JPH05257194A - Reflecting mirror for stroboscopic device - Google Patents

Abstract

PURPOSE:To stably fix a light source to a reflecting mirror by providing the reflecting surface with a concentric arc part whose sectional shape is centered on the light emission point of the light source and a tangential connection part which connects with the arc part and contacts the concentric circle. CONSTITUTION:The light source is cylindrically constituted, and a recessed part 16 which is formed behind the optical axis of the reflecting mirror 12 is constituted as a 1st arcuate reflecting surface 13 positioned on the concentric circle having its center at the light emission point of the light source 11. A 2nd reflecting surface 12a is sectioned almost linearly and positioned on the tangent of the concentric circle having its center at the light emission point of the light source 11. This concentric circle touches the outer peripheral surface of the light source 11 and the 1st arcuately-sectioned reflecting surface 13 of the recessed part 16. Further, the front end part of the 2nd reflecting surface 12a abuts on the upper and lower end parts of a Fresnel lens 17, fitted to the front part of a holding member 14, at an angle A (e.g. 60 deg.) respectively.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a strobe device for reflecting a light beam emitted from a light source by a reflecting mirror and irradiating the reflected light together with direct light from the light source.

[0002]

2. Description of the Related Art Strobe devices generally include
A reflective surface (umbrella) is provided on the back surface of the light source, and a combined light beam of the direct light from the light source and the reflected light from the reflective surface is emitted toward the subject. Since an elliptical reflecting mirror has been conventionally used in the strobe device, for example, an image is once formed through a Fresnel lens (condensing lens) provided on the front surface of the reflecting mirror.
When the light source is the first focal point, an image of the light source (second focal point) is formed in front of the light source.

By the way, the above elliptical reflecting mirror used in the conventional strobe device is difficult to attach to the strobe body, its work is difficult, and its complicated shape results in high processing accuracy. It had problems such as difficulty. Further, according to the elliptical reflecting mirror, when the light source is housed in the rear portion of the inner surface thereof, the mountability is poor because the outer peripheral surface of the light source and the inner peripheral surface of the housing portion have different curvatures. Therefore, as shown in FIG. 3, at the rear of the inner surface of the reflecting mirror,
A configuration may be considered in which a concave portion 10 having the same curvature as the outer peripheral surface of the light source 11 is formed and the light source 11 is housed in the concave portion 10. According to such a configuration, the reflecting mirror 9 having different curvatures is provided.
On the reflecting surface of the connecting portion 9a between the concave portion 10 and the concave portion 10, a problem such as unpredictable reflected light is generated.

[0004]

An object of the present invention is to solve the above problems of the strobe device, to improve the workability, to easily obtain the working accuracy, and to improve the mountability of the light source to the strobe body. An object of the present invention is to provide a strobe device capable of eliminating problems such as unpredictable reflected light being emitted due to a recess near the light source.

[0005]

SUMMARY OF THE INVENTION The present invention, which achieves the above objects, therefore comprises:
In a strobe device having a light source and a reflecting mirror for reflecting a light beam emitted from the light source, the reflecting mirror has an arc portion whose cross-sectional shape is a concentric circle centered on a light emitting point of the light source, and the arc portion. It is characterized in that it has a continuous tangential continuous portion in contact with the concentric circle. Further, the circular arc portion having a concentric circle centered on the light emitting point of the light source can be configured to have substantially the same curvature as the outer circumference of the light source.

[0006]

The present invention will be described below with reference to the illustrated embodiments.
FIG. 1 shows a first embodiment of a strobe device according to the present invention. The figure shows a cross section along the illumination optical axis O that passes through the center of the light source (xenon tube) 11 housed in the strobe main body 14, and is connected to the first reflecting surface (arc portion) 13. The reflecting surfaces (continuous portion) 12a are configured as a pair of flat reflecting surfaces arranged above and below the light source 11 as a center.

The light source 11 has a cylindrical shape and is housed in a recess 16 formed behind the reflecting mirror 12 along the optical axis. The inner surface of the concave portion 16 has the same curvature as the outer peripheral surface of the light source 11, and has a shape along the cylindrical light source 11. In other words, the concave portion 16 is configured as an arc-shaped first reflecting surface 13 located concentrically around the light emitting point of the light source 11 behind the optical axis of the light source 11.

