JP2000089095A - Window member for af range-finding for camera - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent one part of a light beam projected from a light projection part from being made incident on an image forming part when the front parts of the light projection part and the image forming part are covered with one window member. SOLUTION: An AF range-finding unit 24 and an auxiliary light projection part 26 are disposed at the part of a front cover 16 and one window member 30 is arranged so as to protect the unit 24 and the projection part 26, and a decorative panel 32 is attached to the window member 30. The rear surface 30A of the window member 30 is provided with a groove 3004 for housing the partition part 1620 of the cover 16. Besides, a groove 3012 is formed between the part 3032 of the front surface 30B of the window member 30 corresponding to the image forming part 28 and the part 3034 thereof corresponding to the projection part 26. The bottom surface 3012C of the groove 3012 is inclined so that the projection part 26 side thereof is separated from the bottom surface 3004C of the groove 3004 of the rear surface 30A and the image forming part 28 side thereof approaches the bottom surface 3004C. Then, the partition part 3224 of the panel 32 is inserted into the groove 3012.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a window member for AF distance measurement of a camera mounted as an AF distance measurement window for automatic focusing.

[0002]

2. Description of the Related Art There are a passive system and an active system as an autofocus mechanism for focusing a subject image on a film surface. In the passive method, for example, a subject image is formed on each of two line sensors of an imaging unit, and a distance to the subject is calculated based on the position of the subject image on these line sensors. In the passive system, an auxiliary light projecting part is generally provided, and when the surroundings are dark enough not to form the subject image, a light spot such as visible light is emitted from the light projecting part to form a light spot on the subject. Then, the image of the light spot is formed on two line sensors of the image forming part. For example, the light beam is irradiated so that the light spot on the subject forms a striped pattern. In the active method, a light spot such as infrared light is formed on the subject by irradiating the subject with a light beam such as infrared light from the light projecting part of the camera regardless of the surrounding brightness, and the image of this light spot is formed on the line sensor of the image forming part. And calculates the distance to the subject based on the position of the light spot image on the line sensor. In the passive method and the active method, the focus adjustment mechanism is moved according to the calculated distance to focus the subject image on the film surface.

[0003]

By the way, in both the passive system and the active system, the light projecting section and the image forming section are arranged side by side on the front of the camera, and one transparent section is provided in front of the light projecting section and the image forming section. There is provided one covered with a window member made of plastic or the like. In the configuration described above, the light beam emitted from the light projecting unit enters the inside of the window member from the rear surface of the window member, and is emitted toward the subject from the front surface of the window member. A part of the light beam is reflected at the interface on the front surface of the window member, is guided inside the window member, and is incident on the image forming portion, which may cause an error in the distance measuring operation. The present invention has been devised in view of the above circumstances, and an object of the present invention is to provide a light projection unit and an image forming unit in which the distance in front of the image forming unit is one.
When covered by the window member, a part of the light beam emitted from the light projecting part is guided inside the window member and prevented from entering the image forming part, and the distance measuring operation is performed. An object of the present invention is to provide an AF distance measuring window member of a camera which can be reliably performed.

