JPH05113593A - Storoboscopic device - Google Patents

Abstract

PURPOSE:To eliminate the failure of a reflector in a storoboscopic device and to provide the storoboscopic device provided with the reflector which does not require a large space while a guide number and a light distribution angle are maintained. CONSTITUTION:A cylindrical light emitting tube 1 which emits flash light, the relector 2 which reflects the flash light emitted by the tube 1, an aperture part 3 which is provided on the reflector 2 and which is set so that an object 4 is directly irradiated with the flash light, first curved reflection parts 2a, 2b which are provided on the reflector 2 and which reflect the flash light toward the object 4 side through a gap between the tube 1 and a second curved reflection part 2c which is provided on the reflector 2 and formed along one part of the circumferential surface of the tube 1 by a fixed radius and which directly reflects the flash light toward the tube 1 and guides the reflected light to the aperture part 3 and the first curved reflection parts 2a, 2b.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a strobe device, and more particularly to a reflector in a strobe device used for illumination light such as photography.

[0002]

2. Description of the Related Art As is well known, a strobe device used for photography or the like has an arc tube consisting of a small-diameter flash discharge tube filled with xenon gas and the like, and the arc tube is located at the center of the interior. It is composed of a reflector that reflects the flash light emission forward and an electric circuit that drives the arc tube to emit light. FIG. 9 shows a basic shape of a conventional reflector 102. The reflector 102 is formed in a parabolic or elliptical vertical cross-section, is parallel to the arc discharge direction of the arc tube 101, has an inner surface mirror-finished, and is positioned at the center of the backside. It is formed so that the flash light emission of the tube 101 is reflected toward a subject to obtain a desired light emission characteristic. The vertical and horizontal dimensions of the vertical cross-sectional shape of the reflector 102 are 2 / 3D, where D is the vertical dimension of the front opening.

[0003]

When such a conventional strobe device is built into a camera, it is arranged as far away from the taking lens as possible in order to prevent the red-eye phenomenon. As shown in, the camera body 1
It will be arranged at a position above the film cartridge 104 mounted in the camera 03. However, as described above, since the reflector 102 has an elliptical or parabolic cross-sectional shape that is vertically symmetrical with respect to the arc tube 101, its storage height is high, and the vertical dimension of the entire camera is large. It becomes a harmful effect to downsize the camera. Further, in the conventional reflector 102, since the reflector 102 is formed in an elliptical shape, a parabolic shape, or a shape close to vertical symmetry, as shown in FIG. The light ray a emitted from 101 toward the rear obliquely is reflected on the inner surface of the reflector 102, and the arc tube 1
It returns to the outer peripheral surface of 01 and is reflected again outward, so the light bounced by the arc tube does not go in the target direction,
There was also a drawback that the luminous efficiency was lowered.

An object of the present invention is to eliminate the drawbacks of the reflector in such a conventional strobe device, and to provide a strobe device having a reflector that does not take up space while maintaining the same guide number and light distribution angle as those of the conventional strobe device. To provide.

[0005]

The strobe device of the present invention is provided with a cylindrical arc tube for emitting flash light, a reflecting umbrella for reflecting the flash light emitted by the arc tube, and the reflecting umbrella. An opening for directly irradiating the subject with the flash of light, and a first curved reflector provided on the reflector for reflecting the flash of light to the subject through a gap with the arc tube. It is provided on the reflector and is formed along a part of the circumferential surface of the arc tube with a constant radius to reflect the flash light directly toward the arc tube and to reflect the reflected light to the opening and the It is characterized by comprising a second curved reflecting portion that leads to the first curved reflecting portion.

[0006]

In the reflector, the flash light emitted from the arc tube is directly emitted from the opening toward the subject, and is also reflected by the first curved reflecting portion to be emitted toward the subject, and the second curved surface is also emitted. The reflecting portion directly reflects the light toward the arc tube, guides the reflected light through the arc tube to the opening and the first curved reflecting portion, and irradiates the subject.

[0007]

The present invention will be described below with reference to the illustrated embodiments. First, the feature of the reflector in the strobe device of the present invention is that the reflecting surface for irradiating the subject with flash light emitted from the arc tube is a reflecting mirror surface (first curved surface reflection) formed only on one side of the arc tube. Part) and a reflecting mirror surface (second part) which is connected to this reflecting mirror surface and which surrounds the outer peripheral surface of the arc tube approximately halfway and which reflects flash light toward the arc tube so as to pass through the tube. Curved surface reflection part).

FIG. 1 is a vertical sectional view of a reflector 2 in a strobe device showing a first embodiment of the present invention. The reflector 2 is obliquely above and right above the outer peripheral surface of the arc tube 1 (in FIG. 1).
A second curved reflecting portion 2c formed along the longitudinal direction of the arc tube 1 so as to cover about half (about 180 degrees) of the arc tube 1 and having a reflecting surface in close contact with the outer peripheral surface of the arc tube 1. This escape is continuous with the rear end of the second curved reflecting portion 2c to the lower right (in FIG. 1), bends from the reflecting portion 2c at a substantially right angle, and extends in the radial direction of the arc tube 1. It is formed by the portion 2d and the first curved reflecting portions 2a, 2b which are bent forward at a substantially right angle to the tip of the escape portion 2d and are continuously provided.