The second reflecting surface 12a has a substantially linear cross section, and is located on a tangent to a concentric circle centered on the light emitting point of the light source 11. In this embodiment, the concentric circles coincide with the outer peripheral surface of the light source 11 and the first reflecting surface 13 of the recess 16 having an arcuate cross section. The second reflecting surface 12a is formed in a completely straight line. The front end of the second reflecting surface 12a is in contact with the upper and lower ends of the Fresnel lens 17 attached to the front of the strobe body 14 at an angle A (for example, 60 °).

According to the strobe device having the above structure, the luminous flux emitted from the light source 11 advances as follows. That is, of the luminous flux emitted from the light emitting point of the light source 11,
The light flux reflected by the second reflecting surface 12a located on the upper side of FIG. 1 proceeds as indicated by p in the figure. Further, of the luminous flux emitted from the light emitting point of the light source 11, the second reflecting surface 1 located on the lower side
The light flux reflected by 2a proceeds as indicated by q in the figure.

Therefore, the present stroboscopic device having such a reflection characteristic has a virtual image of the light emitting point of the light source 11 at the point a and the point b which are optically conjugate with the light emitting point of the light source 11 and the second reflecting surface 12a. This is equivalent to the fact that the light beams are emitted from the light source 11 'and the light source 11 ", which emit light at the points a and b, respectively, and the light beams p and q are No image is formed after passing through the Fresnel lens 17, and direct irradiation in the same direction is possible, so that uniform light distribution that does not cause unevenness in the vicinity of the center can be achieved. The emitted light flux includes direct light emitted directly from the light source 11 to the front (in the left direction in FIG. 1) in addition to the light reflected by the upper and lower second reflecting surfaces 12a. Light of The opposite direction the light beam is irradiated (the right direction in FIG. 1) is reflected by the first reflecting surface 13, is emitted forward with the light beam irradiated to the front of the.

FIG. 2 shows a second embodiment. Although the reflecting mirror 12 of the embodiment has an elliptical shape, unlike the conventional reflecting mirror 9 shown in FIG. 4, a concave portion 16 (first reflecting surface 13) is formed at a joint portion between the arc tube 11 and the rear portion of the reflecting mirror 12. Further, a second reflecting surface 12a, which is common to the first embodiment and is aligned with the tangent line of the concentric circle of the light source 11, is formed in a portion extending from the first reflecting surface 13 to the elliptical reflecting surface 12b. According to the reflecting mirror 12 having such a shape, it is possible to reduce the unevenness at the time of irradiation, which has occurred in the conventional elliptical reflecting mirror, and improve the light distribution characteristics.

FIG. 3 shows a third embodiment. In the figure, the difference from the reflecting mirror 12 in FIG.
2c is formed, the diameter of the light source (xenon tube) 11 is reduced, and a supporting spacer 20 is interposed between the light source 11 and the recess 16 (first reflecting surface 13). That is the point. The joint portion 12c is the Fresnel lens 1
The second reflecting surface 12a is configured so as to vertically contact the rear wall of the No. 7, and the second reflecting surface 12a forms an angle B (for example,
It is connected at 57 °). The spacer 20 itself is made of a transparent material, but is not limited to this.
You may use what formed the reflective surface in the part which contacts the light source 11. The reflecting mirror 12 having such a shape can also have the light distribution characteristics similar to those of the reflecting mirror 12 in FIG.

As described in the first to third embodiments, the conventional reflecting mirror has an elliptical shape and has a bulge in the vertical direction or around the illumination optical axis O as a center. Since 12 has a shape that does not have a bulge, the shape is extremely simple, the processing accuracy can be easily obtained, and the attachment property to the strobe body 14 can be improved and the attachment space can be reduced. Further, since the curvature of the concave portion 16 (first reflecting surface 13) is the same as the curvature of the outer circumference of the light source 11, the light source 11 can be mounted in an extremely stable state. Since the concave portion 16 and the reflecting mirror 12 are smoothly connected to each other, it is possible to eliminate the problems of the conventional elliptic mirror 9 shown in FIG. 4 such as unpredictable reflected light. .. In addition, the reflector 12
Since the shape is determined by the linear second reflecting surface 12a and the opening angle thereof, inspection and verification can be easily performed. At the time of manufacture, the light source and Fresnel lens are attached and the light source is actually mounted. It is also possible to estimate the entire scene when light is emitted.

