arrangement is a state in which the reflection plate 14 is rotated counterclockwise by 45 ° with respect to the state of FIG. A light beam that is condensed by the parabolic reflector 12 and travels substantially parallel to the emission optical axis travels downwards by the reflector 14.
After being reflected by the reflecting plate 16, the lower part 13c of the optical panel 13
After being incident on, diffused, and emitted toward the subject.
Here, the reflector 16 is 45 ° like the reflector 15 on the upper side.
However, the plane is set such that the center of the optical axis (the one-dot chain line in the figure) is tilted downward by a predetermined amount according to the distance of the short-distance subject. Therefore, as shown in the figure, the entire light distribution is tilted downward, and an effective light distribution without light amount loss can be obtained for a subject at a short distance.

A diffusion portion is provided on the lower side 13c of the optical panel 13 so that a predetermined light distribution can be obtained. It should be noted that the irradiation in this direction is premised on that the subject is close to the subject. Therefore, the red-eye effect is unlikely to occur even if the photographing optical axis and the flash emission optical axis are close to each other. Even if the light is diffused, the light amount is unlikely to be insufficient, which is convenient as a unit of the entire optical system.

In the above embodiment, the reflector 14 is used as a member for changing the light direction, but the shape is not necessarily limited to this. , May have diffusivity. In addition, the reflectors 15 and 16 may have the same curved surface. Further, instead of the reflection plate 14, a total reflection prism (triangular prism) or the like may be used to convert the light direction.

(Third Embodiment) FIGS. 15 and 16 are vertical sectional views of a flash light emitting portion for explaining a third embodiment of the present invention.

The entire structure can be the same as that of the first embodiment. In this embodiment, the method of changing the irradiation angle around the light emitting portion will be described as in the second embodiment.

The flash arc tube 11 and the reflector 12 have substantially the same shapes as those in the second embodiment, and are therefore designated by the same symbols. Reference numeral 17 denotes an optical panel fixedly arranged on the front surface of the light emitting portion. A Fresnel surface is formed on the upper surface on the subject side and a lower surface is formed on the subject side by the Fresnel surface and the light emitting tube side is diffused. A diffusion surface for this is constructed. Reference numeral 18 denotes a Fresnel lens arranged on the front surface of the reflector 12, which is configured to be rotatable about a light emission optical axis by a driving unit (not shown).

In the above structure, first, the light emission state corresponding to the long focal length (telephoto state) will be described with reference to FIG. First, the light emitted from the flash arc tube 11 is reflected by the substantially parabolic reflector 12 and then converted into a light beam substantially parallel to the optical axis. Next, the light enters the Fresnel lens 18, and the optical panel 1
7 is guided to the upper portion 17a.

Here, the Fresnel lens 18 is a Fresnel surface formed on the arc tube side at an equal angle, and has a function of converting only the direction of the parallel light flux. Originally, if a wedge-shaped lens is used to perform this conversion, there is no light amount loss on the edge surface and the efficiency is high, but the distance between the optical panel 17 and the Fresnel lens 18 is short, and it is thick to reduce the overall thickness. Matching is not good because it ends up. Therefore, in the present embodiment, this conversion is performed using a Fresnel lens that is easy and inexpensive to mold, and that can realize a rapid change in the light direction in a thin space.

Next, the light beam that has exited the Fresnel 18 enters the optical panel 17, is redirected again, and is radiated to the subject in the condensed state. Here, the Fresnel surface formed on the subject side of the optical panel 17 is obtained by rotating the shape of the Fresnel lens 18 by exactly 180 °.
2 We are in favor of re-creating the state of the light flux after emission by changing the position. With this configuration, the photographing optical axis and the emission optical axis can be separated from each other in a situation where the focal length is long and the red eye of the subject is easily conspicuous as in the first and second embodiments, and this is effective against the red eye phenomenon. is there.

Next, FIG. 16 shows a light emission state corresponding to a short focal length (wide angle state).

The state of FIG. 16 is a state in which the Fresnel lens 18 is rotated by 180 ° about the light emission optical axis. With this arrangement, the light flux that has passed through the Fresnel lens 18 is guided to the lower portion 17b of the optical panel 17 as opposed to the state shown in FIG. The light flux reaching the optical panel 17 is diffused by a predetermined amount by a diffusing surface provided on the side of the light emitting portion and spread to a required irradiation angle, and then the direction of the light is changed to a subject by a Fresnel surface provided on the subject. It is ejected after being done.

Also in this case, as in the first and second embodiments, in this diffused state, the light emission center moves to the lower side, that is, the side closer to the photographing optical system, but the photographing lens is in the wide-angle state and the subject at a long distance. On the other hand, the size of the eyes is small, and the red-eye phenomenon is unlikely to be a problem.

