JP6285112B2 - Light splitter - Google Patents

Description

  The present invention relates to a light splitting device that splits external light to form an image.

  In technical fields such as life science, observation light (for example, fluorescence) from a sample is dispersed according to wavelength, and as a result, a plurality of dispersed light images are observed. For example, the following Non-Patent Document 1 discloses a dual-view microscopy technique using one camera, and this technique uses a light splitting assembly that is attached to the outside of the microscope body. The light splitting assembly includes two dichroic mirrors provided between a pair of lenses that project an intermediate image formed by a microscope onto a camera, and two mirrors adjacent to the two dichroic mirrors. .

  With such a light splitting assembly, observation light formed by a microscope can be simultaneously observed as two types of light images having different wavelength components. Furthermore, in the above light splitting assembly, if the dichroic mirror is removed and the position of the camera is shifted, it can be used for conventional single light image microscopy.

K. Kinosita, Jr. et al., “DualView Microscopy with a Single Camera: Real-Time Imaging of Molecular Orientations and Calcium”, The Journal of Cell Biology, Volume 115, Number 1, October 1991, pp67-73

  However, in the above-described conventional light splitting assembly, when it is desired to change from the mode for observing two types of light images to the mode for observing a single light image, it is necessary to move the camera fixed to the light splitting assembly. There is. For this reason, movement of a relatively heavy camera tends to make the balance of the entire apparatus unstable, and it may be difficult to adjust the position of the camera.

  Therefore, the present invention has been made in view of the above problems, and provides a light splitting device that facilitates a setting operation when changing the observation mode and easily stabilizes the balance of the entire device. With the goal.

  In order to solve the above-described problem, a light splitting device according to an embodiment of the present invention includes a field stop for limiting a field range on an imaging plane of observation light from the outside, and observation light that has passed through the field stop. The collimator lens that receives and converts the observation light into parallel light and outputs the collimated light, and is arranged on the optical axis of the collimator lens, transmits the parallel light and outputs it as the first split light, and reflects the parallel light. A beam splitter that outputs the second split light, a reflective optical element that reflects the second split light output from the beam splitter, and a first optical output that is output from the beam splitter, disposed on the optical axis of the collimator lens. A first optical image is output by imaging one split light, and a second optical image is output by imaging the second split light output from the beam splitter via the reflective optical element. Output Comprising an imaging lens, an imaging lens moving mechanism for moving in a direction intersecting the imaging lens to the optical axis of the collimator lens, the.

  According to such a light splitting device, the observation light that has passed through the field stop is converted into parallel light by the collimator lens, and the parallel light is split into the first and second split light by the beam splitter and output. The first divided light is imaged by the imaging lens and output as a first optical image, and the second divided light is reflected by the reflective optical element and then imaged by the imaging lens to be the second light. Output as an image. Thereby, observation light can be simultaneously output as two light images, and two images of a sample can be observed simultaneously. At this time, since the position of the imaging lens is configured to be movable in a direction crossing the optical axis of the collimator lens, a mode for dividing the observation light of the sample into two optical images, and the observation light of the sample as one When switching between the modes for outputting as an optical image, the position of the imaging lens can be changed to adjust the imaging position of the optical image on the light receiving surface of the optical image. As a result, the setting operation at the time of mode switching can be facilitated, and the balance of the entire apparatus before and after mode switching can be stabilized.

  Here, the imaging lens moving mechanism is configured such that when the imaging magnification by the collimator lens and the imaging lens is m and the width in the direction perpendicular to the optical axis of the collimator lens of the field stop is w, the light of the imaging lens It is preferable that the axis is configured to move so as to deviate by more than m × w / 2 from the optical axis of the collimator lens. By adopting such a configuration, it is possible to reliably prevent the first and second light images formed on the light receiving surface from overlapping on the light receiving surface.

  It is also preferable that the imaging lens moving mechanism is configured to move the optical axis of the imaging lens so that it deviates by about m × w / 2 from the optical axis of the collimator lens. In this case, since the first and second light images formed on the light receiving surface are arranged close to each other on the light receiving surface, the two light images of the sample are efficiently observed using the light receiving surface effectively. be able to.