[0004]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a distance measuring light projecting section for irradiating an object with a light beam to form a light spot on the object, and forming an image of the light spot. A camera having a window member made of a light-transmissive material disposed so that a distance-measuring image-forming section facing the front of the camera body, and covering the front of the light-projecting section and the image-forming section. On the front surface of the member, a window member portion facing the front of the light emitting portion, a groove is formed to extend along a boundary between the window member portion facing the front of the imaging unit, the groove has a groove surface, The groove surface is formed so as to be inclined such that the light projecting portion side is away from the rear surface of the window member at a position corresponding to the boundary and the image forming portion side is close. Further, the present invention provides a distance measuring light projecting unit that irradiates a light beam on a subject to form a light spot on the subject, and a distance measuring image forming unit that forms an image of the light spot on a front surface of the camera body. A camera provided with a window member made of a translucent material so as to cover the front of the light emitting unit and the image forming unit, facing the front of the light emitting unit on the front surface of the window member. A groove is formed to extend along a boundary between the window member portion and the window member portion facing the front of the imaging section, the groove has a groove surface, and the groove surface has a window at a position corresponding to the boundary. The image forming apparatus is characterized in that it is formed so as to be inclined such that the light projecting unit side is separated from the rear surface of the member and the image forming unit side is approached. Further, the present invention provides a distance measuring light projecting unit that irradiates a light beam on a subject to form a light spot on the subject, and a distance measuring image forming unit that forms an image of the light spot on a front surface of the camera body. In a camera provided with a window member made of a translucent material so as to cover the front of the light projecting unit and the image forming unit, a front surface and a rear surface of the window member are provided in front of the light projecting unit. A groove is formed to extend along a boundary between the window member portion facing the front side and the window member portion facing the front of the imaging unit, and the groove on the front surface and the groove on the rear surface each have a groove surface. The groove surface of the groove is formed so as to be inclined so that the light projecting portion side is separated from the groove surface of the rear groove and the image forming portion side is approached. Further, according to the present invention, a decorative plate is mounted on a front surface of the window member, and the decorative plate has an opening for a light emitting portion having a size corresponding to a light projecting portion and an image forming portion facing the front of the camera body. And an opening for an image forming portion is formed by being partitioned by a decorative plate side partition, and the decorative plate side partition is accommodated in a groove on the front surface of the window member. Further, according to the present invention, a light projecting unit window and an image forming unit window are formed on a front surface of the camera body, the light projecting unit is disposed in the light projecting unit window, and the image forming unit is provided with the image forming unit. It is arranged in a window, the light-emitting unit window and the imaging unit window are partitioned by a main body-side partition, and the main body-side partition is housed in a groove on the rear surface of the window member. I do. Further, the present invention provides a distance measuring light projecting unit that irradiates a light beam on a subject to form a light spot on the subject, and a distance measuring image forming unit that forms an image of the light spot on a front surface of the camera body. In a camera provided with a window member made of a translucent material so as to cover the front of the light projecting unit and the image forming unit, a part of the light beam emitted from the light projecting unit is used. A reflector is formed on the window member for returning the light beam guided into the window member to the light projecting section side. Also, the present invention
A groove is formed on one of a front surface and a rear surface of the window member, and the reflection portion is formed by a groove surface forming the groove and the other of the front surface and the rear surface of the window member. Further, the present invention is characterized in that the groove is formed along a boundary between a window member portion facing forward of the light projecting portion and a window member portion facing forward of the image forming portion. Also,
The present invention is characterized in that the groove surface and the other of the front surface and the rear surface of the window member are inclined such that a distance between the light projecting unit and the image forming unit approaches.

[0005]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a front view of a camera, FIG. 2 is an explanatory view when a window member is bonded, FIG. 3 is an enlarged front view of a window member part with a decorative plate partially cut away, FIG. FIG. 5 is an enlarged sectional view of a partition portion, and FIG. 6 is a front view of a decorative plate. The camera body 14 of the camera 12 has a front cover 16 and a rear cover. A lens barrel 17 is provided at the center of the front of the camera body 14, and a finder window 18 is provided at the center of the front of the camera body 14. A strobe light 19 is provided at a corner at an upper portion of the front surface of the camera 14, and a release button 20 and the like are provided at an upper surface of the camera body 14. The camera 12 includes a passive type autofocus mechanism 22, and performs a distance measurement operation for focusing the subject image on the film surface by half-pressing the release button 20.

[0006] As shown in FIGS. 2 to 4, the autofocus mechanism 22 is provided with a front cover 1 located above the lens barrel 17.
An AF distance measuring unit 24 and an auxiliary light projecting unit 26 are provided in six parts. The AF ranging unit 24 includes an image forming unit 28 having two line sensors for forming a subject image, and an auxiliary light projecting unit 26.
Are a light source 2602 and a lens 260 for irradiating an infrared beam.
4 and so on. When the surroundings are dark enough that an image of the subject is not formed, a light beam is emitted from the light projecting unit 26 to form a light spot on the subject, and the image of the light spot is formed on the two line sensors of the image forming unit 28. The distance to the subject is calculated based on the position of the subject image on the line sensor, and the focus adjustment mechanism is moved according to the calculated distance to focus the subject image on the film surface. .

As shown in FIGS. 2 to 4, one window member 30 (an AF distance measuring window member) is provided so as to protect the AF distance measuring unit 24 and the light projecting unit 26. 3
A decorative board 32 shown in FIG. Note that FIG.
As shown in FIG.
An LED for displaying a light metering unit 34 and a self-timer is provided between the finder window 18 and the strobe 19 in the portion.
36, a remote control operation receiving element 38 is provided, and the window member 3 is provided so as to protect the photometric unit 34 and the like.
A window member 40 having a translucency different from 0 is provided, and the decorative plate 32 is also attached to the window member 40.

