JP2001281739A - Camera - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a camera with which a user can easily confirm the state of the taken picture of a subject person imediately and easily takes the picture again imediately in the case where it has become that the taken picture is unsatisfactory. SOLUTION: This camera is provided with an optical path diving means diving luminous flux transmitted through a photographing optical system, a photographic recording medium 2 arranged on the 1st scheduled image-forming of the optical path divided by the optical path dividing means, and an optical writing type spatial optical modulation element 1 arranged on the 2nd scheduled image-forming surface of the optical path divided by the optical path dividing means and set to be observed by a finder optical system, and the picture taken and recorded on the medium 2 is confirmed by the element 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a camera capable of confirming a photographed image of a subject, such as a still camera, in a stationary state.

[0002]

2. Description of the Related Art A viewfinder of a conventional still camera is composed of an optical viewfinder. In particular, a viewfinder of a single-lens reflex camera jumps up a subject light transmitted through a photographing lens and guides it to a viewfinder optical system by a mirror. The photographer observes the focus plate arranged on the planned image formation plane via the finder optical system, and confirms the composition for photographing and the focus state.

[0003]

However, in the conventional still camera, the image taken on the film, for example, whether the subject has closed his eyes, or the red-eye phenomenon caused by the strobe light, is difficult. It was not possible to immediately confirm whether it had occurred.

[0004] For this reason, there is a drawback that even if there is a defect in the photographed image, it is not possible to retake the image on the spot.

[0005] An object of the invention according to the present application is to make it possible to easily confirm the image state of a photographed subject on the spot, and to make a check if the photographed image is found to be defective. An object of the present invention is to provide a camera which can be easily retaken with a camera.

[0006]

According to a first aspect of the present invention, there is provided an optical path dividing means for dividing a light beam transmitted through a photographing optical system, and the optical path dividing means being disposed on a first predetermined image plane of the optical path divided by the optical path dividing means. And a photo-writing type spatial light modulation element which is arranged on the second predetermined imaging plane divided by the optical path dividing means and is observable by a finder optical system.

According to the above configuration, the image photographed and recorded on the photographing recording medium can be immediately confirmed by the light-writing type spatial light modulator, so that the image state of the photographed subject can be immediately checked. It can be easily confirmed, and if it is determined that a defect has occurred in the captured image, it can be easily retaken on the spot.

According to a second aspect of the present invention, in the first aspect, writing and erasing of an image of the light-writing type spatial light modulator are repeated during the start of a photographing preparation operation of the camera. .

According to the above configuration, when the photographer observes the viewfinder, it is possible to observe a normal subject image.

According to a third aspect of the present invention, there is provided any one of the above inventions, further comprising a photographing instruction unit having a plurality of operation strokes for instructing the photographing recording medium to photograph, and after a stroke operation at a subsequent stage of the photographing instruction unit, During the operation, the image stored in the optical writing spatial light modulator is retained.

According to the above arrangement, it is possible to display a photographed image on the viewfinder for a time desired by the photographer.

According to a fourth aspect of the present invention, there is provided any one of the above aspects, further comprising a starting means for starting a shooting preparation operation of the camera,
The start-up unit also functions as a shooting mode selection unit that selects a single-shot shooting mode and a continuous shooting mode. When the continuous shooting mode is selected by a shooting preparation operation, the image of the light-writing type spatial light modulator is displayed. It is characterized by not being held.

According to the above configuration, it is possible to confirm the subject image sequentially even during continuous shooting.

[0014]

1 to 5 show an embodiment of the present invention. FIG. 1 is an explanatory view of a layout of a camera, FIG. 2 is a structural view of an optical writing type spatial light modulator, and FIG. Figure,
FIG. 4 is an electric circuit block diagram, and FIG. 5 is a flowchart of the camera operation.

In FIG. 1, a film 2, which is a recording medium, is disposed on a first predetermined imaging plane of a taking lens 3 constituting a taking optical system of a camera. The film 2 is normally shielded from light by a shutter 9.
The exposure of the film 2 is performed in accordance with the subsequent operation (SW2) of the shutter release switch 20, which is the photographing instruction means shown in FIG. Here, the shutter release switch 20 has front and rear operation strokes.

A half mirror 4 as an optical path dividing means is disposed between the photographing lens 3 and the film 2, and reflects a part of the subject light transmitted through the photographing optical system to guide it to the finder optical system. . Here, the reflectance of the half mirror 4 is set to a predetermined value of 10% to 50%.

In FIG. 2, an optical writing type spatial light modulator (SLM) 1 includes transparent substrates 10 and 18 on which color filters 11 and 17 and transparent electrodes 12 and 16 are formed, respectively.
In between, a photoconductive layer and a light modulation layer are provided.

Α-Si as a photoconductive layer on the transparent substrate 10 side
An (amorphous silicon) layer 13 is provided, and a ferroelectric liquid crystal layer 15 is provided as a light modulation layer on the transparent substrate 18 side. Further, a dielectric reflection layer 14 is formed between the α-Si layer 13 and the ferroelectric liquid crystal layer 15. Further, the transparent substrate 18
A polarizing plate 19 is provided on the outside.