  Furthermore, it is also preferable that the field stop is configured so that the width in the direction perpendicular to the optical axis of the collimator lens can be variably set. In this way, when the observation light is switched between a mode in which the observation light of the sample is divided into two light images and a mode in which the observation light of the sample is output as one light image, the light receiving surface is effectively used to efficiently perform the observation. Can be observed. Specifically, in the mode that divides into two light images, the width of the field stop is reduced, and in the mode that outputs one light image, the width of the field stop is increased, so that a wider range of the light receiving surface can be observed. Can be used.

  Furthermore, it is also preferable that the beam splitter is constituted by a dichroic mirror. In this way, the observation light can be output simultaneously as light images in two different wavelength ranges, and images of different wavelength ranges of the sample can be observed simultaneously.

  Furthermore, the image pickup device further includes an image pickup device having a light receiving surface at an image forming position of the first and second optical images output from the image forming lens, the image forming magnification by the collimator lens and the image forming lens is m, and the light receiving surface. It is also preferable that when the width in the direction perpendicular to the optical axis of the collimator lens is wc, the width w in the direction perpendicular to the optical axis of the collimator lens of the field stop is set to wc / (2 × m). It is. According to such a configuration, the imaging range of the first and second optical images can be separated and arranged over the entire light receiving surface, so that the sample image can be observed more efficiently by effectively using the light receiving surface. can do.

  The beam splitter is configured to be detachable from the optical axis of the collimator lens, and the imaging lens moving mechanism is configured so that the imaging lens has a first optical axis that coincides with the optical axis of the imaging lens. It is also preferable that the imaging lens is configured to be movable so that it is in one of the state 1 and the second state in which the optical axis of the imaging lens is shifted from the optical axis of the collimator lens. . With this configuration, when the observation light of the sample is switched between a mode in which the observation light of the sample is divided into two light images and a mode in which the observation light of the sample is output as one light image, the light is efficiently applied to the light receiving surface. An image can be formed. Specifically, when observing one light image, the light image is formed at the center of the light receiving surface, and when observing two light images, the two light images are separated and formed on the light receiving surface. Can be made.

  Furthermore, in one embodiment of the present invention, a second reflective optical element that further reflects the second split light that has passed through the reflective optical element and an optical axis of the collimator lens are output from the beam splitter. And a second beam splitter that transmits and outputs the first split light and reflects and outputs the second split light that has passed through the second reflective optical element. The first split light output from the second beam splitter is imaged to output a first light image, and the second split light output from the second beam splitter is imaged to generate the first light image. It is also possible to output two optical images.

  According to the present invention, it is possible to provide a light splitting device that facilitates the setting operation when changing the observation mode and can easily stabilize the balance of the entire device.

It is a perspective view which shows the internal structure of the light splitting optical apparatus 1 of one Embodiment of this invention. It is a figure which shows the spectral state of the two optical images in the light division | segmentation optical apparatus 1 of FIG. FIG. 2 is a diagram showing an image of a light image formed on a light receiving surface 102a of a camera device 101 by the light splitting optical device 1 of FIG. It is a perspective view which shows the internal structure of 1 A of light splitting optical apparatuses which concern on the modification of this invention. FIG. 5 is a diagram illustrating a spectral state of two light images in the light splitting optical device 1 </ b> A of FIG. 4. It is a perspective view which shows the internal structure of the light splitting optical apparatus 1B which concerns on another modification of this invention. FIG. 7 is a diagram illustrating a spectral state of two light images in the light splitting optical device 1 </ b> B of FIG. 6. It is a perspective view which shows the internal structure of 1 C of light division | segmentation optical apparatuses which concern on another modification of this invention. FIG. 9 is a diagram illustrating a spectral state of two light images in the light splitting optical device 1 </ b> C of FIG. 8.

  Embodiments of a light splitting device according to the present invention will be described below in detail with reference to the accompanying drawings. In the description of the drawings, the same elements are denoted by the same reference numerals, and redundant description is omitted. Each drawing is made for the purpose of explanation, and is drawn so as to particularly emphasize the target portion of the explanation. Therefore, the dimensional ratio of each member in the drawings does not necessarily match the actual one.

  FIG. 1 is a perspective view showing an internal configuration of a light splitting optical device 1 according to an embodiment of the present invention. The light splitting optical device 1 according to the present embodiment is attached to an external observation light forming device such as a microscope device, and splits the observation light of the sample input from the observation light forming device by the wavelength component. This is an optical system that forms an optical image of two divided wavelength components on the light receiving surface of an image sensor in the attached camera.