As shown in FIG. 2, an imaging section window 1602 for allowing the imaging section 28 to face the front cover 16 located above the lens barrel 17 is formed.
Window 160 for allowing the light projecting unit 26 to face below the window
In the present embodiment, the opening forming the finder window 18 and the imaging section window 1602 are formed continuously. The image forming unit window 1602 is formed in a horizontally long rectangular shape on the left and right sides, and the light projecting unit window 1604 is formed in a circular shape with a cutout at the bottom, and the image forming unit window 1602 and the light projecting unit window 16 are formed.
Reference numeral 04 denotes a partition 16 integrally formed with the front cover 16.
It is divided by 20. Note that in FIG.
630 is a window formed in the front cover 16, and the photometric unit 34 is disposed in the window 1630.

The window member 30 is formed of a translucent transparent plastic plate or the like. As shown in FIGS. 2 and 4, the window member 30 corresponds to the front of the finder window 18, the image forming section 28, and the light projecting section 26. The part is thick and the other parts are thin. More specifically, a concave portion 3002 is provided around the rear surface 30A of the window member 30 facing the camera body 14 side. Further, a groove 3004 for accommodating the partition 1620 is provided. The groove 3004 is provided in a portion of the window member 30 corresponding to the image forming portion 28 and the light projecting portion 2.
6 are provided.

A window member 30 facing the front of the camera 12
A portion 3030 corresponding to the finder window 18 and a portion 303 corresponding to the front of the imaging unit 28
2. The portion 3034 corresponding to the front of the light emitting section 26 is thick,
A recess 3010 is formed around the periphery so as to make other portions thinner, and a groove 310 is provided between a portion 3032 corresponding to the front of the image forming portion 28 and a portion 3034 corresponding to the front of the light projecting portion 26.
012 are formed. And the groove 3012 is
As shown in FIG. 5, the window member portion 30 in front of the imaging unit 28
32 side surface 30 parallel to the optical axis near the light emitting unit window 1604
12A and a side surface 3012B parallel to the optical axis of the window member portion 3034 in front of the light projecting portion 26 near the imaging portion window 1602.
And a bottom surface 3012C (corresponding to a groove surface in the claims) connecting the inner portions of the side surfaces 3012A and 3012B. The bottom surface 3012C is a rear surface 30A.
The groove 3004 is formed as a flat surface that is inclined such that the light projecting unit 26 side is away from the bottom surface 3004C (corresponding to the groove surface in the claims) and the image forming unit 28 side is close. This inclination is shown by a thin line (a) in FIG. 2, and the bottom surface 3012C is formed by an inclined surface extending radially around the light projecting portion 26. The rear surface 30A of the window member 30 is
Around the front cover 1 with adhesive or double-sided tape
6, the opening edge of the front cover 16 is located in the recess 3002, and the front cover 1 is located in the recess 3004, as shown in FIG.
Six partitions 1620 are accommodated.

A decorative plate 32 is mounted on the front surface 30B of the window member 30 and the front surface of the window member 40. The decorative plate 32 is formed of a light-shielding plastic plate or the like, and the decorative plate 32 has a plurality of openings formed therethrough in the thickness direction. As shown in FIGS. 1 and 6, these openings are an opening 3202 for a finder window and an opening 32 for an imaging section.
04, light emitting unit opening 3206, light measuring opening 3208, L
An ED opening 3210 and a remote control window opening 3212 are separated by a decorative plate 32 between these openings. A partition of the decorative plate 32 is provided between the image forming unit opening 3204 and the light emitting unit opening 3206. It is partitioned by 3224. Then, the openings 3202, 3204, 3206,
The portion of the decorative plate 32 between 3208, 3210, and 3212 is formed by the recess 3010 on the front surface 30 </ b> B
0, the decorative plate 32 is attached to the front cover 16 with an adhesive or a double-sided tape or the like. As shown in FIG. It is configured to be sandwiched between the decorative plate 32 portions. At this time, the partition 3224 between the image forming unit opening 3204 and the light projecting unit opening 3206 is
012, the front surface 30B of the window member 30 and the decorative plate 3
2 are formed so that the front surface is flush.

According to the present embodiment, a dotted line (a) in FIG.
As shown by, even if a part of the light beam emitted from the light projecting unit 26 enters from the back surface 30A of the window member 30 toward the image forming unit 28 inside the window member 30, the bottom surface 301
Since 2C is inclined as described above, the light beam is guided inside the window member 30 by reflection at the interface between the bottom surface 3012C of the groove 3012 and the interface between the bottom surface 3004C of the groove 3004, and the light is transmitted to the light projecting portion 26 side. Will come back to.
Therefore, it is possible to prevent the light beam emitted from the light projecting unit 26 from being guided inside the window member 30 and to be incident on the image forming unit 28, thereby making it possible to reliably perform the distance measuring operation. . Then, such an effect is simply obtained by the groove 301.
This can be achieved by a simple configuration in which the second bottom surface 3012C is inclined.

