JPH02264231A - Display mark observation device - Google Patents

Abstract

PURPOSE:To select and display a display mark by constituting plural display marks to be displayed in a finder visual field by arranging microprisms concentrically and lighting the display marks with luminous flux from light sources which are arranged in specific directions. CONSTITUTION:The display marks 22 - 24 formed on a transparent flat plate 6 have at least two prism assemblies, i.e. a prism assembly consisting of concentric microprisms having a center of curvature at a 1st point O1 and a prism assembly consisting of concentric microprisms having a center of curvature at a 2nd point O2. Then the microprisms are arranged in an arcuate shape. The light sources 12a - 12c for lighting the display marks 22 - 24 are arranged on the prolongation of the line connecting the 1st point O1 as the center of the concentric circles and the nearly center point of the display marks. Then the light sources 12a - 12c light the respective display marks 22 - 24 independently. Consequently, only the display marks 22 - 24 can be lighted efficiently.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to a display mark observation device suitable for photographic cameras, video cameras, etc. This invention relates to a display mark observation device in which the display marks are spatially overlapped, so-called superimposed, so that the far-inder image and any display mark can be selected from a plurality of display marks and observed at the same time. .

(Prior Art) Conventionally, in viewfinder observation devices such as photo cameras and video cameras, various display marks related to photography such as shutter speed, aperture value, photometry range, distance measurement range, etc. are displayed along with the finder image formed by the objective lens. are displayed simultaneously, and both are observed through the eyepiece. The display mark is made of, for example, a liquid crystal, and is arranged at the center or periphery of the photographic screen, and is illuminated by an illumination means and observed through an eyepiece.

Of the display marks, the distance measurement mark indicating the distance measurement range for automatic focus detection and the metering mark indicating average metering, center-weighted metering, etc. are displayed spatially overlapping with the viewfinder image in the center of the shooting screen. There are many cases.

Recently, various automatic focus detection devices have been proposed that perform focus detection in a plurality of areas within a photographic screen.

In this case, it becomes necessary to provide distance measurement marks at multiple positions within the field of view of the finder. These plurality of distance measurement marks are displayed simultaneously, or only a target distance measurement mark is selected from among the plurality of distance measurement marks and independently illuminated and displayed.

However, finder systems such as cameras are generally small and housed in a narrow space, so multiple lighting means are arranged to display multiple display marks at the same time, or only the target distance measurement mark can be displayed independently. If an attempt was made to illuminate the entire distance measurement mark, the entire device would become larger and more complicated, and if an attempt was made to illuminate only one display mark, other distance measurement marks would be illuminated at the same time due to miniaturization.

These problems also apply to photometric marks.

(Problems to be Solved by the Invention) When providing a plurality of display marks within the field of view of a finder, the present invention comprises at least two prism aggregates each consisting of a plurality of minute prisms having a predetermined shape, and A display mark observation device suitable for a photographic camera, a video camera, etc., which can select a predetermined display mark from among the display marks, illuminate it with an illumination means, and observe the selected display mark well. For the purpose of providing.

(Means for solving the problem) A prism assembly A consisting of a plurality of concentric minute prisms having a center of curvature at a first point on a part of a transparent flat plate and a second prism assembly
A plurality of display marks made of at least two prism aggregates of prism assembly B made of a plurality of concentric minute prisms having a center of curvature at a point are provided, and the second point of the plurality of display marks is The center of curvature is common to at least two of the prism aggregates B, and for each display mark, only the display mark is illuminated on an extension line connecting the first point and the approximate center of the display mark. an independent illumination means for illuminating at least two of the plurality of display marks at the second point; This is something I decided to observe.

(Embodiment) FIG. 1 is a schematic diagram of an optical system of an embodiment when the display mark observation device of the present invention is applied to a single-lens reflex camera.

