JP2012068310A - Observation optical system and optical equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an observation optical system capable of performing display with high visibility by combining light emitting property and light attenuating property.SOLUTION: An observation optical system includes: a first display member arranged in the vicinity of an observation surface between the observation surface and an eyepiece optical system; a beam splitter arranged between the first display member and the eyepiece optical system; and a second display member arranged via the beam splitter. The ion optical system is configured so that an image by the first display member is not displayed by transmitting observation luminous fluxes from the observation surface to the eyepiece optical system and is displayed by diffusing the observation luminous fluxes from the observation surface, and an image by the second display member of a small display shape is displayed via the beam splitter in the vicinity of the image by the first display member on the observation surface.

Description

  The present invention relates to display means for an observation optical system.

  In a conventional observation optical system, a microprism and engraving lines are arranged near the observation surface, the selection range is indicated by the engraving lines, illumination light is given to the microprisms, and the illumination light is reflected to the eye side so that the selected location is selected. In addition, the reflective area is surrounded by a frame line, and the reflective area is reflected to display the selected portion (see, for example, Patent Document 1).

JP 2004-85841 A

  In the display method, since the microprism emits light with illumination light, it becomes possible to obtain high visibility in the display of the selected location. However, since the reflection area and the marking are fixed near the observation surface, the reflection area and the marking are always visible on the field-of-view image even when the selection range is not displayed, which makes it difficult to see the observation image. It was. This became a significant problem as the location and range to be displayed in the observation field expanded. In order to improve the above problem, a transmissive liquid crystal is arranged in the vicinity of the observation surface, the observation light beam is shielded by diffusion, an image of the display member is displayed on the observation image, and only the observation light beam is transmitted when not displayed. In addition, a method has been proposed in which the image of the display member is completely invisible and the image of the display member is illuminated by putting illumination light inside the liquid crystal. However, in the above proposal, when the observation image is dark, the visibility of the image of the display member is poor, and even if the illumination light is introduced to illuminate the image of the display member, the illumination light is scattered by the liquid crystal and the visibility improvement effect Was small. Therefore, an object of the present invention is to provide an observation optical system capable of displaying with high visibility.

  An observation optical system for observing an image formed on the observation surface, and an eyepiece optical system for observing the image formed on the observation surface, and disposed near the observation surface between the observation surface and the eyepiece optical system And a first display member having means for transmitting and blocking the observation light beam from the observation surface, a beam splitter disposed between the first display member and the eyepiece optical system, and a first display member disposed via the beam splitter. The image by the first display member displayed on the observation surface is hidden by the transmission / shielding means transmitting the observation light beam from the observation surface to the eyepiece optical system. Displayed by the light shielding means shielding the observation light beam from the observation surface, and displaying smaller than the display shape of the image by the first display member via the beam splitter in the vicinity of the image by the first display member on the observation surface. An image of the second display member of the shape is displayed Configured so that.

  The image by the second display member is displayed near the center of the display shape by the image of the first display member, and the display size of the image by the second display member is the display size of the image by the first display member. It is preferable that it is 1/4 or less.

  It is preferable that a part of the eyepiece lens constituting the eyepiece optical system is disposed between the beam splitter and the eye point.

  It is preferable that at least one of the image by the first display member and the image by the second display member is used as an image for displaying the autofocus area.

  It is preferable that at least one of the image by the first display member and the image by the second display member is used as an image for displaying the photometric area.

  It is preferable that at least one of the image by the first display member and the image by the second display member is used as an image for displaying person recognition.

  As described above, it is preferable to apply an observation optical system for displaying an image formed by the first display member and the second display member so as to overlap the observation image, to the optical apparatus.

  According to the present invention, it is possible to provide an observation optical system capable of displaying with high visibility.

It is a schematic block diagram of an observation optical system. It is an example which shows an observation visual field. (A) is another example which shows an observation visual field, (b) is another example which shows an observation visual field. It is a schematic block diagram which applies an observation optical system to a single-lens reflex camera.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. A single-lens reflex camera 1 provided with an observation optical system 20 according to the present invention is shown in FIG. The single-lens reflex camera 1 includes an objective lens 11, a mirror 12, an imaging element 13 for photographing, and an observation optical system 20 that is a viewfinder. In addition, the observation optical system 20 includes a focusing screen 21 (observation surface 21), a first display member 30, a pentaprism 23, a beam splitter 40, and an eyepiece that are arranged in order from the object side along the optical axis. 25, and an image formed (imaged) on the focusing screen 21 (observation surface 21) by the objective lens 11 can be observed by the eyepiece lens 25. The second display member 42 is configured to enter the beam splitter 40 through the condenser lens 41. Further, an eye point EP is provided behind the pentaprism 23, the beam splitter 40, and the eyepiece lens 25.