In this embodiment, the partition 3024 of the decorative plate 32 is provided in the groove 3012 of the front surface 30B of the window member 30.
Has been described, but the present invention is also applied to a case where the decorative board 32 does not have the partition portion 3224 or does not have the decorative board 32 itself. In this case, the groove 3012 Will not contain anything. Further, in the present embodiment, the case where the grooves 3012 and 3004 are formed on both the front surface 30B and the rear surface 30A of the window member 30 has been described. However, as shown in FIG. The present invention can be applied to the case where the groove 3012 is formed only in the window 30B or the case where the groove 3004 is formed only in the rear surface 30A of the window member 30 as shown in FIG. That is, in the present embodiment, the reflecting portion that returns the light beam guided to the inside of the window member 30 by a part of the light beam emitted from the light projecting portion 26 to the light projecting portion 26 side is a front surface of the window member 30. 30
B and the rear surface 30A have been described as having the grooves 3012 and 3004 on both sides.
It may be constituted by one of the grooves 3012 and 3004 of the front surface 30B and the rear surface 30A.

As shown in FIG. 7, a front surface 30 of the window member 30 is provided.
In the case where the groove 3012 is formed only in B, the front surface 30B
The bottom surface 3012C (corresponding to the groove surface in the claims) of the groove 3012 is such that the light projecting unit 26 side is away from the rear surface 30A of the window member 30 at a position corresponding to the bottom surface 3012C, and the image forming unit 28 side is close. It is formed to be inclined. Also, as shown in FIG.
When only the groove 3004 is formed, the bottom surface 3004C (corresponding to the groove surface in the claims) of the groove 3004 on the rear surface 30A is projected onto the front surface 30B of the window member 30 at a position corresponding to the bottom surface 3004C. It is formed so as to be inclined such that the light part 26 side is separated and the image forming part 28 side is approached. In FIG. 8, reference numeral 3250 denotes a printing unit for bordering a window frame formed on the front surface 30B of the window member 30 as a substitute for a decorative board.

Further, the groove 301 in the front surface 30B of the window member 30
2 and the shape of the groove 3004 in the rear surface 30A are not limited to the shapes having the bottom surfaces 3012C and 3004C as in the embodiment, and for example, the grooves 304 in the front surface 30B of the window member 30 in FIG.
As shown in FIG. 10 and a groove 3060 on the rear surface 30A of the window member 30 shown in FIG. 10, the cross section may have a triangular shape with two surfaces without a bottom surface. In the case shown in FIG. 9, the light projecting portion 26 of the groove surface forming the groove 3050 is formed.
Groove surface 3050C located closer to the rear surface 30 of window member 30
10, the reflecting portion is formed. In the case shown in FIG. 10, the reflecting portion is formed by a groove surface 3060C located closer to the light projecting portion 26 and a front surface 30B of the window member 30 among the groove surfaces forming the groove 3060. Will be done. In the embodiment, the passive type autofocus mechanism has been described. However, the present invention is similarly applied to an active type autofocus mechanism.

[0016]

As is apparent from the above description, according to the present invention, in the camera in which the front of the distance measuring light projecting unit and the distance measuring image forming unit is covered with one window member, Since the reflection member that returns the light beam guided to the window member to the light projection part side is provided on the window member, a part of the light beam emitted from the light projection part is guided inside the window member to form an image. It can be prevented from being incident on the section, and the distance measurement operation can be performed reliably.

[Brief description of the drawings]

FIG. 1 is a front view of a camera.

FIG. 2 is an explanatory view when bonding a window member.

FIG. 3 is an enlarged front view of a window member with a decorative plate partially cut away.

FIG. 4 is a sectional view taken along the line AA in FIG. 1;

FIG. 5 is an enlarged sectional view of a partition portion.

FIG. 6 is a front view of a decorative board.

FIG. 7 is an explanatory view of a case where a groove is formed only on the front surface of a window member.

FIG. 8 is an explanatory view of a case where a groove is formed only on the rear surface of the window member.

FIG. 9 is an explanatory diagram of a case where a groove is formed only on the front surface of a window member.