In the first curved reflecting portions 2a and 2b, the reflecting portion 2b at the front of the first curved reflecting portions 2a and 2b is formed on a relatively large partially arcuate reflecting mirror surface, and the reflecting portion 2a at the rear portion is the reflecting portion 2b.
Is formed by a relatively small reflecting mirror surface having a substantially arcuate half shape. The escape portion 2d is a portion for allowing the curved surface of the reflecting portion 2a to escape downward so that light near the points 2a-n reflected by the curved surface of the reflecting portion 2a does not hit the arc tube 1.

As described above, the reflector 2 is formed to have the first curved reflecting portions 2a and 2b and the second curved reflecting portion 2c, and the flash light emitted from the arc tube 1 is projected at four projection angles. The range is divided into θA to θD, and the subject 4 is irradiated with the light. Next, the operation will be described. First, the projection angle range θA from the opening 3 on the front surface of the arc tube 1 will be described.
Light is emitted directly toward the subject 4. Also, the first
The flash light of the projection angle range θB emitted toward the curved surface reflection portion 2b is reflected between the points 2b-1 to 2b-n of the curved surface and is irradiated toward the subject 4 within the range of the irradiation angle θB0. The curved surface of the reflecting portion 2b has points 2b-1 to 2-2.
It is a curved surface that gradually changes the angle at which the light hitting b-n is reflected to illuminate the subject. In addition, the first curved reflecting portion 2
The flash light of the projection angle range θC emitted toward a is reflected between the points 2a-1 to 2a-n on the curved surface, and the irradiation angle θ
The subject 4 is illuminated in the range of C0. The role of this curved surface is the same as that of the curved surface of the reflecting portion 2b. Then, the projection angle range θD emitted toward the second curved reflecting portion 2c
Of the flash light hits each point 2c-1 to 2c-n of the semicircular curved surface along the radius of the arc tube 1, is reflected, passes through the center of the arc tube 1 again, and falls within the range of the irradiation angle θD0. It is irradiated toward the outside. This reflected light is emitted from the front opening 3 in the projection angle range θA directly toward the subject 4, and the range of the irradiation angle θB0 on each curved surface of the first curved reflecting portions 2a and 2b. The light illuminates the subject 4 within the irradiation angle θC0. Therefore, all the flash light emitted from the arc tube 1 is efficiently emitted toward the subject 4 by the reflector 2.

FIG. 5 shows the data of the strobe device having the above-mentioned reflector 2, in which the vertical axis is the guide number (GNo) and the horizontal axis is the light distribution angle, which can be seen from this data. A light distribution that is satisfactory for shooting can be obtained.

FIG. 2 shows a state in which the strobe device 5 having the reflector 2 is incorporated in the camera body 6. In many cameras of this type having a photographing lens 7 in the center of the front surface, a curved surface portion 6a is formed from the upper portion of the front surface to the upper surface. Therefore, the strobe device 5 having the reflector 2 can be suitably arranged for such a camera. That is, as shown in FIG. 2, the reflector 2 is placed with the light emitting window toward the front of the camera in the corner formed by the right side of the front upper part of the camera body 6 and the right side of the upper front part and the right side. The strobe device 5 having it can be incorporated. With such a built-in structure, since the reflector 2 has a shape on only one side, the mounting space is small, it can be easily incorporated into a camera having the curved surface portion 6a, and it is far from the taking lens 7 accordingly. Since they can be arranged apart from each other, it is also effective in preventing the red-eye phenomenon.

FIGS. 3 and 4 show a state in which the strobe device 5 having the reflector 2 is made a retractable type and stored in the camera. However, in this case, the reflector 2 is arranged on the upper side.
At the time of shooting, the strobe device 5 is tilted upward as shown in FIG. 4 from the stored state shown in FIG. If it is built in in this way, it can be sufficiently stored in a vertically narrow space existing in the upper part of the mounting room of the film cartridge 8 in the camera body 6A or the spool room for film winding. .. If the retractable type is used in this way, the storage space can be made thin, and when the retractable type or the pop-up type is used, the movement amount can be small.

FIG. 6 is a vertical sectional view of a reflector 2A in a strobe device showing a second embodiment of the present invention. This reflector 2A has the same structure as the reflector 1 of the above-mentioned reflector 2 shown in FIG. 1 with the first curved reflecting portions 2a and 2b having two reflecting curved surfaces.
2 is formed. In order to form in this way, one curved surface reflection part 2a of FIG. 1 is abolished and the other curved surface reflection part 2b is extended to form one curved surface of the first curved reflection part 13 as shown in FIG. It is necessary to configure the reflector 2B having the above-mentioned structure so as to satisfy the irradiation angle to the subject.