  The objective lens 11 forms a subject image on the image sensor 13 or the focusing screen 21 (observation surface 21). The mirror 12 is inserted at an angle of 45 degrees with respect to the optical axis passing through the objective lens 11, and in a normal state (in a shooting standby state), light from a subject (not shown) passing through the objective lens 11 is received. The light is reflected to form an image on the focusing screen 21 (observation surface 21), and when the shutter is released, the mirror is raised and jumps up, and light from a subject (not shown) passing through the objective lens 11 is condensed on the image sensor 13. It has come to image. That is, the image sensor 13 and the focusing screen 21 (observation surface 21) are disposed at optically conjugate positions.

  In the pentaprism 23, a light beam from a subject image (an inverted image) on the focusing screen 21 (observation surface 21) formed by the objective lens 11 is incident on the incident surface 23a, the first reflecting surface 23b, the final reflecting surface 23c, and the exit surface. Through the surface 23d in order, the subject image is inverted vertically and horizontally to make an erect image. As a result, the pentaprism 23 enables the observer to observe the subject image as an erect image, and allows the observation optical system 20 to be configured in a compact manner.

  FIG. 1 is a diagram showing an embodiment of an observation optical system. When the embodiment in which the observation optical system shown in FIG. 4 is applied to a single-lens reflex camera is compared with the embodiment of the observation optical system shown in FIG. 1, the pentaprism used in the embodiment in FIG. 1 is not used in the embodiment of FIG. 1, and in the embodiment of FIG. 4, an image formed on the focal plane of the focusing screen 21 by the objective lens 11 is observed as an observation image by the eyepiece 25. The first embodiment is different in that an observation image 27 formed on the observation surface 21 is observed by the eyepiece lens 25.

  In the embodiment of FIG. 1, the first display member 30 is disposed near the observation surface 21 (between the focusing screen 21 and the pentaprism 23 in the embodiment shown in FIG. 4). Specifically, it is effective to use a transmissive liquid crystal element or the like for the first display member 30. The display direction is changed by changing the arrangement direction of the liquid crystal according to the voltage and diffusing and shielding the light beam in the observation visual field that transmits the set selection range. In order to shield the light, the display is observed in a black shape on the observation field. Further, the first display member 30 is desirably arranged in the vicinity of the observation surface 21 in order to display a light-shielded shape. The distance between the first display member and the observation surface 21 on the eyepiece optical axis is preferably about 0 to 10% of the focal length of the eyepiece lens 25. When the upper limit is exceeded, it is difficult to recognize the display shape of the first display member on the observation visual field image, which makes it difficult to see the display shape.

  The second display member 42 has a beam splitter 40 disposed between the observation surface 21 and the eyepiece 25, and the image of the second display member 42 is converted into an observation field image via one condenser lens 41. Overlapping display. The image of the second display member 42 is displayed by emitting a display shape. Specifically, the mask shape of the display pattern is illuminated with an LED or the like to form an image of the second display member 42 having the display shape, or the display shape itself is caused to emit light by using an EL device or the like. An image of the display member 42 can also be configured. Further, in the present embodiment, it is desirable that the image display size of the second display member 42 is reduced by using the condenser lens 41 to ¼ or less of the image display size of the first display member 30. By reducing the size, the optical system including the second display member 42 can be reduced in size.

  However, if the display size of the image of the second display member 42 is smaller than 1/5, it is not desirable because the visibility decreases unless the display brightness is increased. The condensing lens 41 also needs to have a large enlargement ratio in order to enlarge the image by the second display member 42. For this reason, if the condenser lens 41 is not composed of a plurality of lenses, the aberration cannot be corrected and the appearance of the display deteriorates. Further, it is not preferable that the condenser lens 41 is composed of a plurality of lenses because the display optical system is enlarged. Furthermore, in the present embodiment, it is desirable that the beam splitter 40 be disposed at a position close to the eyepiece lens 25. By arranging in this way, the observation field light flux is converged to the eye point EP by the eyepiece lens 25, so that the size of the beam splitter 40 to be introduced can be reduced. Furthermore, the same effect can be obtained even if it is arranged inside the eyepiece lens 25 or between the eyepiece lens 25 and the eye point EP.