FIG. 10 is an explanatory diagram of a case where a groove is formed only on a rear surface of a window member.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 12 Camera 14 Camera main body 16 Front cover 24 AF ranging unit 26 Light emitting part 28 Image forming part 30 Window member 30A Rear surface of window member 30B Front surface of window member 32 Decorative plate 1620, 3224 Partition part 3004, 3012, 3050, 3060 Groove 3004C, 3012C, 3050C, 3060C Groove surface

Claims (9)

[Claims] 1. A distance-measuring light projecting section for irradiating an object with a light beam to form a light spot on the object, and a distance-measuring image forming section for forming an image of the light spot faces the front of the camera body. A camera provided with a window member made of a translucent material so as to cover the front of the light projecting unit and the image forming unit. A window facing the front of the light projecting unit on the front surface of the window member. A groove is formed extending along a boundary between the member portion and a window member portion facing the front of the imaging section, wherein the groove has a groove surface, and the groove surface has a window member at a location corresponding to the boundary. A window member for AF distance measurement of a camera, wherein the window member is formed so as to be inclined such that the light projecting portion side is away from the rear surface and the image forming portion side is approached. 2. A distance-measuring light projecting section for irradiating a subject with a light beam to form a light spot on the subject, and a distance-measuring image forming section for forming an image of the light spot faces the front of the camera body. A camera provided with a window member made of a translucent material so as to cover the front of the light projecting unit and the image forming unit. A window facing the front of the light projecting unit on a rear surface of the window member. A groove is formed extending along a boundary between the member portion and a window member portion facing the front of the imaging section, wherein the groove has a groove surface, and the groove surface has a window member at a location corresponding to the boundary. An AF distance measuring window member for a camera, characterized in that it is formed so as to be inclined such that the light projecting part side is away from the front surface of the camera and the image forming part side is approaching. 3. A distance-measuring light projecting section for irradiating an object with a light beam to form a light spot on the object, and a distance-measuring image forming section for forming an image of the light spot faces the front of the camera body. In a camera provided with a window member made of a translucent material so as to cover the front of the light emitting unit and the image forming unit, a front surface and a rear surface of the window member are provided in front of the light emitting unit. A groove is formed to extend along a boundary between the facing window member portion and the window member portion facing the front of the imaging unit. The front groove and the rear groove each have a groove surface, and the front groove. A window surface for AF distance measurement of a camera, characterized in that the groove surface is formed so as to be inclined such that the light projecting portion side is away from the groove surface of the rear surface groove and the image forming portion side is approached. . 4. A decorative plate is mounted on a front surface of the window member,
The decorative plate is formed such that a light emitting portion opening and an image forming portion opening corresponding to the light projecting portion and the image forming portion facing the front surface of the camera body are partitioned by a decorative plate side partition. ,
4. The window member for AF distance measurement of a camera according to claim 1, wherein the decorative plate side partition portion is accommodated in a groove on a front surface of the window member. 5. A light emitting unit window and an image forming unit window are formed on a front surface of a camera body, and the light emitting unit is disposed in the light emitting unit window, and the image forming unit is provided for the image forming unit. The light-emitting unit window and the imaging unit window are arranged in a window, and the main body-side partition is partitioned by a main body-side partition, and the main body-side partition is housed in a groove on a rear surface of the window member. An AF distance measuring window member for a camera according to claim 2, 3 or 4. 6. A distance-measuring light projecting portion for irradiating a subject with a light beam to form a light spot on the subject, and a distance-measuring image forming portion for forming an image of the light spot faces the front of the camera body. In a camera provided with a window member made of a translucent material so as to cover the front of the light projecting unit and the image forming unit, a part of the light beam emitted from the light projecting unit is used for the window. A window member for AF distance measurement of a camera, wherein a reflection portion for returning a light beam guided inside the member to the light projecting portion side is formed in the window member. 7. A groove is formed on one of a front surface and a rear surface of the window member, and the reflecting portion includes a groove surface forming the groove,
7. The AF distance measuring window member for a camera according to claim 6, wherein the window member is formed by the other of the front surface and the rear surface of the window member. 8. The image forming apparatus according to claim 7, wherein the groove is formed along a boundary between a window member portion facing forward of the light projecting portion and a window member portion facing forward of the image forming portion. An AF distance measuring window member of the camera described in the above. 9. The groove surface and the other of the front surface and the rear surface of the window member are inclined such that a distance between the groove surface and the image forming unit is closer to the light projecting unit side. 9. The AF distance measuring window member of the camera according to 7 or 8.