  As shown in the figure, a light splitting optical device 1 includes a collimator lens 3, an imaging lens 4, a front stage dichroic mirror (beam splitter) 5a, a rear stage dichroic mirror (second beam splitter) 5b, in a housing 2. A front stage mirror (reflection optical element) 6a, a rear stage mirror (second reflection optical element) 6b, a correction lens 7, and an imaging lens moving mechanism 8 are built in. Hereinafter, the configuration of each component of the light splitting optical device 1 will be described in detail.

A circular field stop 9 is provided at the center of the end surface on one end side of the cylindrical portion 2a constituting a part of the housing 2. The field stop 9 has a stop adjusting mechanism 14 whose inner diameter (width) can be variably set. Then, collimator lens 3, the central axis of the optical axis L ₁ is cylindrical portion 2a, i.e., to match the central axis of the field stop 9 is fixed to the inside of the other end of the cylindrical portion 2a. This structure, field stop 9 is to be set to the width in the direction perpendicular variable with respect to the optical axis L _1. Then, the end surface of the cylindrical portion 2a of the housing 2 is attached to the microscope apparatus, is input to the interior of the housing 2 along the optical axis L ₁ from a sample of the observation light field stop 9 formed by the microscope apparatus . The collimator lens 3 receives the observation light that has passed through the field stop 9, converts the observation light into parallel light, and outputs the parallel light along the optical axis L ₁ inside the housing 2. By adjusting the aperture of the field stop 9, it is possible to limit the field range on the imaging plane of the observation light from the sample.

A cylindrical portion 2b positioned coaxially with the cylindrical portion 2a is integrally formed on the opposite side of the cylindrical portion 2a of the housing 2, and a cylindrical portion is formed at the center of the end surface of the cylindrical portion 2b. A circular window portion 10 is provided for allowing an optical image formed based on the observation light input from the 2a side to pass outside. And the camera apparatus 101 is attached to the end surface of the cylindrical part 2b of this housing | casing 2. FIG. The camera device 101 includes an image sensor 102, the light receiving surface 102 a of the image sensor 102 faces the window portion 10, the center of the light receiving surface 102 a is located on the optical axis L ₁ of the collimator lens 3, and The surface 102a is attached so as to coincide with the imaging position of the optical image output from the window portion 10. With such an attachment structure, a light image formed by the light splitting optical device 1 is picked up by the camera device 101 in a state where the light splitting optical device 1 and the camera device 101 are coaxially arranged with respect to the microscope device. Is made possible.

Further, the cylindrical portion 2a, on the inside of the optical axis L ₁ of the housing 2 between the 2b are front dichroic mirrors 5a and subsequent dichroic mirror 5b is disposed so as to be detachable. These dichroic mirrors 5 a and 5 b are integrated and configured to be detachable from the optical axis L ₁ in the housing 2. Note that the dichroic mirrors 5a and 5b may be integrated with a later-described front-stage mirror 6a, a rear-stage mirror 6b, and a correction lens 7 to be detachable.

Front dichroic mirrors 5a, at a position adjacent to the collimator lens 3, the optical axes L ₁ the center is located on, and arranged so the light receiving surface thereof is inclined 45 degrees relative to a plane orthogonal to the optical axis L ₁ Has been. This first-stage dichroic mirror 5a spectroscopically transmits and transmits the light in a predetermined first wavelength region (hereinafter referred to as “first divided light”) of the parallel light output from the collimator lens 3. and outputs along the first split beam to the optical axis L _1. At the same time, the pre-stage dichroic mirror 5a spectroscopically reflects and reflects the light of a predetermined second wavelength region different from the first wavelength region of the parallel light (hereinafter referred to as “second divided light”), and the second dichroic mirror 5a output in a direction perpendicular (downward direction in FIG. 1) the split light to the optical axis L _1.

Subsequent dichroic mirror 5b, at a position spaced to the window portion 10 side from the front dichroic mirrors 5a, the center is shifted by a predetermined distance downstream mirror 6b side from the optical axis L _1, and the light receiving surface thereof is the optical axis L ₁ It is arranged so as to be inclined by 45 degrees with respect to the orthogonal plane. The rear stage dichroic mirror 5b is composed of an optical member having the same wavelength transmission characteristics and wavelength reflection characteristics as the front stage dichroic mirror 5a, and further transmits the first divided light that has passed through the front stage dichroic mirror 5a. to output toward the window 10 along the split light to the optical axis L _1. At the same time, the rear-stage dichroic mirror 5b reflects the second split light that has been reflected by the front-stage mirror 6a, the correction lens 7, and the rear-stage mirror 6b after being reflected by the front-stage dichroic mirror 5a. and outputs toward the window 10 along the direction inclined with respect to the axis L _1.