  Further, as the beam splitter 40 used in the present embodiment, one that reflects only a specific wavelength in accordance with illumination light such as an LED to be displayed can be used. When the wavelength of the display LED is set to a wavelength of about 650 to 700 nm, the reflection wavelength region of the beam splitter 40 corresponds to the wavelength, and the wavelength of 400 to 650 nm from the observation image including the visibility is transmitted. Even if the beam splitter 40 is arranged in the observation optical system, the color reproducibility of the field image can be kept good. Therefore, it is possible to observe without changing the color tone of the field image of the observation image between when the image of the second display member 42 is displayed and when the image is not displayed.

  And the 1st display member 30 and the 2nd display member 42 of this embodiment are used in order to display the selection range on an observation visual field, as shown in FIG. Either one of the display members displays the selection range of a, and the selection display of b performs selection display on the other display member near the display of the selection range. High visibility is achieved by displaying the selection range using two types of display, light-shielding display and light image display, which are the characteristics of the two display members.

  Furthermore, in this embodiment, what is always displayed, such as a selection range, is displayed as an image of the first display member 30, and what is relatively short in display time, such as selection, is displayed as an image of the second display member 42. desirable. Since the image of the first display member 30 is displayed by shielding the luminous flux of the field of view, the display brightness reaching the eyes is not increased by the display, and thus it is easy to observe and suitable for long-time display. The selective display projects the image of the second display member 42 to increase the brightness of the selective display with respect to the observation visual field, thereby improving the visibility of the selective display. Also, from the viewpoint of current consumption, the first display member 30 can be controlled with less power than the second display member 42, and thus is suitable for long-time display.

  By adopting such a configuration, when the selection range is not displayed, both the first display member 30 and the second display member 42 can transmit only the observation light. In the state where the image is not displayed by the second display member, only the observation image can be observed.

  As such an embodiment, as shown in FIG. 3A, a plurality of selection ranges that can be selected in advance are displayed as a by the image of the first display member 30, and information on the range that can be selected by the observer is shown. In FIG. 3B, which selection range is selected, the image by the second display member 42 is displayed in the vicinity of the image by the first display member 30 or the image by the first display member 30 as shown by b in FIG. By displaying so as to overlap the display shape, high visibility can be obtained in displaying the selection range.

  In the conventional observation optical system, since display is performed using an image by a single display member, it is difficult to display an arbitrary display range in advance with a display unit that provides engraving lines near the observation surface. In addition, since the engraved line is always visible on the observation image, there is a problem that the observation image is difficult to see. In addition, the above display example can be realized by arranging a transmissive liquid crystal in the vicinity of the observation surface and shading by diffusion. However, to display the selected part, it is only necessary to blink only the selected range and turn off the display outside the selected range. There wasn't. For this reason, blinking display and extinction are poor in response in the liquid crystal member, and there is a problem particularly at low temperatures.

  In this embodiment, the present invention can be applied to an optical system that observes the observation surface 21 with the eyepiece lens 25. In particular, the observation optical system of the present embodiment is effective for optical instruments such as cameras, binoculars, and microscopes that form a real image with an objective lens and observe the observation optical system with an eyepiece.

  According to the present embodiment, the first display member 30 disposed in the vicinity of the observation surface 21, and the beam splitter 40 is disposed between the first display member 30 and the eyepiece optical system 25, via the beam splitter. The second display member 42 is arranged. Since the image is formed by the black first display member 30 that is not displayed or displayed by transmitting the observation light beam from the observation surface 21 to the eyepiece optical system 25 or diffusing / shading it, the first display is performed. Even if the image by the member 30 is superimposed on the observation image and displayed, the observer can observe the observation image for a long time. By arranging the first display member 30 in the vicinity of the observation surface 21, the image by the first display member 30 can be visually recognized with a clear shape. The image by the second display member 42 is projected superimposed on the observation image via the beam splitter. The display shape of the image by the second display member 42 is displayed in a smaller display shape than the display shape of the image by the first display member 30. By doing so, the optical system of the second display member 42 can be reduced in size. The visibility of the observation image is displayed by displaying the image with high visibility that can be observed for a long time by the first display member 30 and the image by the second display member 42 in the vicinity of the image by the first display member 30. It is possible to superimpose two types of images with high visibility on the observation image without losing the image.

  On the observation visual field, the display shape of the image formed by the second display member 42 is set to ¼ or less of the display shape of the image displayed by the first display member 30. The condensing lens 41 for projecting the image by the second display member 42 onto the beam splitter 40 does not need to obtain a large enlargement ratio with a plurality of lenses, and can be constituted by a single lens. The optical system for displaying the two display members 42 can be made compact.