[0014]

As described above, the strobe device of the present invention is
Since the reflecting mirror has an arc portion whose cross-sectional shape is a concentric circle centered on the light emitting point of the light source, and a tangential continuous portion that is continuous from this arc portion and is in contact with the concentric circle, stabilizes the light source as the reflecting mirror. Can be installed. In addition, the reflector
Since it does not have a bulge like the conventional elliptical mirror, the shape can be simplified and the processing accuracy can be easily obtained, the mountability to the strobe body can be improved, and the mounting space can be reduced. Further, since the arcuate portion and the continuous portion of the reflecting mirror are smoothly connected, it is possible to reliably eliminate the unpredictable reflected light that has conventionally been generated in the vicinity of the concave portion behind the light source of the reflecting mirror.

[Brief description of drawings]

FIG. 1 is a sectional view taken along an illumination optical axis showing a first embodiment of a strobe device according to the present invention.

FIG. 2 is a cross-sectional view showing a second embodiment of the strobe device according to the present invention along the illumination optical axis.

FIG. 3 is a sectional view taken along the illumination optical axis, showing the third embodiment of the strobe device according to the present invention.

FIG. 4 is a cross-sectional view showing a concave shape of an elliptical reflecting mirror used in a conventional strobe device.

[Explanation of symbols]

 11 11'11 "Light source 12 Reflector 12a Second reflective surface (continuous part) 13 First reflective surface (arc part) 14 Strobe body 17 Fresnel lens O Illumination optical axis

[Procedure amendment]

[Submission date] April 5, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] Full text

[Correction method] Change

[Correction content]

[Document name] Statement

[Title of Invention] Strobe reflector

[Claims]

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stroboscopic mirror for reflecting a light beam emitted from a light source on its reflection surface.

[0002]

2. Description of the Related Art Strobe devices generally include
A reflective surface (umbrella) is provided on the back surface of the light source, and a combined light beam of the direct light from the light source and the reflected light from the reflective surface is emitted toward the subject. Since an elliptical reflecting mirror has been conventionally used in the strobe device, for example, an image is once formed through a Fresnel lens (condensing lens) provided on the front surface of the reflecting mirror.
When the light source is the first focal point, an image of the light source (second focal point) is formed in front of the light source.

By the way, since the reflecting mirror used in the conventional strobe device has an elliptical shape, it is difficult to attach it to a holding member for holding the reflecting mirror, such as a strobe body or a camera, and its work is difficult. In addition, there is a problem that it is difficult to obtain the processing accuracy due to the complicated shape.
Further, according to the elliptical reflecting mirror, when the light source is housed in the rear portion of the inner surface thereof, the mountability is poor because the outer peripheral surface of the light source and the inner peripheral surface of the housing portion have different curvatures.
Therefore, as shown in FIG. 4, it is conceivable that a concave portion 10 having the same curvature as that of the outer peripheral surface of the light source 11 is formed in the rear portion of the inner surface of the reflecting mirror, and the light source 11 is accommodated in the concave portion 10. According to this, problems such as reflected light that is difficult to predict occur on the reflecting surface of the connecting portion 9a between the reflecting mirror 9 and the recess 10 having different curvatures.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems with a stroboscopic reflecting mirror, to improve the mountability of a light source, and to provide a stroboscopic reflecting mirror which has a simple shape and can be easily processed. It is intended to be provided.
Further, the present invention improves the mountability to a holding member that holds a reflecting mirror, such as a strobe body or a camera, and can reduce the mounting space, and further cause a problem such as unpredictable reflected light due to a recess near the light source. It is an object of the present invention to provide a stroboscopic mirror that can be eliminated.

[0005]

SUMMARY OF THE INVENTION The present invention, which achieves the above objects, therefore comprises:
In a stroboscopic reflector for reflecting a light beam emitted from a light source on its reflecting surface, the reflecting surface has an arc portion whose cross-sectional shape is a concentric circle centered on the light emitting point of the light source,
It is characterized by having a tangential continuous portion which is continuous from the arc portion and is in contact with the concentric circle. Further, the circular arc portion having a concentric circle centered on the light emitting point of the light source can be configured to have substantially the same curvature as the outer circumference of the light source.

[0006]

The present invention will be described below with reference to the illustrated embodiments.
FIG. 1 shows a first embodiment of a reflecting mirror 12 for a strobe according to the present invention. This figure shows a light source (xenon tube) 1
2 shows a cross section passing through the center of 1 along the illumination optical axis O, and the second reflection surface (continuous portion) 12a connected to the first reflection surface (arc portion) 13 is centered on the light source 11. It is configured as a pair of flat plate-shaped reflecting surfaces arranged at the top and bottom of the figure. Reference numeral 14 in the figure denotes a holding member for holding the reflecting mirror 12, such as a strobe body or a camera.