When a voltage is applied to the α-Si layer 13 and the ferroelectric liquid crystal layer 15 via the transparent electrodes 12 and 16 by the SLM driving circuit 81 shown in FIG. The voltage divided by the resistance of the dielectric liquid crystal layer 15 is applied to each layer. At this time, the SLM drive circuit 81
Is applied to the SLM1 such that the voltage applied to the SLM1 becomes lower than the threshold voltage at which the ferroelectric liquid crystal molecules are inverted. In addition, polarizing plates
When light for reading is illuminated from the transparent substrate 18 side through 19, light of a predetermined wavelength is transmitted through the color filter 17, and the ferroelectric liquid crystal molecules are modulated by the non-inverted ferroelectric liquid crystal layer 15 to obtain dielectric light. The light is reflected by the body reflection layer 14.

The reflected illumination light is modulated again by the ferroelectric liquid crystal layer 15, passes through the color filter 17, and reaches the polarizing plate 19.
At this time, the ferroelectric liquid crystal layer 15 is configured so that the polarization axis of the light modulated by the ferroelectric liquid crystal layer 15 is rotated by 90 degrees.
The illumination light is absorbed by the polarizing plate 19.

On the other hand, when the SLM 1 is irradiated with light from the transparent substrate 10 side, electric charges are generated in the region of the α-Si layer 13 where the light is irradiated, and the resistance of the α-Si layer 13 is reduced. As a result, the α-Si layer 13
Since the voltage applied to the ferroelectric liquid crystal layer 15 corresponding to the region irradiated with the light becomes larger and exceeds the threshold voltage at which the ferroelectric liquid crystal molecules are inverted, the ferroelectric liquid crystal molecules are inverted. At this time, when light for reading is illuminated from the transparent substrate 18 side via the polarizing plate 19, light of a predetermined wavelength is transmitted through the color filter 17, and the ferroelectric liquid crystal layer 15 in which the ferroelectric liquid crystal molecules are inverted. The light is reflected by the dielectric reflection film 14 without being modulated.

The reflected illumination light passes through the ferroelectric liquid crystal layer 15 again, passes through the color filter 17 and reaches the polarizing plate 19. At this time, since the illumination light is not modulated by the ferroelectric liquid crystal layer 15, it passes through the polarizing plate 19 and exits.

By the way, even if the voltage application to the SLM 1 is cut off by the SLM driving circuit 81, the orientation of the liquid crystal molecules is preserved by the hysteresis characteristic of the ferroelectric liquid crystal 15. for that reason,
Even when no voltage is applied to the SLM1, the image once written can be stored for a long time. Also, by applying a voltage having a polarity opposite to that of image writing between the transparent electrodes 12 and 16,
It is possible to delete an image once stored.

In FIG. 1, the subject image stored in the SLM 1 disposed on the second predetermined image forming plane of the photographing optical system is turned on by a fluorescent lamp 5 for readout illumination, so that a photographer can be photographed through a finder optical system. Observable.

The operation of the camera will be described below with reference to the flowchart of FIG.

When the photographer sets the main switch 21 which is the starting means of the camera to the "on" starting state (# 100), the CPU 80 which is the camera controlling means detects the state via the signal input circuit 84, A signal is sent to the SLM driving circuit 81 to start continuous driving in which writing and erasing of a subject image are repeatedly performed in the SLM 1 (# 102). The SLM drive circuit 81 applies a write and erase pulse to the SLM 1 at a cycle of, for example, 60 Hz.

When a write pulse is applied to the SLM 1 arranged on the second predetermined imaging plane of the photographing optical system, the projection lens 3
Is reflected by the half mirror 4 and is stored in the SLM 1.

Further, the CPU 80 sends a signal to the fluorescent lamp lighting circuit 82 to light the fluorescent lamp 5 for SLM1 illumination (# 10
3). Illumination light from the fluorescent lamp 5 is applied to a penta roof prism 7
Illuminate the SLM1 via.

The subject image stored in the SLM 1 reaches the photographer's eyes via the penta roof prism 7 and the eyepiece 8, which constitute a finder optical system, as reflected light of illumination light. That is, for example, by observing the subject image written to the SLM 1 at a cycle of 60 Hz through the finder optical system, the photographer can confirm the photographing composition and the focus state.

If the photographer does not operate the front stage of the shutter release switch 20 which is the photographing instruction means (# 104), SLM1
The writing and erasing of the subject image in are repeated.
On the other hand, if the photographer operates the previous stage (SW1) of the shutter release switch 20 (# 104), the CPU 80 sets the signal input circuit.
The state is detected via 84, and a signal is sent to a focus detection circuit 86 to perform focus detection.

Further, the taking lens 3 is driven by the lens driving circuit 87 based on the detected focus detection signal. When the focus state of the taking lens 3 is adjusted, the CPU 80 sends a signal to the photometric circuit 85 to perform photometry, and uses the photometric value to calculate the CP.
U80 calculates an appropriate exposure value (# 105).