  By arranging the beam splitter in the vicinity of the eyepiece lens 25, the observation light beam passes through the beam splitter 40 and converges to the eye point EP by the eyepiece lens 25. However, since the beam splitter 40 is close to the eyepiece lens 25, the beam splitter 40 can be made compact.

  Although two types of images of the first display member 30 and the second display member 42 can be superimposed on the observation image, at least one of them displays an autofocus area. For this reason, the autofocus area can be displayed by a display with high visibility.

  Although two types of images of the first display member 30 and the second display member 41 can be superimposed on the observation image and displayed, at least one of them displays a photometric area. By using this, it is possible to display the photometric area with a highly visible display.

  Although two types of images of the first display member 30 and the second display member 42 can be displayed superimposed on the observation image, at least one of them displays person recognition. By using it, it becomes possible to display person recognition by a display with high visibility.

  As a result, according to the observation optical system of the present embodiment, the image displayed by the first display member 30 is displayed so as to overlap the observation image without increasing the display brightness reaching the eyes, so that the observer can perform the first display. The image by the member 30 can be observed in a black shape. More specifically, a plurality of images by the first display member 30 are provided, and the plurality of images are displayed in a black shape on the observation field. For example, in FIG. 3A, a plurality of images (five in FIG. 3A) are formed by the first display member. These images are used to display a plurality of candidate areas, and are displayed by the second display member 42. Since the image is a luminescent image, it can be used as a display indicating that one of a plurality of candidate areas indicated by the image by the first display member 30 has been selected.

  For example, when an area to be autofocused is selected in the observation visual field, it is as follows. It is assumed that the observer wants to perform autofocusing among the plurality of autofocus candidate areas displayed on the observation visual field in the middle left area of the plurality of areas shown in FIG. 3A. The observer operates an operation unit of a single-lens reflex camera (not shown) to display a luminescent image by the second display member 42 in the vicinity of the candidate area. When the image by the second display member 42 is displayed in the vicinity of the preferred autofocus area, the observer operates the operation unit of the single-lens reflex camera (not shown) to select the left side of the middle stage from the autofocus candidate area. Operate to confirm the area as the autofocus area. Thus, since the image by the 1st display member 30 is black shape and it is easy for an observer to observe for a long time, it is suitable for displaying a plurality of autofocus candidate areas. An image that is luminescent and highly visible by the second display member 42 is displayed in the vicinity of the image by the first display member 30, so that the observer can select one of a plurality of autofocus candidate areas. It becomes easy to confirm the selection.

  In addition, it is also possible to use the image by the 1st display member 30 in order to show the candidate area of a some photometry area. The observer operates an operation unit of a single-lens reflex camera (not shown) to display a luminescent image by the second display member 42 in the vicinity of the candidate area. When the image by the second display member 42 is displayed in the vicinity of a preferable photometry area, the observer operates an operation unit of a single lens reflex camera (not shown) to select one area from a plurality of photometry area candidate areas. To confirm as the metering area. Thus, since the 1st display member 30 is black shape, since it is easy for an observer to observe for a long time, it is easy to display the candidate area of a some photometry area. By displaying an image with high luminosity visibility by the second display member 42 in the vicinity of the image by the first display member 30, it is easy to confirm that a photometric area preferred for the observer has been selected. It becomes.

  In addition, it is also possible to use the image by the 1st display member 30 as an image for displaying the person recognition of several persons in an observation visual field. The observer operates an operation unit of a single-lens reflex camera (not shown) to display a luminescent image by the second display member 42 in the vicinity of the candidate person. When the image by the second display member 42 is displayed in the vicinity of a preferable person, the observer operates an operation unit of a single-lens reflex camera (not shown) to determine one person from among a plurality of person recognitions. Operate as follows. As described above, by using the first and second display members, it is possible to set the autofocus on the most preferable person for the observer, to measure the light according to the most preferable person, or to enlarge the vicinity of the most preferable person. It is also possible to control a single-lens reflex camera so as to shoot.

  Note that the image by the first display member 30 and the image by the second display member 42 can be used for different purposes. It is also possible to use images by the first and second display members for different purposes such as autofocus area, photometric area, person recognition, and the like. For example, the image by the first display member 30 can be used to show an autofocus area, and the image by the second display member 42 can be used to show a photometric area. Various combinations are possible for this combination, and the combination is not limited to one combination.