  That is, these dichroic mirrors 5a and 5b are beam splitters that divide parallel light from the collimator lens 3 into first and second divided lights. A polarization beam splitter may be used as the beam splitter that divides the light into the first and second divided lights. Thereby, it becomes possible to divide | segment into 1st and 2nd split light by a polarization component. A half mirror may be employed as the beam splitter.

Front mirror 6a are provided spaced from the front dichroic mirror 5a to the second reflection direction of the split light, the angle of the light receiving surface of the front mirror 6a is 45 degrees inclined with respect to a plane orthogonal to the optical axis L ₁ It is set to be. The front mirror 6a reflects the second split light output from the previous stage dichroic mirror 5a in the direction parallel to the optical axis L _1. The rear stage mirror 6b is provided so as to be separated from the front stage mirror 6a in the reflection direction of the second split light and to face the light receiving surface of the rear stage dichroic mirror 5b. The angle of the light receiving surface of the rear stage mirror 6b is determined by the optical axis L. _It is set to be inclined by 45 + α degrees (α is a preset angle) with respect to _one orthogonal plane. The subsequent mirror 6b is reflected toward the light receiving surface of the subsequent dichroic mirror 5b along a direction intersecting the second divided light through the front mirror 6a to the optical axis L _1. The correction lens 7 is disposed between the front-stage mirror 6a and the rear-stage mirror 6b, and has a function of performing magnification correction and color correction of the second divided light.

Further, on the optical axis L ₁ between the rear stage dichroic mirror 5 b and the window portion 10, the imaging lens 4 supported by the imaging lens moving mechanism 8 so that the position can be adjusted is provided. The image forming lens 4, the optical axis L ₂ is supported so as to be parallel to the optical axis L _1, the imaging lens moving mechanism 8, the optical axis L ₂ is a parallel to the optical axis L ₁ and it is movable in a direction perpendicular to the optical axis L ₁ while maintaining. Specifically, the image forming lens 4, the imaging lens moving mechanism 8, a first state in which the optical axis L ₂ is coincident with the optical axis L _1, the optical axis L ₂ by a predetermined distance A from the optical axis L ₁ It can be set to the shifted second state. At this time, the center of the rear stage dichroic mirror 5 b is positioned on the optical axis of the imaging lens 4. Thereby, vignetting can be reduced. Such an imaging lens moving mechanism 8 may be a slide mechanism capable of continuously adjusting the position of the imaging lens 4 or switched to a position corresponding to the first and second states in two stages. A switching mechanism may be used. When the imaging lens 4 is set in the second state by the imaging lens moving mechanism 8, the imaging lens 4 receives the first and second divided lights divided from the observation light via the dichroic mirrors 5a and 5b. Then, the divided light is formed as first and second light images separated on the light receiving surface 102a in the camera device 101 attached to the outside of the window portion 10. On the other hand, the imaging lens 4 is set to the first state by the imaging lens moving mechanism 8, and when the dichroic mirrors 5a and 5b are removed, the observation light is received only through the collimator lens 3, The observation light is formed as a single light image on the light receiving surface 102a in the camera apparatus 101 attached to the outside of the window portion 10.

  In the light splitting optical device 1 having such a configuration, an observation mode (hereinafter referred to as “single view mode”) in which observation light is observed with a single light image by the camera device 101, and observation light by the camera device 101. It can be used both as an observation mode (hereinafter referred to as “double view mode”) in which observation is performed separately into two light images.

  Next, with reference to FIG. 2, a mechanism for separating two light images output when the light splitting optical apparatus 1 is used in the double view mode will be described.