As described above, according to the third embodiment, it is possible to realize the variable irradiation angle in consideration of red-eye reduction by only the simple operation of rotating the Fresnel lens 18.
It has many advantages such as small size and low cost.

(Fourth Embodiment) FIGS. 17 and 18 are vertical sectional views of a flash light emitting portion for explaining a fourth embodiment of the present invention.

The overall structure is almost the same as that of the first embodiment, and the shape of the reflector is given a characteristic.

The flash luminous tube 8 and the optical panel 7 are the same as those in the first embodiment, and 19 is a rear reflector 20, 20 'formed so as to cover the rear portion of the flash luminous tube.
Is a front reflector that extends forward from the front reflector and is rotatable around a rotation shaft (not shown) near the front end side of the rear reflector, and reference numeral 21 is a holding member that holds and fixes the light emitting unit.

In FIG. 17, first, FIG. 17 shows an optical arrangement for obtaining a light distribution corresponding to a light diffusion state, that is, a state where the focal length of the taking lens is short. Front reflector 20,
20 'is held with a narrow opening, and among the light rays emitted from the flash light emitting tube, a light beam directed obliquely forward is reflected by this reflector and becomes diffused light and is emitted from the optical panel 7.

On the other hand, FIG. 18 shows the front reflectors 20, 21 '.
Shows a state of being rotated around a rotation shaft (not shown). As shown in the figure, the light rays emitted obliquely forward of the flash arc tube are directly reflected on the prism surfaces provided on the upper and lower parts of the optical panel without being reflected by the front reflectors 20 and 20 '. Similar to the first embodiment, this component is irradiated while being condensed on the subject side by utilizing the total reflection of the prism surface.

Therefore, as the overall characteristic, it is possible to perform the illumination in which the light rays are concentrated in the range of the narrow angle of view toward the subject. That is, it is possible to realize illumination with a high illuminance near the center corresponding to a photographing lens having a long focal length.

In each of the above-mentioned embodiments, the case where the optical panel has a circular shape has been described, but the shape is not limited to this shape and may have any shape, for example, a rectangular shape.

Further, in the above embodiment, the switching of the optical path between the telephoto state and the wide-angle state is performed by moving the reflecting plate, but the present invention is not necessarily limited to this mode, and the reflecting plates 20 and 20 'are transmitted. It is also possible to use a liquid crystal whose degree can be changed to change the amount of transmission, or to use liquid crystals divided into several zones to appropriately change the transmission position to change the light distribution as a whole.

Further, as a modification, a light control glass used for a building material whose light transmission amount can be changed according to the angle of incident light is used, and the light path is switched by changing the set angle to irradiate the light. The angle may be variable.

Further, with the structure as shown in FIG. 18, a member capable of partially shielding light or a liquid crystal is arranged on the front side (flash tube) of the optical panel 7, and depending on the required light distribution characteristics. You may comprise so that this range may be changed. FIG.
Considering the case of 8, the diffused light source can be obtained when the periphery is masked, and the light source in a condensed state can be obtained when the center is masked.

As described above, according to the configurations of the above-described embodiments, since the irradiation angle can be changed without changing the positional relationship between the flash tube and the optical panel, the wide-angle and telephoto images can be obtained. The irradiation angle corresponding to the angle can be obtained without changing the size of the entire shape of the optical system.

Also in this form, since the overall shape can be formed while being thin, space efficiency is extremely good, and matching is good as an illumination device of a camera. In addition, since the light emitting position is changed according to the irradiation angle, the red-eye phenomenon is likely to occur, and the shooting optical axis and the illumination optical axis are most distant from each other in the telephoto state, the eye size is small, and the red eye is relatively inconspicuous. It is easy to adopt a configuration in which the photographing optical axis and the irradiation optical axis are slightly closer to each other in a state corresponding to, and the red-eye reduction can be performed in good balance as a whole camera.

Further, since the amount of movement of the optical member accompanying the change of the irradiation angle is small, there are many advantages such as a large irradiation angle can be easily changed.

The present invention is not limited to the configurations of these embodiments, but may have any configuration as long as the functions shown in the claims or the functions of the configurations of the embodiments can be achieved. It goes without saying that it is okay.

Further, the respective embodiments or their technical elements may be combined as required.

Also, the present invention relates to various types of cameras such as a single-lens reflex camera, a lens shutter camera, and a video camera.
Further, the present invention can be applied to optical devices and other devices other than cameras, and further to devices applied to the cameras, optical devices and other devices, or elements constituting these devices.

In each of the above-mentioned embodiments, the flash arc tube 8 or 11 is the light projecting means of claims 1 and 6 of the present invention, and the optical panel 7 or 13 or 17 is the light distributing means of claim 1. The reflector 9 or the reflector 14 or the Fresnel lens 18 serves as any one of the two parts 7b, 7c and 7d of the optical panel or the optical panel of the optical panel. Some 13a, 13b,
Any two of 13c, or the upper part 17a and the lower part 17b of the optical panel 17 are in charge of the first and second light distribution parts of the second aspect, respectively.

