JP5880230B2 - Optical device - Google Patents

Description

  The present invention relates to an optical apparatus such as a camera, a video camera, a microscope, and a telescope.

  Conventionally, in an optical device such as an optical viewfinder, a microscope, and a telescope of a camera or a video camera, an imaging optical system for photographing and an afocal optical system for visual observation are provided independently, or an afocal optical system is connected. Various configurations have been proposed such as branching in the middle of the optical path of the image optical system (see, for example, Patent Document 1).

JP 2006-301514 A

  If the image forming optical system and the afocal optical system are provided separately as in the prior art, there is a problem that the apparatus becomes large.

  The present invention has been made in view of such problems, and is miniaturized by forming two optical paths having different functions in the same optical system by utilizing the refraction and reflection action of the constituent lens elements. It is an object of the present invention to provide an optical device that achieves the above.

In order to achieve such an object, according to a first aspect illustrating the present invention, an optical apparatus configured to include a transmission optical system including a plurality of lens elements, which is incident on the transmission optical system. A first reflecting surface that transmits a part of the light beam and reflects a part thereof; a second reflecting surface that transmits the incident light beam to the transmission optical system and reflects the reflected light reflected by the first reflecting surface to the emission side; An optical path that is incident on the transmissive optical system, is transmitted through the first and second reflective surfaces, and is emitted by the refracting action of the lens element constituting the transmissive optical system. An optical path that is incident on the transmission optical system, is reflected by the first reflecting surface, and is emitted after being reflected by the second reflecting surface, constitutes a second optical system, and Either one of the second optical systems forms an image An academic system, the other optical device which is a afocal optical system is provided.

  According to the present invention, it is possible to provide an optical device that is miniaturized by forming two optical paths having different functions in the same optical system by utilizing the refraction and reflection action of the constituent lens elements. .

It is a schematic block diagram of the optical apparatus which concerns on this embodiment. It is an optical path diagram when the optical device according to the present embodiment is provided with functions as (a) an imaging optical system and (b) an afocal optical system. FIG. 6 is an optical path diagram when the imaging position and the exit pupil position are changed in the case where the optical apparatus according to the present embodiment has functions as an imaging optical system and an afocal optical system, respectively. It is explanatory drawing at the time of forming a half mirror in the reflective surface of the optical apparatus which concerns on this embodiment. It is a figure which shows an example of the surface which has installed in order to isolate | separate an incident light beam into two light beams, and has a transmission area | region and a reflection area | region in the optical apparatus which concerns on this embodiment. It is a figure which shows an example of the surface which has installed in order to isolate | separate an incident light beam into two light beams, and has a transmission area | region and a reflection area | region in the optical apparatus which concerns on this embodiment. It is a figure which shows an example of the surface which has installed in order to isolate | separate an incident light beam into two light beams, and has a transmission area | region and a reflection area | region in the optical apparatus which concerns on this embodiment. In the first and second reflecting surfaces constituting the optical device according to the present embodiment, when (a) a half mirror is used, (b) a polarization state when a polarizing beam splitter (wire grid) and a half mirror are used FIG. 1 is a structural cross-sectional view of an optical device according to a first example. It is an optical path diagram in the case of making the optical apparatus which concerns on 1st Example function as an imaging optical system. It is an optical path figure in the case of making the optical apparatus which concerns on 1st Example function as an afocal optical system. It is a structure sectional view of the optical device concerning the 2nd example. It is an optical path diagram in the case of making the optical apparatus which concerns on 2nd Example function as an imaging optical system. It is an optical path figure in the case of making the optical apparatus which concerns on 2nd Example function as an afocal optical system. It is a structure sectional drawing of the optical apparatus which concerns on 3rd Example. It is an optical path diagram in the case of making the optical apparatus which concerns on 3rd Example function as an imaging optical system. It is an optical path figure in the case of making the optical apparatus which concerns on 3rd Example function as an afocal optical system.