The observation light beam B ₁ input from the field stop 9 is collimated by the collimator lens 3, and then the first split light B ₂ is split from the parallel light by the dichroic mirrors 5 a and 5 b, and the optical axis. It is input to the image forming lens 4 along the L _1. Since the optical axis L _{2 of the} imaging lens 4 is shifted from the optical axis L ₁ by a predetermined distance A, the first split light B _{2 that} has passed through the imaging lens 4 has a deviation amount A and Corresponding to the shift direction, the image is formed at a position shifted from the center on the light receiving surface 102a of the camera device 101 (for example, the position of the lower half of the light receiving surface 102a shown in FIG. 2). This is because the asymmetrical light is input with respect to the optical axis L ₁ relative to the image forming lens 4. At the same time, after the parallel light output from the collimator lens 3 is divided into second split light B ₃ by the dichroic mirror 5a, the second split light B ₃ are dichroic mirrors 5b from via mirrors 6a, and 6b And is input to the imaging lens 4. At this time, the inclination angle with respect to a plane orthogonal to the optical axis L ₁ of the subsequent mirror 6b is set to 45 + alpha degree, the position of the subsequent dichroic mirror 5b is placed offset from the optical axis L ₁ in the same direction as the imaging lens 4 since it is, the second split light B ₃ is incident on the imaging lens 4 along the direction oblique to the optical axis L _1. Imaging result, the second split light B ₃ passed through the imaging lens 4, corresponding to the position of the tilt angle and subsequent dichroic mirror 5b of the subsequent mirror 6b, from the center on the light receiving surface 102a of the camera device 101 The image is formed at a position shifted in the direction opposite to the direction in which the lens 4 is shifted (for example, the position of the upper half of the light receiving surface 102a shown in FIG. 2). Accordingly, the first and second light images formed by the first and second divided lights can be separated and arranged on the light receiving surface 102a.

  Here, in the light splitting optical device 1, preferred values for the set value of the deviation amount A of the imaging lens 4 and the inner diameter of the field stop 9 in the second state when used in the double view mode will be described. FIG. 3 is a diagram illustrating an image of a light image formed on the light receiving surface 102 a of the camera device 101 by the light splitting optical device 1.

The shift amount A of the imaging lens 4 in the second state is such that the imaging magnification by the collimator lens 3 and the imaging lens 4 is m, and the inner diameter of the field stop 9 (the direction in which parallel light is reflected by the front dichroic mirror 5a ( When the width (in the downward direction in FIG. 1) is set to w, A ≧ m × w / 2 is set. In other words, the imaging lens moving mechanism 8 is configured so that the position of the imaging lens 4 can be adjusted so that the optical axis L ₂ of the imaging lens 4 is shifted from the optical axis L ₁ by m × w / 2 or more. The The reason for this is as follows. If you want containing two optical image split into the light receiving surface 102a of the image sensor 102, the inner diameter w of the field stop 9 is a direction perpendicular to the optical axis L ₁ of the light receiving surface 102a, collimated by front dichroic mirror 5a When the width in the direction in which light is reflected (the lower direction in FIG. 1) is wc, w ≦ wc / (2 ×) so that the width of one light image is half or less of the width wc of the light receiving surface 102a. m). In order to prevent two light images from overlapping on the light receiving surface 102a, the center of the light image in the double view mode is shifted from the center of the light receiving surface 102a that is the center of the light image in the single view mode. It is necessary to set the amount to ½ or more of the width of the optical image formed on the light receiving surface 102a. FIG. 3B shows an image of a light image formed on the light receiving surface 102a when the shift amount A of the imaging lens 4 and the inner diameter of the field stop 9 are set within the above-described preferable values. Yes. In this case, it is set to one displacement amount A two light images G _1, G ₂ do not overlap the range to the center C ₁ of the optical image G ₁ double view mode from the center C ₀ of the light receiving surface 102a become. In this case, however, the deviation A of the imaging lens 4 has a predetermined value corresponding to the inner diameter of the field stop 9 so that the two optical images G ₁ and G ₂ do not protrude from the end of the light receiving surface 102a. It is set not to exceed.

Furthermore, when the light receiving area of the light receiving surface 102a is used to the maximum, the inner diameter w in the direction in which parallel light is reflected by the front dichroic mirror 5a of the field stop 9 (downward in FIG. 1) is a direction perpendicular to the optical axis L _1, when the width direction (downward direction in FIG. 1) to parallel light by the front dichroic mirror 5a is reflected is wc, the width of one light image of the light receiving surface 102a W = wc / (2 × m) is set so as to be half of the width wc. In addition, the shift amount A of the imaging lens 4 in the second state is set as A = m × w / 2. In other words, the image forming lens moving mechanism 8 is configured so that the position of the image forming lens 4 can be adjusted so that the optical axis L ₂ of the image forming lens 4 is shifted from the optical axis L _{1 by} about m × w / 2. The FIG. 3A shows an image of a light image formed on the light receiving surface 102a when the shift amount A of the imaging lens 4 and the inner diameter of the field stop 9 are set within the above-mentioned preferable value range. Yes. In this case, the range shift amount A from the center _{C 0} of the light receiving surface 102a to the center _{C 1} of the optical image _{G 1} double view mode is, the two optical images _G 1, _{G 2} are divided by two of the light receiving surface 102a Will be set to a value that does not overlap.