[0105]

As described above, according to the present invention, it is possible to provide an irradiation device having a high irradiation efficiency and a variable irradiation state without increasing the size of the structure.

[Brief description of the drawings]

FIG. 1 is a perspective view of an entire camera for explaining a configuration of a first exemplary embodiment of the present invention.

FIG. 2 is a front view of the camera shown in FIG.

FIG. 3 is a top view of the camera including a cross-sectional view through the center of the flash tube of the camera of FIG.

FIG. 4 is a side view (when carried) of the camera of FIG. 1 including a partial cross section of a flash light emitting unit.

5 is a side view (in use) of the camera of FIG. 1 including a partial cross section of a flash light emitting section.

6 is a vertical cross-sectional view of the flash light emitting unit of the camera of FIG. 1 in a condensed state.

FIG. 7 is a partially enlarged view of a vertical cross-sectional view of the flash light emitting section of the camera of FIG. 1 in a condensed state.

8 is a partially enlarged view of a vertical cross-sectional view of the flash light emitting section of the camera of FIG. 1 in a condensed state.

9 is a partially enlarged view of a vertical cross-sectional view of the flash light emitting section of the camera of FIG. 1 in a condensed state.

FIG. 10 is a partially enlarged view of a vertical cross-sectional view of the flash light emitting unit of the camera of FIG. 1 in a diffused state.

11 is a partially enlarged view of a vertical cross-sectional view of the flash light emitting unit of the camera of FIG. 1 when a short-distance subject is handled.

FIG. 12 is a partially enlarged view of a vertical cross-sectional view of a flash light emitting unit according to a second embodiment of the present invention in a diffused state.

FIG. 13 is a partially enlarged view of a vertical cross-sectional view of a flash light emitting unit according to a second embodiment of the present invention in a condensed state.

FIG. 14 is a partially enlarged view of a vertical cross-sectional view of the flash light emitting unit according to the second embodiment of the present invention when it corresponds to a short-distance subject.

FIG. 15 is a partially enlarged view of a vertical cross-sectional view of a flash light emitting unit according to a third embodiment of the present invention in a condensing state.

FIG. 16 is a partially enlarged view of a vertical cross-sectional view in a diffused state of the flash light emitting section according to the third embodiment of the present invention.

FIG. 17 is a partially enlarged view of a vertical cross-sectional view in a diffused state of the flash light emitting section according to the fourth embodiment of the present invention.

FIG. 18 is a partially enlarged view of a vertical cross-sectional view of a flash light emitting unit according to a fourth embodiment of the present invention in a condensing state.

[Explanation of symbols]

 1 Camera Main Body 2 Photographing Lens Barrel 3 Lid Member 7, 13, 17 Optical Panel 8, 11 Flashlight Emitting Tube 9, 12 Reflector Umbrella 10, 10 ', 15, 16 Reflector 14 Reflector 18 Fresnel Lens 19 Rear Reflector 20 , 20 'front reflector

Claims (10)

[Claims] 1. A light projecting means for projecting light, a light distributing means for distributing light from the light projecting means with a predetermined light distribution characteristic, and a light projecting means for projecting the light to the light distributing means. An irradiation device, comprising: a variable unit for changing the direction. 2. The irradiation device according to claim 1, wherein the variable means changes the light projecting direction by rotating the light projecting means. 3. The irradiation according to claim 1, wherein the variable means changes a light projecting direction so that an incident angle when the light from the light projecting means enters the light distributing means changes. apparatus. 4. The variable means changes the light projecting direction of the light projecting means so as not to change the position where the light from the light projecting means enters the light distributing means. Irradiation device. 5. The irradiation device according to claim 1, wherein the variable unit changes a light projecting direction of the light projecting unit according to a focal length. 6. A first light distribution section that distributes light with a first light distribution characteristic, and a light distribution section that is provided integrally with the first light distribution section and that has the first light distribution characteristic An irradiation device comprising: a second light distribution unit that distributes light with different second light distribution characteristics, and a selection unit that selects the first and second light distribution units. 7. The irradiation device according to claim 6, wherein the selection unit selects which of the first and second light distribution units the light from one light projection unit is to be projected. 8. The selecting means changes the light projecting direction of the light projecting means to determine to which of the first and second light distribution sections the light from the light projecting means is projected. The irradiation device according to claim 7, which is selected. 9. The irradiation device according to claim 8, wherein the selecting means changes the light projecting direction by rotating the light projecting means. 10. The irradiation device according to claim 1, wherein the selection unit selects the first and second light distribution units according to a focal length.