However, as shown in FIG.
When a is eliminated and the curved surface of the curved reflecting portion 2b is extended to form one curved surface 13, the range of the semi-circular curved surface of the second curved reflecting portion 2c is 180 ° with respect to the center of the arc tube 1. + ΘF
It becomes an angle range of °. Therefore, a loss occurs at a projection angle in the range of θF °. In order to avoid this loss, each point 12b-1 to 12b-n of the reflection curved surface 12 must be kept away from the arc tube 1 as shown in FIG. Therefore, the reflector 2A becomes large, but it is possible if this type is effective in terms of design. The irradiation angle range in this case is θe. In addition,
Even in the case of the reflector 2B shown in FIG. 7, it is possible if the light in the angle range of θF ° is ignored.

FIG. 8 is a vertical sectional view of a reflector 2C in a strobe device showing a third embodiment of the present invention. This reflector 2C has a partially arcuate reflection curved surface 10a, 10b, 10c.
Are formed by increasing. Light distribution angle θ in this case
Although g, θh, and θi are narrow, it is effective in a camera having a long focal length because the light distribution angle may be narrow. Further, the first curved reflecting portions 2a and 2b in FIG. 1 can be formed by connecting a plurality of minute planes in series.

According to the present invention, the vertical and horizontal sizes are 4/5 D and D as shown in FIG. 10, and the size of the conventional reflector 102 shown in FIG. Although it is about the same, the size in the diagonal direction becomes extremely small, so when incorporating it into the camera, it is possible to effectively use the space that could not be used previously, which allows for changes in design. Becomes Furthermore, if the strobe device is arranged in an oblique direction, there is a remaining space in that direction, so other members can be arranged in this space, which contributes to downsizing of the camera.

Further, as shown in FIG. 12, the light a which is reflected by the reflector 102 and further reflected by the outer peripheral surface of the arc tube 101 to be a loss is, as shown in FIG. Since the second curved reflecting portion 2c is formed in a semicircular curved surface along the outer peripheral surface of the arc tube 1, the light a1 emitted from the center of the arc tube 1 is reflected by the second curved reflecting portion 2c. After that, it returns to the inside of the arc tube 1 again, and is further injected through the same tube to the other side. For this reason, this reflected light is emitted in the same direction as the light directly emitted from the arc tube, so that it is possible to design with good luminous efficiency.

[0019]

As described above, according to the present invention, when the light distribution characteristics, the luminous efficiency, and the like are the same as those of the conventional strobe device, the space required for the strobe device is almost half. The camera with the built-in can be miniaturized.

[Brief description of drawings]

FIG. 1 is an enlarged sectional view of a reflector in a strobe device showing a first embodiment of the present invention.

FIG. 2 is a perspective view of a camera incorporating the strobe device of FIG.

FIG. 3 is a schematic diagram showing a state in which the strobe device of FIG. 1 is made a retractable type and incorporated in a camera.

FIG. 4 is a schematic diagram showing how the strobe device shown in FIG. 3 is used.

FIG. 5 is a diagram showing a light distribution characteristic of the strobe device of the first embodiment.

FIG. 6 is an enlarged sectional view of a reflector in a strobe device showing a second embodiment of the present invention.

7 is an enlarged cross-sectional view showing a modified example of the reflector shown in FIG.

FIG. 8 is an enlarged sectional view of a reflector in a strobe device showing a third embodiment of the present invention.

FIG. 9 is an enlarged cross-sectional view showing an example of dimensions of a reflector of a conventional strobe device.

FIG. 10 is an enlarged cross-sectional view showing an example of dimensions of the reflector of the flash device according to the present invention.

FIG. 11 is a schematic diagram of a camera incorporating a conventional strobe device.

FIG. 12 is a diagram showing a state of a part of reflected light from a reflector in a conventional strobe device.

FIG. 13 is a diagram showing a state of a part of the reflected light of a reflector in the strobe device of the present invention.

[Explanation of symbols]

 1 ……………… Arc tube 2 ………… Reflector 2a, 2b …… First curved reflector 2c ………… Second curved reflector 3 ………… Opening 4 …… ………subject

Claims (1)

[Claims] 1. A cylindrical arc tube that emits flash light, a reflector that reflects the flash light emitted by the arc tube, and a reflector that is provided on the reflector for directly irradiating the subject with the flash light. An opening, a first curved reflecting portion provided on the reflecting umbrella to reflect the flash light toward the subject side through a gap between the reflecting tube and the arc tube, and the reflecting tube provided on the reflecting umbrella. Is formed so as to follow a part of the circumferential surface of the lamp with a constant radius, reflects the flash light directly toward the arc tube, and guides the reflected light to the opening and the first curved reflecting portion. A strobe device comprising: a curved reflecting portion;