Furthermore, the setting condition of the inclination angle 45 + α degrees of the rear stage mirror 6b for accommodating two light images on the light receiving surface 102a in the double view mode will be described. Optical axis L ₁ in a direction perpendicular width wc of the light receiving surface 102a, and the focal length of the imaging lens 4 is f, the angle value α satisfies the following equation;
α = arctan (wc / 2f) / 2
The tilt angle of the rear stage mirror 6b is set so as to satisfy the above. An inner diameter w of the field stop 9 and a width wc of the light receiving surface 102a are expressed by the following formula:
m × w = wc / 2
If the angle value α is set to satisfy the following condition:
α = arctan (m × w / 2) / 2
Is set.

  Note that the light beam reflected by the rear stage mirror 6b with respect to the angle value α of the rear stage mirror 6b is reflected again by the rear stage dichroic mirror 5b with an angle of 2 × α and guided to the imaging lens 4, but the light beam is imaged. It is preferable to arrange the rear stage mirror 6b and the rear stage dichroic mirror 5b so as to pass through substantially the center of the pupil of the lens 4. At this time, the rear stage mirror 6b and the rear stage dichroic mirror 5b are disposed in consideration of parameters such as the distance from the pupil of the imaging lens 4 and the distance between the rear stage mirror 6b and the rear stage dichroic mirror 5b.

According to the light splitting optical device 1 described above, the observation light formed by the microscope device can be output simultaneously as two light images that are spectrally separated by the wavelength, and two-wavelength images of the sample can be observed simultaneously. it can. At this time, the position of the image forming lens 4 is configured so as to be movable in a direction intersecting the optical axis L ₁ of the collimator lens 3, the dichroic mirror 5a, 5b are detachably composed on the optical axis L ₁ . Thereby, when switching between the double view mode and the single view mode, the position of the imaging lens 4 is changed and the dichroic mirrors 5a and 5b are attached and detached to adjust the imaging position of the optical image on the light receiving surface 102a. Can do. Specifically, one light image is formed at the center of the light receiving surface 102a when used in the single view mode, and two light images are separately formed on the light receiving surface 102a when used in the double view mode. be able to. As a result, setting work at the time of switching the observation mode is facilitated, and the balance of the entire apparatus before and after switching of the observation mode can be stabilized. That is, when attaching the light splitting optical device 1 together with the camera device 101 to the microscope device, the cylindrical portions 2a and 2b of the housing 2 and the axis of the camera device 101 are arranged coaxially regardless of the observation mode. The position of the camera device 101 is easily stabilized without tilting. Further, since it is not necessary to adjust the position of the relatively heavy camera device 101 at the time of switching the observation mode, the operation at the time of switching the mode is easy.

  Here, since the shift amount A of the imaging lens 4 in the second state is set to m × w / 2 or more, the two light images formed on the light receiving surface 102a overlap on the light receiving surface 102a. Can be reliably prevented. Further, when the shift amount A of the imaging lens 4 is set equal to m × w / 2, the two light images formed on the light receiving surface 102a are arranged close to each other on the light receiving surface 102a. Therefore, two light images of the sample can be efficiently observed by effectively using the light receiving surface 102a. At this time, by setting the inner diameter w of the field stop 9 so as to be equal to wc / (2 × m), the imaging range of the two optical images is arranged in two divided on the entire light receiving surface 102a. Therefore, the sample image can be observed more efficiently by effectively utilizing the light receiving surface 102a.

  Further, the field stop 9 is configured so that its inner diameter can be variably set. Therefore, when the observation is performed by switching between the double view mode and the single view mode, the light receiving surface 102a is effectively used for efficient observation. can do. Specifically, by reducing the inner diameter of the field stop 9 in the double view mode and increasing the inner diameter of the field stop 9 in the single view mode, a wider range of the light receiving surface 102a can be used for observation.

