JPH09325399A - Finder illuminator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To miniaturize a camera and to reduce a cost in a finder illuminator illuminating a light transmission type display means for displaying photographing information inside a finder. SOLUTION: A Fresnel lens 22 is stuck to the exiting end face 20b of a prism 20 for illumination, and an LED 21 for illumination is disposed on an incident end face 20a side. The light source part of the LED 21 for illumination is disposed on the focusing position of the lens 22. Light emitted from the LED 21 is reflected by the reflection surface 20c of the prism 20, and becomes parallel light by the lens 22. The parallel light emitted from the lens 22 passes through a hole 7A for a photographing information display area inside a visual field frame 7, and irradiates the periphery of a segment for displaying the photographing information provided on an LCD 9 for display. Thus, the photographing information displayed on the segment for displaying the photographing information is made incident on the eye of a photographer through a pentagonal prism 11 and an eyepiece.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an illumination device for a finder of a camera, which displays photographing information by a liquid crystal element or the like in the finder.

[0002]

2. Description of the Related Art Heretofore, various cameras have been proposed in which various kinds of photographing information are displayed in a finder by a liquid crystal element or the like. For example, a finder illumination device has been proposed in which light emitted from a light emitting element such as an LED is emitted from a back surface of a liquid crystal element as a backlight in order to improve visibility of displayed shooting information. Further, in such a finder illumination device, in order to reduce the space between the light emitting element and the liquid crystal element, an apparatus has been proposed in which a prism is used to refract light to irradiate the liquid crystal element.

[0003]

On the other hand, the photographing information displayed in the viewfinder includes distance measurement information, strobe light information, AF information.
Since there are various target marks and the like, the ratio of the area for displaying the photographing information in the finder is relatively large. Therefore, in order to display such shooting information with good visibility, it is necessary to use a large light emitting element or a plurality of light emitting elements. However, if a large-sized light emitting element or a plurality of light emitting elements are used, a space for these elements becomes necessary, which makes it difficult to miniaturize the camera and increases the cost of the camera.

It is an object of the present invention to provide a viewfinder illumination device which can be downsized and the cost can be reduced.

[0005]

FIG. 1 shows an embodiment of the present invention.
4 will be described with reference to FIG. 4, the invention of claim 1 is a light-transmitting display means 9 for displaying photographing information in a viewfinder,
The optical member 20 is applied to a viewfinder illumination device of a camera including an illumination unit 21 that illuminates the light transmissive display unit 9 and an optical member 20 that guides the light emitted from the illumination unit 21 to the light transmissive display unit 9. The positive lens 2 on the exit end face 20b of the
The above object is achieved by disposing the two.

According to a second aspect of the present invention, the optical member is the prism 2.
0, and a positive lens 22 is formed integrally with the prism. In the invention of claim 3, the positive lens is the Fresnel lens 22. In the invention of claim 4, the illumination means 21 is arranged at the focal position of the positive lens 22.

According to the present invention, the light emitted from the illuminating means 21 is radiated to the light transmission type display means 9 through the optical member 20 by the positive lens 22 so that the light path is made substantially parallel light, and the light is transmitted. The information of the transmissive display means 9 is observed in the finder.

[0008] In the section of the means for solving the above-mentioned problems, which explains the configuration of the present invention, the drawings of the embodiments of the present invention are used to make the present invention easier to understand. However, the present invention is not limited to this.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an optical path diagram of a real image type finder to which the finder illumination device according to the present invention is applied, and FIG.
Is a longitudinal sectional view of a display unit for displaying photographing information, FIG. 3 is a prism development view of a finder illumination device according to the present invention, FIG. 4 is a perspective view showing a configuration of the finder illumination device according to the present invention, and FIGS. It is a figure which shows an image with photography information. As shown in FIG. 1, the real image type finder to which the finder illumination device of the present invention is applied is an objective lens 1, lenses 2, 3, and 4, a roof prism 5, a lens 6, a field frame 7, and polarizing plates 8A and 8B. A display unit 10 including a display liquid crystal element (display LCD) 9, and a pentaprism 11
And an eyepiece lens 12. The subject image incident from the objective lens 1 passes through the lenses 2, 3, and 4, the optical axis X is bent by the roof prism 5, passes through the lens 6, and is formed on the image forming surface 10A of the display unit 10. The optical axis X is bent by the prism 11 and the eyepiece 1
It is enlarged by 2 and enters the photographer's eyes. As shown in FIG. 2, the display LCD 9 is thermocompression bonded to the flexible printed board 32.
Characters and figures are displayed according to various shooting information input to.

As shown in FIG. 2, the lens 6 and the display unit 10 are provided.
An illumination prism 20 is disposed in the lower part in the middle of the. The illumination prism 20 is attached to a finder block 30, an illumination LED 21 is arranged below the entrance end face 20a thereof, and a Fresnel lens 22 is adhered to the exit end face 20b thereof. The lighting LED 21 is mounted on the flexible printed circuit board 31, and the electric power required for the light emission is supplied from the flexible printed circuit board 31.
Further, as shown in the development view of the illumination prism 20 of FIG. 3, the illumination LED 21 is positioned so that the light source portion 21A of the illumination LED 21 is arranged at the focal position of the Fresnel lens 22. The Fresnel lens 22 has no power in the direction perpendicular to the paper surface of FIG.

As shown in FIGS. 2, 3 and 4, the light emitted from the illumination LED 21 is emitted from the illumination prism 20.
The light is reflected by the reflecting surface 20c, is emitted from the emitting end surface 20b, and is collimated by the Fresnel lens 22.
The parallel light emitted from the Fresnel lens 22 is made into a uniform light beam by the diffusion seal 23, passes through the photographing information display area hole 7A in the field frame 7, and surrounds the photographing information display segment 9A provided on the display LCD 9. To expose. As a result, the photographing information displayed on the photographing information display segment 9A is observed by the photographer via the pentaprism 11 and the eyepiece lens 12.