In the figure, reference numeral 1 denotes a photographing lens which has an aperture 2 in its optical path. 3
is a rotating mirror with a semi-transparent surface 3a in part,
The imaging light beam L1 is divided into two, one light beam L2 is guided to the finder system, and the other light beam L3 is guided to the focus detection device 13. A sub-mirror 4 is fixed to the mirror 3 and guides the light beam L3 that has passed through the semi-transparent surface 3a of the mirror 3 to the focus detection device 13. Reference numeral 5 denotes a focusing plate, the entrance surface 5a of which is a Fresnel lens, and the exit surface 5b of which is a matte surface.

Reference numeral 6 designates a transparent flat plate, and as shown in FIG. 2, for example, display marks 22 to 24 having at least two prism aggregates each consisting of a plurality of minute prisms, which will be described later, are provided in a part of the photographing screen 21 to indicate a focus detection range. It is formed. 7 is a condenser lens, 8 is a pentaprism, 9 is an eyepiece lens, 10 is an eye point for observation, and 11 is a photosensitive surface.

Reference numeral 12 denotes a light source and a display mark 2 formed on the transparent flat plate 6.
2 to 24, for example, an illumination means 1 such as an LED
It consists of 2a to 12d. Of these, lighting means 12a
~12c is an independent illumination means that illuminates only the corresponding display marks 22, 23, 24, and 12d is an independent illumination means that illuminates all display marks 22.
This is a collective illumination means for illuminating 24 to 24. Reference numeral 15 denotes a light guide prism, and for example, as shown in FIG.
It has d.

In this embodiment, for example, the light beam L5 from the light source 12 passes through the light guide prism 15, enters the inside of the transparent substrate 6 from the end surface, and advances through the transparent substrate 6 while being totally reflected between the plate surfaces of the display marks 22 to 22. 24, and the display mark is illuminated. A part of the light beam 16 that illuminates the display mark is reflected by one side of the plurality of micro prisms of one prism assembly that constitutes the display mark, is emitted in the direction of the optical axis L4 of the finder system, and is emitted into the pentaprism. 8 and an eyepiece 9 at an eyepoint 10 .

In this embodiment, when the display light beam reflected and emitted from the minute prism constituting the display mark (23) passes through the eyepiece lens 9, the light beams La and Lb passing through the edge of the finder aperture 16 fall within the angle α. It is set so that it spreads uniformly.

Next, the shapes of the display marks (22 to 24) of this embodiment will be explained.

As shown in FIG. 2, the display marks 22 to 24 each have a prism assembly A consisting of a plurality of concentric minute prisms having a center of curvature at a first point 01, and a concentric ring shape having a center of curvature at a second point o2. The prism assembly B includes at least two prism assembly B consisting of a plurality of minute prisms. Each micro prism is arranged in an arc shape.

The minute prisms of the prism assembly A and the prism assembly B are arranged, for example, every other prism or in each divided small region.

Then, one display mark 22 is displayed on the left and right display portions 22a.
, 22b. Other display marks 23.24
The same is true.

FIG. 3 is a cross-sectional view of a part of the prism-shaped display mark of this embodiment, and FIG. 4 is a perspective view of display marks 22 to 24 made of the prism. As shown in the figure, the minute prism has an arcuate triangular shape.

In FIG. 3, 17 is a minute prism 31A, B is a part of the prism assembly A having its center of curvature at the first point 01 in FIG. 2, and the minute prism 31B has a curvature at the second point 02 in FIG. It is a part of a prism assembly B having a center. The angles formed between the reflecting surfaces of the micro prisms of the prism assemblies A and H and the substrate may be the same or different.

17 is a colorless and transparent acrylic material, and 18 is a fine triangular prism body. A reflective film is applied to the surface of the prism body in the region 21a where incident light is reflected for display purposes. This forms a display section as a prism reflecting section. Further, the other region 21b is left untreated.

The acrylic materials 17 and 18 are made of materials with substantially the same refractive index, and the adhesive 1 has substantially the same refractive index as the acrylic materials 17 and 18.
9 glues both sides together. As a result, only the area 21a coated with the reflective film for the display part has a reflective effect due to the prism, and the incident light L5 is reflected in a predetermined direction, so that the luminous flux L for display is generated.
4, the light is guided to the eyepiece (not shown) side.

Next, independent illumination that illuminates only one target display mark in this embodiment will be described.