  Hereinafter, embodiments will be described with reference to the drawings. As shown in FIG. 1, the optical device 1 according to the present embodiment is configured to include a transmission optical system OPS composed of a plurality of lens elements, and transmits a part of the incident light beam to the transmission optical system OPS and a part thereof. And a second reflection surface R2 that transmits the incident light flux to the transmission optical system OPS and reflects the reflected light reflected by the first reflection surface R1 to the exit side, and includes transmission optics. Due to the refractive action of the lens elements constituting the system OPS, the optical path 10 that enters the transmission optical system OPS, passes through the first reflection surface R1 and the second reflection surface R2, and exits, forms the first optical system, and is transmitted. The optical path 20 that enters the optical system OPS, is reflected by the first reflecting surface R1, and is emitted after being reflected by the second reflecting surface R2 constitutes the second optical system.

  As described above, the optical device 1 includes the two reflecting surfaces R1 and R2 in the transmissive optical system OPS, and uses the refracting action of the lens elements constituting the transmissive optical system OPS, thereby allowing the light beam to pass through all the optical surfaces. An optical path 10 that passes through and an optical path 20 that exits after the light beam has been reflected an even number of times are formed and have different functions (for example, the first and second optical systems have an imaging optical system and an afocal). A function as an optical system). That is, the optical device 1 can include two optical paths (optical systems) having different functions in the same optical system, and the size of the device can be reduced.

  In the optical apparatus 1 according to the present embodiment, two or more different functions are provided in the same optical system if a reflective surface is provided in the transmissive optical system OPS so as to cause an even number of reflections different from the above. It is also possible to provide an optical path (optical system) having

  In the optical device 1 according to this embodiment, the transmission optical system OPS is designed so that the aberration with respect to the incident light beam is good both in the optical path 10 (first optical system) and in the optical path 20 (second optical system). It is desirable that

  In the optical device 1 according to the present embodiment, one of the first optical system and the second optical system is an imaging optical system (see FIG. 2A), and the other is an afocal optical system ( It is preferable to refer to FIG. For example, as shown in FIG. 2A, if an image sensor S is installed at the imaging position of the imaging optical system, an object image can be captured. As shown in FIG. 2B, afocal optics is used. If the observer's eye E is placed at the exit pupil position of the system, the object image can be visually observed. That is, if the optical device 1 is used, it is possible to perform imaging and visual observation of an object image simply by switching the position of the imaging element S and the eye E of the observer.

  In FIG. 2, the imaging position of the imaging optical system shown in FIG. 2 (a) and the exit pupil position of the afocal optical system shown in FIG. 2 (b) are drawn to match, but these positions are not matched. It is also possible to design. For example, as shown in FIG. 3, the exit pupil position E ′ of the afocal optical system can be set behind the imaging position S ′ of the imaging optical system.

  In the present embodiment, when any one of the first and second optical systems is made to function as an afocal optical system, the image is designed to be an upright image or an inverted image during visual observation. It is possible. For example, when an inverted image is visible by visual observation, a prism such as a Porro prism can be placed inside the afocal optical system to make it an erect image.

  In FIG. 2, in the imaging optical system shown in FIG. 2 (a) and the afocal optical system shown in FIG. 2 (b), the incident angles of light rays from an object (not shown) are made to coincide with each other. Designs with different incident angles for each optical system are also possible.

  In FIG. 2, the incident light beam diameter is drawn with the same size in the imaging optical system shown in FIG. 2 (a) and the afocal optical system shown in FIG. 2 (b). Different designs are possible.

  In the optical device 1 according to the present embodiment, it is preferable that the first reflecting surface R1 and the second reflecting surface R2 are respectively provided on any lens surface of the lens element. With such a configuration, it is possible to give various functions to one optical system without increasing the number of components, and it is possible to contribute to downsizing of the apparatus. In the first example described later, the first reflecting surface R1 and the second reflecting surface R2 are the image side lens surface of the lens L9 (surface number 18 in Table 1) and the image side lens surface of the lens L7 (in Table 1). Surface number 14). In the second embodiment, the first reflecting surface R1 and the second reflecting surface R2 are the image side lens surface of the lens L5 (surface number 10 in Table 2) and the image side lens surface of the lens L3 (surface number 6 in Table 2). Is provided. In the third example, the first reflecting surface R1 and the second reflecting surface R2 are the image side lens surface of the lens L9 (surface number 18 in Table 3) and the image side lens surface of the lens L7 (surface number 14 in Table 3). Is provided.