FIGS. 5 and 6 are views showing a finder image incident on the photographer's eyes. FIG. 5 shows a state in which all the shooting information of the shooting information display segment 9A of the display LCD 9 is displayed. As shown in FIG. 5, the finder image includes a subject image area 25 and a photographing information display area 26, and a wide target mark 25A and a telescopic target mark 25B are displayed in the subject image area 25. In the shooting information display area 26, a flash shooting mark 26A and focusing distance display marks 26B to 26E are displayed. FIG.
Is, for example, a wide target mark 25A indicating that the taking lens is in a wide state, a focus distance display mark 26B indicating that the focus distance is infinite,
The flash photography mark 26A indicating that the flash photography is required is lit up. The optical system is configured so that the subject image incident from the objective lens 1 passes only through the subject image area hole 7B of the field frame 7, and in a state where light is not emitted from the illumination LED 21, It does not pass through the photographing information display hole 7A of the field frame 7. Therefore, in order to display the information in the photographing information display area 26, it is necessary to keep the illumination LED 21 constantly lit.

As described above, in this embodiment, the Fresnel lens 22 is adhered to the emission end face 20b of the illumination prism 20 in the finder, and the light source section 21A of the illumination LED 21 is arranged at the focal position of the Fresnel lens. Therefore, the light emitted from the illumination LED 21 is collimated and is applied to the shooting information display segment 9A of the display LCD 9. As a result, it is possible to irradiate the entire area of the photographing information display segment 9A with the small LED without using a large LED or a plurality of LEDs, and it is possible to significantly reduce the cost.
The space required for the lighting LED 21 can be reduced. Therefore, the degree of freedom in designing the camera is increased, and the size of the camera can be reduced.

Further, in the above-described embodiment, since the Fresnel lens 22 is adhered to the emission end face 20b of the illumination prism 20, the thickness of the optical member for making the light emitted from the illumination LED 21 parallel light is used. It can be reduced. Therefore, the distance between the field frame 7 and the illumination prism 20 can be reduced, which allows the camera to be further downsized.

In the above embodiment, the Fresnel lens 22 is used as a lens for converting the light emitted from the illumination LED 21 into parallel light, but the present invention is not limited to this, and as shown in FIG. Alternatively, a convex lens 28 may be used. However, since the Fresnel lens 22 has a smaller thickness than the convex lens 28, it is preferable to use the Fresnel lens 22 in order to downsize the camera. The convex lens 28 shown in FIG. 7 also has no power in the direction perpendicular to the paper surface of FIG.

Further, in the above embodiment, the Fresnel lens 22 or the convex lens 28 is adhered to the emission end face 20b of the illumination prism 20, and these are integrally formed. Prism 20
The Fresnel lens 22 and the convex lens 28 may be arranged with a space therebetween.

In the correspondence between the above-described embodiment and the claims, the display LED 9 serves as the light transmission type display means and the LE for illumination.
D21 constitutes an illuminating means, the illuminating prism 20 constitutes an optical member, and the Fresnel lens 22 and the convex lens 28 constitute a positive lens.

[0018]

As described above in detail, according to the present invention, the light emitted from the illuminating means is made into substantially parallel light by the positive lens and is radiated to the light transmitting type display means. The illumination means can also sufficiently irradiate the required area of the light transmission type display means. Therefore, it is not necessary to use a large-sized illuminating means or a plurality of illuminating means, whereby a large cost reduction can be achieved and a space required for the illuminating means can be reduced. Therefore, the degree of freedom in designing the camera is increased, and the size of the camera can be reduced.

According to the invention of claim 2, since the prism and the positive lens are integrally formed, the manufacture thereof is facilitated and the optical member for guiding the light of the illumination means to the light transmission type display means. Can be miniaturized, and thereby the camera can be further miniaturized. According to the invention of claim 3, since the positive lens is the Fresnel lens, the thickness of the lens can be reduced, and the camera can be further downsized. According to the invention of claim 4, the light emitted from the positive lens is made into parallel light, so that the light emitted from the illumination means can be efficiently applied to the light transmission type display means.

[Brief description of drawings]

FIG. 1 is an optical path diagram of a real image type finder to which a finder illumination device according to the present invention is applied.

FIG. 2 is a vertical cross-sectional view of a display unit that displays shooting information.

FIG. 3 is a prism development view of the finder illumination device according to the present invention.

FIG. 4 is a perspective view showing a configuration of a finder illumination device according to the present invention.

FIG. 5 is a diagram showing a viewfinder image together with shooting information.

FIG. 6 is a diagram showing a viewfinder image together with shooting information.

FIG. 7 is a diagram showing another embodiment of the present invention.

[Explanation of reference numerals] 1 objective lens 2, 3, 4, 6 lens 5 roof prism 7 field frame 8A, 8B polarizing plate 9 display LCD 10 display unit 11 pentaprism 12 eyepiece 20 illumination prism 21 illumination LED 22 Fresnel lens 28 Convex lens

Claims (4)

[Claims] 1. A light transmissive display means for displaying photographing information in a finder, an illuminating means for illuminating the light transmissive display means, and a light emitted from the illuminating means to the light transmissive display means. A finder illuminating device for a camera including an optical member, wherein a positive lens is provided on an emission end face of the optical member. 2. The finder illumination device according to claim 1, wherein the optical member is a prism, and the positive lens is formed integrally with the prism. 3. The finder illumination device according to claim 1, wherein the positive lens is a Fresnel lens. 4. The illuminating means is arranged at the focal position of the positive lens.
Finder lighting device described.