The light source 11 has a cylindrical shape, and is housed in a recess 16 formed in the rear of the optical axis of the reflecting mirror 12 so as to be perpendicular to the paper surface of FIG. The inner surface of the concave portion 16 has the same curvature as the outer peripheral surface of the light source 11, and has a shape along the cylindrical light source 11. In other words, the recess 16 is located behind the light source 11 along the optical axis.
It is configured as an arc-shaped first reflecting surface 13 located on a concentric circle centered on the light emitting point 1.

The second reflecting surface 12a has a substantially linear cross section, and is located on a tangent to a concentric circle centered on the light emitting point of the light source 11. In this embodiment, the concentric circles coincide with the outer peripheral surface of the light source 11 and the first reflecting surface 13 of the recess 16 having an arcuate cross section. Further, the second reflecting surface 12a can be configured as a perfectly linear shape. Second reflective surface 1
The front end of 2a is in contact with the upper and lower ends of the Fresnel lens 17 attached to the front of the holding member 14 at an angle A (for example, 60 °).

According to the reflecting mirror 12 for the stroboscope having the above structure, since the second reflecting surface 12a is formed in a substantially linear shape, it is attached to a holding member for holding the reflecting mirror, such as a strobe body or a camera. Can be facilitated and accuracy can be improved. In addition, since light rays that are difficult to predict at the position where the light source 11 is attached to the reflecting mirror 12 do not occur, uneven light distribution and the like due to light rays that are difficult to predict are less likely to occur. This is because the luminous flux emitted from the light source 11 proceeds as follows. That is, among the luminous fluxes emitted from the light emitting points of the light source 11, the luminous flux reflected by the second reflecting surface 12a located on the upper side of FIG. 1 proceeds as indicated by p in the figure. Further, among the luminous fluxes emitted from the light emitting points of the light source 11, the luminous flux reflected by the second reflecting surface 12a located on the lower side proceeds as indicated by q in the figure.

Since the reflecting mirror 12 having such a reflection characteristic is smooth because the second reflecting surface 12a is connected to the second reflecting surface 12a as a tangent to the arc of the first reflecting surface 13, the second reflecting surface 12a is smooth. Since there is no region where the curvature changes abruptly like the connecting portion 9a, it is possible to irradiate uniform light that does not cause unpredictable light and is less likely to cause uneven light distribution. Further, the reflecting mirror 12 has a light emitting point of the light source 11 and the second reflecting surface 12a.
At points a and b that are optically conjugate with respect to
It is equivalent to having a virtual image of the light emitting point of the light source 11, and as a result, it is as if the light sources 11 ′ and 11 ″ emit light beams at these points a and b, respectively. Further, since the light beams p and q do not form an image after passing through the Fresnel lens 17, they can be directly irradiated in the same direction, so that a uniform light distribution that does not cause unevenness near the center can be achieved. . Fresnel lens 1
The upper and lower second reflecting surfaces 12
In addition to the light reflected by a, the direct light emitted from the light source 11 directly to the front (in the left direction in FIG. 1) is included, and further, in the direction opposite to these light beams (in the right direction in FIG. 1). The light flux radiated onto the first reflection surface 13 is reflected by the first reflection surface 13 and is radiated forward together with the above-mentioned light flux radiated forward.

FIG. 2 shows a second embodiment. Although the reflecting mirror 12 of the embodiment has an elliptical shape, unlike the conventional reflecting mirror 9 shown in FIG. 4, a concave portion 16 (first reflecting surface 13) is formed at a joint portion between the arc tube 11 and the rear portion of the reflecting mirror 12. Further, a second reflecting surface 12a, which is common to the first embodiment and is aligned with the tangent line of the concentric circle of the light source 11, is formed in a portion extending from the first reflecting surface 13 to the elliptical reflecting surface 12b. According to the reflecting mirror 12 having such a shape, it is possible to reduce the unevenness at the time of irradiation, which has occurred in the conventional elliptical reflecting mirror, and improve the light distribution characteristics. Moreover, in the conventional elliptical reflector,
Mounting to a device that requires a strobe, such as a camera,
Although it was difficult because there was no straight line portion, such a shape would make a straight line portion, which would facilitate mounting and improve accuracy. Further, similarly to the above, since there is no sudden change in curvature like the connecting portion 9a shown in FIG. 4,
The unpredictable rays are gone.