  In the optical device 1 according to this embodiment, it is preferable that an antireflection film is provided on an optical surface other than the first reflecting surface R1 and the second reflecting surface R2. With this configuration, it is possible to prevent unnecessary reflection of the light flux in the optical system and to ensure good optical performance.

  In the optical device 1 according to the present embodiment, as shown in FIG. 4, it is preferable that a half mirror is formed on at least one of the first reflecting surface R1 and the second reflecting surface R2. With this configuration, it is possible not only to separate the incident light beam into two light beams, but also to adjust the light amount of the light beam emitted for each optical path according to the purpose of use.

In FIG. 4, a half mirror having a transmittance of 50% and a reflectance of 50% is employed for each of the first reflecting surface R1 and the second reflecting surface R2, and the light amount ratio is approximately optical path 10: optical path 20 = 4: 1. The case where it becomes is illustrated. In the optical path 10, when the incident light beam passes through the first reflecting surface R 1 and the second reflecting surface R 2, it passes through the half mirror a total of two times. Become ² . In the optical path 20, when the incident light beam is transmitted through the second reflecting surface R 2, reflected by the first reflecting surface R 1 and the second reflecting surface R 2, and then transmitted through the first reflecting surface R 1, the total number of half mirrors is 4. Therefore, the amount of the emitted light is about (0.5) ⁴ with respect to the incident light.

  The optical system shown in FIG. 4 with the light amount adjusted in this way can be used as a camera and a telescope, for example. Since recent cameras have good sensitivity, the amount of light on the camera can be reduced relative to the telescope. In the optical system shown in FIG. 4, since the light quantity ratio is approximately optical path 10: optical path 20 = 4: 1, the optical path 10 is used as a focal optical system for a telescope, and the optical path 20 is used as an imaging optical system for a camera. It is preferable to use it.

  The adjustment of the amount of emitted light for each optical path can be appropriately set by employing a half mirror having different characteristics (for example, a half mirror having a transmittance of 30% and a reflectance of 70%) according to the purpose of use. Is possible.

  In the optical device 1 according to this embodiment, the same effect can be obtained by forming a polarizing film on at least one of the first reflecting surface R1 and the second reflecting surface R2 instead of the above-described half mirror.

  In the optical device 1 according to the present embodiment, it is preferable that the first reflecting surface R1 and the second reflecting surface R2 are substantially flat. With this configuration, it is easy to install a half mirror or a polarizing film on the first reflecting surface R1 and the second reflecting surface R2.

  In the optical device 1 according to the present embodiment, the first reflecting surface R1 and the second reflecting surface R2 are formed in a transmissive region (in the drawing, a dark color in accordance with the purpose of use), as shown in FIGS. It is also possible to design it by dividing it into a hatched part) and a reflection area so that the incident light beam passing through this surface is separated into two optical paths.

  In the optical device 1 according to this embodiment, the position of the entrance pupil of the transmission optical system OPS can be designed in front, center, and rear of the optical system according to the purpose. In particular, when the entrance pupil position is set to the front, the combination with other optical devices is facilitated.

  In the optical device 1 according to the present embodiment, a polarizing element can be used when the incident light beam is separated into two optical paths. For example, if only a half mirror is used in an optical system (without using a polarizing element), two separated light beams overlap each other, so that it can often be used sufficiently, but in some cases, it is visible to the observer. There are things that are not good. In the latter case, it is possible to improve the appearance by using polarized light by incorporating a polarizing element according to the purpose of use (for example, balancing the degree of polarization and transmittance) in the optical system. In addition, it is possible to adjust the amount of light emitted from each optical path.