  Here, when the image by the first display member 30 is used to indicate an autofocus area, and the second display member 42 is used to indicate a photometric area, the autofocus area of the first display member 30 is indicated. A method for designating an area among a plurality of candidate areas is, for example, by operating an operation unit of a single lens reflex camera (not shown) so that the plurality of candidate areas are sequentially displayed in a black shape, and a preferable area is displayed. It is also possible to configure the operation unit of the single-lens reflex camera so that one of the candidate areas is determined by operating the operation unit. Similarly, a plurality of candidate areas can be sequentially displayed by the second display member 42, and when a preferred area is displayed, the area can be designated as a photometric area.

  Moreover, although the example which uses the image by the 1st display member 30 and the image by the 2nd display member 42 for person recognition other than an autofocus and photometry area was described, it uses in order to recognize the specific thing of an observation image. The case is not limited to person recognition. It can also be used for recognizing a moving object in the observation field, or for recognizing a stationary object. Alternatively, it can be used for recognition of facial expressions and recognition of specific animals. Further, it can be used for specific color recognition.

  For example, when used for recognizing facial expressions in the observation visual field, a plurality of recognized faces in the observation visual field are displayed as images by the first display member 30, and laughing at the image by the second display member 42. The control unit of the single-lens reflex camera (not shown) determines that the laughing face has been recognized by performing an operation so as to determine the face that is being displayed, and in the image of the observation field that is continuously displayed thereafter. Each time a smiling face is displayed, control can be performed so that the smiling face is captured by a control function (not shown) of the single-lens reflex camera. In this way, by displaying the image of the first display member 30, the image of the second display member 42, and the image of the two display members, various methods or various controls that have not been conventionally possible can be performed. It becomes possible.

  As an example used for specific color recognition, candidate areas are displayed by images from the first display member 30 in a plurality of areas in the observation visual field. The observer operates an operation unit (not shown) of the single-lens reflex camera to select one of a plurality of candidate areas for the image by the second display member 42. The control function (not shown) recognizes the color tone of the selected area, and it is possible to control to operate the color tone of the observation image based on the selected color recognition. Or, when capturing images continuously, based on the selected color recognition, it is possible to perform control such as capturing when an observation image having the same color as the selected color appears in the observation field. It is.

  Thus, the observation optical system of the present embodiment can superimpose two types of display by the first display member 30 and the second display member 42 on the observation image, and the first display member 30 and the second display member 42 can be used as a display for showing various purposes of the observation image or characteristics of the application. Therefore, the observation optical system shown in this embodiment is a single observation optical system. Can be applied to an observation optical system used as a finder of a single-lens reflex camera, or can be used as an observation optical system widely used in a real image optical system. Further, the above-described embodiment is merely an example, and is not limited to the above-described configuration and shape, and can be appropriately modified and changed within the scope of the present invention.

1 Single-lens reflex camera (optical equipment)
DESCRIPTION OF SYMBOLS 20 Observation optical system 21 Focal plane or observation surface 25 Eyepiece 30 First display member 40 Beam splitter 41 Condensing lens 42 Second display member EP Eye point

Claims (7)

An observation optical system for observing an image formed on an observation surface,
An eyepiece optical system for observing an image formed on the observation surface;
A first display member disposed in the vicinity of the observation surface between the observation surface and the eyepiece optical system, and having a means for transmitting and shielding the observation light beam from the observation surface;
A beam splitter disposed between the first display member and the eyepiece optical system;
A second display member disposed via the beam splitter,
The image by the first display member displayed on the observation surface is not displayed when the transmission / light shielding unit transmits the observation light beam from the observation surface to the eyepiece optical system. Is displayed by shielding the observation light beam from the observation surface,
An image of the second display member having a display shape smaller than the display shape of the image by the first display member is displayed through the beam splitter in the vicinity of the image by the first display member on the observation surface. An observation optical system configured to be configured as described above.   The image by the second display member is displayed at a position near the center of the display shape by the image of the first display member, and the display size of the image by the second display member is the image by the first display member. The observation optical system according to claim 1, wherein the display optical system has a display dimension of ¼ or less.   3. The observation optical system according to claim 1, wherein a part of an eyepiece constituting the eyepiece optical system is disposed between the beam splitter and an eye point.   The image according to claim 1, wherein at least one of the image by the first display member and the image by the second display member is used as an image for displaying an autofocus area. Observation optical system.   The observation according to claim 1, wherein at least one of the image by the first display member and the image by the second display member is used as an image for displaying a photometric area. Optical system.   The observation according to claim 1, wherein at least one of the image by the first display member and the image by the second display member is used as an image for displaying person recognition. Optical system.   An optical apparatus comprising the observation optical system according to any one of claims 1 to 6.

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