As shown in FIG. 5, the display marks 51 to 53 are formed on a metal plate by simply arranging a plurality of minute prisms in parallel rather than in concentric circles, and the display marks 51 to 53 are formed by light sources 51a and 52, respectively.
Assume that the configuration is such that the light is illuminated by the lights 53a and 53a. For example, assume that the light source 52a is turned on to illuminate the display mark 52. Then, as shown in FIG. 6, the luminous flux L62 incident on the prism of the target display mark 52 is reflected by the display mark 52 and enters an eyepiece (not shown), so that the display mark 52 is observed.

At the same time, the front light beam from the light source 52a also enters the prisms of non-target display marks 51 and 53 that are close to the display mark 52. At this time, display mark 51.53
The incident light beams L61°L63 are reflected in the same direction as the light beam L62, and a portion thereof enters an observation eyepiece (not shown).

Therefore, the non-target display marks 51 and 53 are also displayed within the viewfinder field of view together with the target display mark 52. This makes the person look strange and undesirable.

On the other hand, in this embodiment, as shown in FIG. 2, the light sources 12a to 12c for illuminating the display marks 22 to 24 are connected to a line connecting the first point 01, which is the center of the concentric circle, and the approximate center of the display marks. It is placed on an extension line. and light sources 12a, 12
b and 12c, each of the display marks 22 to 24 is independently illuminated. As a result, only the target display mark is efficiently illuminated, and even if the illumination light enters another display mark, the reflected light from the display mark will not enter the eyepiece, thereby achieving the target display. Only the marks are observed.

FIG. 4 is an explanatory diagram of the state of reflection of the luminous flux from the minute prism forming the display mark at this time.

The figure shows the display mark 2 when the light source 12c is turned on in FIG.
3 is shown.

As shown in the figure, when the light source 12c is turned on, the prism assembly A of the target display mark 23 has prism bodies arranged concentrically, so that the luminous flux L42 reflected by the prism assembly A of the display mark 23 enters the eyepiece of the finder system. However, the light incident on the prism assembly B of the display mark 23 is reflected obliquely as a beam L42a, and the light beam L41 . Since L43 is largely reflected in the oblique direction on the surface of the arc-shaped prism, these light beams L42a and L4
1. L43 no longer enters the eyepiece. For this reason,
Only the target display mark 23 is observed through the eyepiece.

As described above, in this embodiment, by arranging the display mark and the light source for illuminating the display mark as described above, only the target display mark together with the finder image can be observed within the field of view of the finder.

Next, collective illumination for illuminating a plurality of display marks at the same time will be described.

For batch illumination, the illumination means 12d placed at the second point 02 in FIG. 2 is used.

Of the two prism assemblies A and B that constitute the display marks 22, 23, and 24 in this embodiment, prism assembly B
Each of the micro prisms has a center of curvature at the second point 02.

For this reason, in this embodiment, the luminous flux emitted from the light source placed near the second point 02 is incident on the side surface of the transparent flat plate 6, and while being totally reflected between the transparent flat plates 6, the display marks 22, 23, .
The light is guided to 24 prism aggregates B.

FIG. 7 shows the state in which the light beams 71° and 72 incident on a part of the prism assembly B of the display marks 23 and 24 are reflected by the reflective surface of the prism assembly B at this time. Each minute prism of prism assembly B is at the second point 0.
The prisms have centers of curvature at 2, are arranged at equal inclination angles θ3, and reflect incident light 71 and 72 incident on the prism assembly B toward the eyepiece in the same direction.

At this time, since each minute prism of the prism assembly A has a center of curvature at a point different from the second point 02, the light beam incident on the prism assembly A is different from the direction of reflection of the light beams 71 and 72. It is reflected in the opposite direction and does not enter the eyepiece.

In this way, in this embodiment, a plurality of display marks 22, 23, and 24 can be observed simultaneously using one illumination means 12d.

8th. 9th. FIG. 10 is a schematic diagram of an embodiment showing the arrangement of display marks within the viewfinder field of view 21 of the display mark observation device according to the present invention.