  Further, since the two dichroic mirrors 5a and 5b are made of optical members having the same optical characteristics, the manufacturing cost can be reduced.

  In addition, this invention is not limited to embodiment mentioned above.

FIG. 4 is a perspective view showing an internal configuration of a light splitting optical device 1A according to a modification of the present invention, and FIG. In the light dividing optical device 1A, in place of being set by shifting α degree inclination angle from a plane orthogonal to the optical axis L ₁ of the subsequent mirror 6b from 45 °, orthogonal to the optical axis L ₁ of the subsequent dichroic mirror 5b The inclination angle from the surface is shifted from 45 degrees and set to 45-α degrees. Even with such a structure, the second split light B ₃ can enter the imaging lens 4 along a direction oblique to the optical axis L ₁ . As a result, the second split light B _{3 that} has passed through the imaging lens 4 shifts from the center on the light receiving surface 102a of the camera device 101 in accordance with the inclination angle and position of the rear-stage dichroic mirror 5b. The image is formed at a position shifted in the direction opposite to the direction (for example, the position of the upper half of the light receiving surface 102a shown in FIG. 5). Accordingly, the first and second light images formed by the first and second divided lights can be separated and arranged on the light receiving surface 102a.

6 is a perspective view showing an internal configuration of a light splitting optical device 1B according to another modification of the present invention, and FIG. 7 shows a spectral state of two light images in the light splitting optical device 1B of FIG. FIG. In the light dividing optical device 1A, the angular displacement direction of light division optical system 45 degrees of tilt angle 1 with respect to a plane orthogonal to the optical axis L ₁ of the subsequent mirror 6b is set in the reverse direction, its inclination angle 45- Set to α degrees. Further, the light splitting optical device 1A, the image forming lens 4, the imaging lens moving mechanism 8B, the optical axis L ₂ is shifted in the reverse direction by a predetermined distance A from the optical axis L ₁ and the light splitting optical device 1 2 can be set. According to such a structure, the first split light B _{2 that} has passed through the imaging lens 4 corresponds to the shift amount A and the shift direction of the imaging lens 4 and is centered on the light receiving surface 102 a of the camera device 101. The image is formed at a position shifted from the position (for example, the upper half position of the light receiving surface 102a shown in FIG. 7). At the same time, the second split light B ₃ passes through the mirrors 6 a and 6 b and is then reflected by the dichroic mirror 5 b and input to the imaging lens 4. At this time, the inclination angle with respect to a plane orthogonal to the optical axis L ₁ of the subsequent mirror 6b is set to 45-alpha degree, the position of the subsequent dichroic mirror 5b is deviated from the optical axis L ₁ in the same direction as the imaging lens 4 Thus, the second split light B ₃ is incident on the imaging lens 4 along a direction oblique to the optical axis L ₁ . Imaging result, the second split light B ₃ passed through the imaging lens 4, corresponding to the position of the tilt angle and subsequent dichroic mirror 5b of the subsequent mirror 6b, from the center on the light receiving surface 102a of the camera device 101 The image is formed at a position shifted in a direction opposite to the direction in which the lens 4 is shifted (for example, the position of the lower half of the light receiving surface 102a shown in FIG. 7). Accordingly, the first and second light images formed by the first and second divided lights can be separated and arranged on the light receiving surface 102a.

8 is a perspective view showing an internal configuration of a light splitting optical device 1C according to another modification of the present invention, and FIG. 9 shows a spectral state of two light images in the light splitting optical device 1C of FIG. FIG. In the light division optical system 1C, are omitted the subsequent dichroic mirror 5b and the rear stage mirror 6b, the correction lens 7 is disposed on the optical axis L ₁ between the front dichroic mirror 5a and the imaging lens 4. In the optical splitting optical device 1C, the inclination angle with respect to a plane orthogonal to the optical axis L ₁ of the preceding stage mirror 6a is set to 45 + alpha degrees. Here, the deviation angle from 45 degrees of the inclination angle of the front mirror 6a alpha, displacement amount A of the optical axis L ₂ of the image forming lens 4 in the second state is set under the same conditions as the light dividing optical device 1 The Even with such a structure, the first split light B ₂ transmitted through the dichroic mirror 5 a is shifted from the center on the light receiving surface 102 a of the camera device 101 in accordance with the shift amount A and the shift direction of the imaging lens 4. The image is formed at a certain position (for example, the lower half position of the light receiving surface 102a shown in FIG. 9). At the same time, the second split light B ₃ reflected by the dichroic mirror 5a and the mirror 6a is incident on the imaging lens 4 along an oblique direction with respect to the optical axis L _1. As a result, the inclination angle of the mirror 6a is increased. Correspondingly, an image is formed at a position shifted from the center on the light receiving surface 102a of the camera device 101 in the direction opposite to the direction of the image forming lens 4 (for example, the upper half position of the light receiving surface 102a shown in FIG. 9). The Accordingly, the first and second light images formed by the first and second divided lights can be separated and arranged on the light receiving surface 102a.