FIG. 3 shows a third embodiment. In the figure, the difference from the reflecting mirror 12 in FIG.
2c is formed, the diameter of the light source (xenon tube) 11 is reduced, and a supporting spacer 20 is interposed between the light source 11 and the recess 16 (first reflecting surface 13). That is the point. The joint portion 12c is the Fresnel lens 1
The second reflecting surface 12a is configured so as to vertically contact the rear wall of the No. 7, and the second reflecting surface 12a forms an angle B (for example,
It is connected at 57 °). The spacer 20 itself is made of a transparent material, but is not limited to this.
You may use what formed the reflective surface in the part which contacts the light source 11. The reflecting mirror 12 having such a shape can also have the light distribution characteristics similar to those of the reflecting mirror 12 of FIG.

Conventionally, since an elliptic cylindrical light source is attached, there is a portion where the curvature changes abruptly like the connecting portion 9a shown in FIG. 4, but in the first to third embodiments described above. As described above, according to the reflecting mirror 12 of the present invention, since the entire reflecting mirror has a smooth shape from the mounting portion of the light source 11, it is possible to eliminate problems such as reflected light that is difficult to predict. it can. Further, since the reflecting mirror 12 has a linear portion, it is easier to attach the reflecting mirror 12 to a member that holds the reflecting mirror, such as a strobe body or a camera, as compared with the conventional one, and it is easy to obtain accuracy. Become. In particular,
In the reflecting mirror having the substantially linear second reflecting surface 12a,
It is more compact than the conventional elliptical shape (shown by the chain double-dashed line in FIG. 5). Further, since the shape of the reflecting mirror 12 is determined by the linear second reflecting surface 12a and the opening angle thereof, inspection and verification can be easily performed.

[0014]

As described above, in the reflecting mirror for a strobe according to the present invention, the reflecting surface is continuous with an arc portion whose cross-sectional shape is a concentric circle centered on the light emitting point of the light source, and from this arc portion.
The light source can be stably attached to the reflecting mirror because it has a tangential continuous portion in contact with the concentric circle. In addition, since the reflector does not have the bulge like the conventional elliptical mirror, the shape can be simplified and processing accuracy can be easily achieved, and it can be attached to a holding member that holds the reflector such as a strobe body or a camera. Can be improved and the mounting space can be reduced. Further, since the arcuate portion and the continuous portion of the reflecting mirror are smoothly connected, it is possible to reliably eliminate the difficult-to-predict reflected light that has conventionally occurred in the vicinity of the concave portion behind the light source of the reflecting mirror.

[Brief description of drawings]

FIG. 1 is a sectional view taken along an illumination optical axis, showing a first embodiment of a stroboscopic mirror according to the present invention.

FIG. 2 is a cross-sectional view showing a second embodiment of a stroboscope reflecting mirror according to the present invention, along the illumination optical axis.

FIG. 3 is a sectional view taken along the illumination optical axis, showing a third embodiment of a stroboscopic mirror according to the present invention.

FIG. 4 is a sectional view showing a concave shape of a conventional elliptical reflecting mirror.

FIG. 5 is a cross-sectional view showing the shapes of a stroboscopic reflecting mirror according to the present invention and a conventional elliptical reflecting mirror in comparison.

[Explanation of Codes] 11 11′11 ″ Light Source 12 Reflecting Mirror 12a Second Reflecting Surface (Continuous Part) 13 First Reflecting Surface (Arc Part) 14 Holding Member 17 Fresnel Lens O Illumination Optical Axis

[Procedure Amendment 2]

[Document name to be corrected] Drawing

[Name of item to be corrected] Figure 5

[Correction method] Added

[Correction content]

[Figure 5]

Claims (2)

[Claims] 1. A strobe device having a light source and a reflecting mirror for reflecting a light beam emitted from the light source, wherein the reflecting mirror has an arc portion whose cross-sectional shape is a concentric circle centered on a light emitting point of the light source. A strobe device having a tangential continuous portion that is in contact with the concentric circle and that is continuous from the arc portion. 2. The strobe device according to claim 1, wherein the arc portion has substantially the same curvature as the outer circumference of the light source.