FIG. 8 shows a case consisting of five display marks 81a, 81b to 81e. In the figure, illumination means 82a, 82b to 82e arranged on an extension line connecting the center point of the display mark and the center of curvature of the concentric micro prisms of the prism assembly A constituting each display mark are used to illuminate the direction of the arrow. Independent lighting is provided for each. Further, the display marks 81a to 81e are collectively illuminated from the direction of the arrow by an illumination means 84 arranged near the center of curvature 83 shared by the concentric minute prisms of the prism assembly B constituting each display mark.

FIG. 9 shows a case consisting of nine display marks 91a to 91i, and the configuration of each display mark is basically the same as that in FIG. 8. That is, nine illumination means 92a to 92i
The illumination means 93 performs independent illumination from the direction of the arrow.
The lights are illuminated all at once from the direction of the arrow.

FIG. 10 shows a case where a photometric mark is used as a display mark. Indication marks 101a, 10 on the right side of the figure
lb and 101c respectively indicate the range of spot photometry, partial photometry, and average photometry.

Illumination means 102a, 102b, and 102c corresponding to display marks 101a, 101b, and 101c perform independent illumination from the direction of the arrow, and illumination means 103 performs collective illumination from the direction of the arrow.

In this embodiment, the prism aggregates A and B constituting the display mark may have different prism inclination angles and may be constructed from separate areas, as shown in FIG. 11, for example.

By making the prism inclination angles of the prism assemblies A and B different in this manner, only the incident light beam from a predetermined direction is reflected to the eyepiece side, thereby allowing observation of the target display mark.

In each of the above embodiments, when a plurality of display marks are illuminated at once, it is not necessary to illuminate all the display marks, and a plurality of specific display marks may be illuminated.

In this embodiment, the prism constituting the display mark is not limited to a triangular shape, but may have any shape as long as it can reflect incident light in a predetermined direction.

(Effects of the Invention) According to the present invention, a light source is provided in which a plurality of display marks to be displayed within the field of view of a finder are each constituted by a plurality of micro prisms arranged concentrically as described above, and the display marks are arranged in a predetermined direction. By illuminating with a luminous flux from , it is possible to achieve a display mark observation device with a simple configuration that can select and display a plurality of target display marks or one display mark.

[Brief explanation of drawings]

Figure 1 is a schematic diagram of the optical system when the present invention is applied to a single-lens reflex camera, Figure 2 is an explanatory diagram of a portion of Figure 1, and Figures 3 and 4 form the display marks in Figure 1. 5 and 6 are schematic diagrams of a conventional display mark and its main parts; FIG. 7 is an enlarged perspective view of a portion of the display mark in FIG. 2; and FIG. 9th. FIG. 10 is an explanatory view of one embodiment showing the arrangement of display marks according to the present invention, and FIG. 11 is an enlarged perspective view of another embodiment of a minute prism constituting the display mark of the present invention. In the figure, 1 is a photographic lens, 3 is a rotating mirror 5 is a focusing plate, 6 is a transparent flat plate, 7 is a condenser lens, 8 is a pentaprism, 9 is an eyepiece lens, 22, 23, 24 are display marks, 12 .12a. 12b, 12c, 12d are light sources; 15, 15a; 15b, 15c, and 15d are light guide members, and 11 is a photosensitive surface. Figure Patent Applicant Canon Co., Ltd. 2d Figure Figure Figure Figure Figure Figure Figure

Claims (1)

[Claims] (1) Prism assembly A consisting of a plurality of concentric minute prisms having the center of curvature at the first point on a part of a transparent flat plate
A plurality of display marks are provided, each of which is made up of at least two prism aggregates of prism assembly B, which is made up of a plurality of concentric minute prisms having centers of curvature at the second point and the second point. At least 2 of the display marks
It is the common center of curvature of the two prism aggregates B,
For each display mark, an independent illumination means for illuminating only the display mark is arranged on an extension line connecting the first point and the approximate center of the display mark, and an independent illumination means for illuminating only the display mark is arranged at the second point. A display mark observation device characterized in that a collective illumination means for illuminating at least two of the display marks is arranged, and the display marks illuminated by the illumination means are observed.