DESCRIPTION OF SYMBOLS 1,1A, 1B, 1C ... Light splitting optical device, 3 ... Collimator lens, 4 ... Imaging lens, 5a ... Pre-stage dichroic mirror (beam splitter), 5b ... Post-stage dichroic mirror (second beam splitter), 6a ... Pre-stage Mirror (reflective optical element), 6b ... latter stage mirror (second reflective optical element), 7 ... correction lens, 8, 8B ... imaging lens moving mechanism, 9 ... field stop, 101 ... camera device, 102 ... imaging device, 102a... Light receiving surface, L ₁ , L ₂ .

Claims (10)

A field stop for limiting the field of view on the imaging plane of the external observation light; and
A collimator lens that receives observation light that has passed through the field stop, converts the observation light into parallel light, and outputs the parallel light;
A beam splitter disposed on the optical axis of the collimator lens to transmit the parallel light and output it as first split light, and to reflect the parallel light and output as second split light;
A reflective optical element that reflects the second split light output from the beam splitter;
A first optical image is output by imaging the first split light output from the beam splitter and disposed on the optical axis of the collimator lens, and the reflective optical element is output from the beam splitter. An imaging lens that outputs a second optical image by imaging the second split light output via
An imaging lens moving mechanism for moving the imaging lens relative to the collimator lens in a direction intersecting the optical axis of the collimator lens ;
A light splitting device. The imaging lens moving mechanism is
When the imaging magnification by the collimator lens and the imaging lens is m and the width of the field stop in the direction perpendicular to the optical axis of the collimator lens is w, the optical axis of the imaging lens is the collimator lens. Configured to move so as to deviate by more than m × w / 2 from the optical axis of
The light splitting device according to claim 1. The imaging lens moving mechanism is
The optical axis of the imaging lens is configured to move so as to deviate by about m × w / 2 from the optical axis of the collimator lens.
The light splitting device according to claim 2. The field stop is configured to be able to variably set the width in the direction perpendicular to the optical axis of the collimator lens.
The light splitting device according to claim 1. The beam splitter is constituted by a dichroic mirror,
The light splitting device according to claim 1. An imaging device having a light receiving surface at the imaging position of the first and second optical images output from the imaging lens;
When the imaging magnification by the collimator lens and the imaging lens is m and the width of the light receiving surface in the direction perpendicular to the optical axis of the collimator lens is wc, the optical axis of the collimator lens of the field stop is The width w in the vertical direction is set to wc / (2 × m).
The light splitting device according to any one of claims 1 to 5. The beam splitter is configured to be removable from the optical axis of the collimator lens,
The imaging lens moving mechanism includes a first state in which the optical axis of the imaging lens and the optical axis of the collimator lens coincide with each other, and the optical axis of the imaging lens is that of the collimator lens. The imaging lens is configured to be movable so as to be in any one of the second state shifted from the optical axis.
The light splitting device according to any one of claims 1 to 6. The reflective optical element causes the second split light to enter the imaging lens along a direction oblique to the optical axis of the imaging lens;
The light splitting device according to claim 1. A second reflective optical element that further reflects the second split light via the reflective optical element;
The second split light, which is disposed on the optical axis of the collimator lens, transmits the first split light output from the beam splitter and outputs the second split light via the second reflective optical element. A second beam splitter that reflects and outputs,
The imaging lens outputs a first optical image by imaging the first divided light output from the second beam splitter, and also outputs the first optical image from the second beam splitter. Outputting a second optical image by imaging the two split lights;
The light splitting device according to claim 1.   An imaging device having a light receiving surface at the imaging position of the first and second optical images output from the imaging lens;
  The imaging lens moving mechanism moves the imaging lens relative to the light receiving surface of the imaging element.
The light splitting device according to any one of claims 1 to 9.

Images