If the photographer operates the second stage (SW2) of the shutter release switch 20 (# 106), the CPU 80 detects the state via the signal input circuit 84 and outputs a signal to the shutter drive circuit.
A signal is sent to 88 to cause the shutter 9 to run.

While the shutter 9 is open, the film 2 arranged on the first predetermined imaging plane of the photographing optical system is exposed to the subject light (# 107).

When the film 2 is exposed by subject light,
The CPU 80 sends a signal to the film feeding circuit 83 to change the film to one.
It feeds the pieces (# 108). At this time, if the main switch 21 also serving as the shooting mode selection means is set to the single shooting mode which is not the continuous shooting mode (# 109), the CPU 80 sends a signal to the SLM drive circuit 81 and writes the signal to the SLM1. The deletion of the image is stopped, and an image equivalent to the captured subject image is held on the film 2 (# 110).

If the photographer continues to operate the preceding stage (SW1) of the shutter release switch 20 (# 111), the image written in the SLM1 is retained (# 110), and the photographer can use the viewfinder optical system. It is possible to confirm an image equivalent to the subject image photographed on the film 2.

If the user releases the shutter release switch 20 after confirming the image of the object photographed on the film 2 (# 111), the CPU 80 detects the state via the signal input circuit 84, and the SLM driving circuit A signal is sent to 81 to cause SLM1 to continue writing and erasing of the subject image (# 102).

By the way, if the main switch 21 also serving as the photographing mode selecting means is set to the continuous photographing mode (#
109), while the subsequent stage (SW2) of the shutter release switch 20 is being operated, the exposure of the film 2 (# 107) and the film 2
(# 108) is repeatedly executed. At this time, SLM1
Is not retained. That is, in the continuous shooting mode, the image written in the SLM 1 is not held, so that it does not hinder the confirmation of the subject during the continuous shooting.

When the photographer finishes shooting and releases the activation of the camera by the main switch 21 (# 101), the CPU 80 detects the state through the signal input circuit 84 and sends a signal to the fluorescent lamp lighting circuit 82. Turn off the fluorescent lamp 5
(# 112), a signal is sent to the SLM drive circuit 81 to stop driving the SLM1 (# 113).

In this embodiment, the image is held in the SLM 1 after the shutter release switch 20 (SW 2).
Although the example in which the operation is performed during the preceding stage (SW1) operation after the operation has been described, a configuration in which the predetermined period is maintained after the subsequent stage (SW2) operation may be employed.

[0040]

According to the first aspect of the present invention, it is possible to immediately confirm the image photographed and recorded on the photographing recording medium by the light-writing type spatial light modulator, and the image state of the photographed subject is obtained. Can be easily confirmed on the spot, and if it is determined that a defect has occurred in the captured image, it can be easily retaken on the spot.

According to the second aspect of the present invention, the photographer can observe a normal subject image during viewfinder observation.

According to the third aspect of the present invention, a photographed image can be displayed on the viewfinder for a time desired by the photographer.

According to the fourth aspect of the present invention, it is possible to sequentially confirm the subject image even during continuous shooting.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of a camera according to a first embodiment of the present invention.

FIG. 2 is a diagram showing a configuration of a spatial light modulator of FIG. 1;

FIG. 3 is an external perspective view of the camera shown in FIG. 1;

FIG. 4 is an electric circuit block diagram of the camera of FIG. 1;

FIG. 5 is a flowchart showing the operation of the camera of FIG. 1;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... SLM 2 ... Film 3 ... Projection lens 4 ... Half mirror 5 ... Fluorescent lamp 6 ... Reflection shade 7 ... Penta roof prism 8 ... Ocular lens 9 ... Shutter 10, 18 ... Transparent substrate 11, 17 ... Color filter 12, 16 ... Transparent electrode 13 α-Si layer 14 dielectric reflection layer 15 ferroelectric liquid crystal layer 19 polarizing plate 20 shutter release switch 21 main switch

Claims (4)

[Claims] An optical path splitting means for splitting a light beam transmitted through an imaging optical system; an imaging recording medium arranged on a first predetermined image forming plane of an optical path split by the optical path splitting means; And a light-writing type spatial light modulation element which is arranged on a second predetermined imaging plane divided by the optical system and which can be observed by a finder optical system. 2. The camera according to claim 1, wherein writing and erasing of an image of the optical writing type spatial light modulator are repeated during a start of a shooting preparation operation of the camera. 3. An optical writing type spatial light source comprising: a plurality of operation strokes for instructing the photographing recording medium to perform photographing; and during a preceding stage operation operation after a subsequent stroke operation of the photographing instruction unit. 3. An image stored in the modulation element is held.
The camera according to. 4. A start-up unit for starting a photographing preparation operation of the camera, wherein the start-up unit also serves as a photographing mode selecting unit for selecting a photographing mode of a single photographing and a continuous photographing. When the mode is selected,
The camera according to claim 1, 2 or 3, wherein the image of the optical writing type spatial light modulator is not held.