  In FIG. 8A, the incident light beam is separated into two (that is, the optical path 10a and the optical path 20a), the polarization directions are different by 90 degrees in each of the optical paths 10a and 20a, and the light quantity ratio is approximately 4: 1. The usage example of the polarizing element comprised in 1 is shown. Specifically, the polarizing element includes a first polarizing plate 31 provided on the most object side, and a first quarter-wave plate provided between the first polarizing plate 31 and the second reflecting surface R2. 32, a second quarter-wave plate 33 provided between the second reflecting surface R2 and the first reflecting surface R1, and a second polarizing plate 34 provided behind the first reflecting surface R1. Configured. And the 1st polarizing plate 31 and the 2nd polarizing plate 34 are arrange | positioned so that a mutual direction may be parallel or orthogonal. The first and second reflecting surfaces R1 and R2 are provided with half mirrors having a transmittance of 50% and a reflectance of 50%, respectively.

  The incident light beam passes through the first polarizing plate 31, the first quarter-wave plate 32, the second reflecting surface R2, the second quarter-wave plate 33, the first reflecting surface R1, and the second polarizing plate 34. The light path 10a that is transmitted and emitted in sequence, the first polarizing plate 31, the first quarter-wave plate 32, the second reflection surface R2, and the second quarter-wave plate 33 are transmitted through the first reflection surface. Reflected by R1, reflected by the second reflecting surface R2 through the second quarter-wave plate 33, and again through the second quarter-wave plate 33, the first reflecting surface R1 and the second polarizing plate 34. Are separated into two different light fluxes from the optical path 20a that exits after passing through.

  Here, the behavior of the light flux in each optical path will be described. In the optical path 10a, the incident light flux, which is non-polarized light, passes through the first polarizing plate 31 and becomes linearly polarized light in the direction orthogonal to the plane of the drawing. After being transmitted through the wave plate 32 and converted into circularly polarized light, and after passing through the second quarter wave plate 33 through the half mirror (second reflecting surface) R2, it is converted into linearly polarized light in the direction parallel to the paper surface. The light passes through the half mirror (first reflecting surface) R 1 and enters the second polarizing plate 34. If the polarization direction at this time is parallel to the second polarizing plate 34, it is transmitted, and if it is orthogonal to the second polarizing plate 34, it is blocked here.

  In the optical path 20a, the incident light beam which is non-polarized light is transmitted through the first polarizing plate 31 to become linearly polarized light in the direction orthogonal to the plane of the drawing, is transmitted through the first quarter wavelength plate 32 and is converted into circularly polarized light, and half-polarized light. The light is transmitted through the second quarter-wave plate 33 through the mirror (second reflection surface) R2 and converted into linearly polarized light in the direction parallel to the paper surface, and is reflected by the half mirror (first reflection surface) R1 and the second 1 / 4 wavelength plate 33 is transmitted to be converted into circularly polarized light, reflected by half mirror (second reflection surface) R2, transmitted through second quarter wavelength plate 33, and converted to linearly polarized light in the direction perpendicular to the paper surface. Later, the light passes through the half mirror (first reflection surface) R 1 and enters the second polarizing plate 34. If the polarization direction at this time is parallel to the second polarizing plate 34, it is transmitted, and if it is orthogonal to the second polarizing plate 34, it is blocked here.

If the polarizing element shown in FIG. 8A is used, the incident light beam can be separated into two light beams whose polarization directions are different by 90 degrees. Further, the light amount at the time of injection for each optical path, compared with the time of the incident, about an optical path 10a (0.5) ^3, and becomes about (0.5) ⁵ in the optical path 20a. That is, the light quantity ratio is approximately optical path 10a: optical path 20a = 4: 1.

  In this way, by using the polarizing element shown in FIG. 8A, the incident light beam can be separated into two light beams, and the polarization state can be set according to the purpose of use for each optical path to adjust the light amount. Is possible.

  If a device using this polarizing element is used as a camera and a telescope, using the good sensitivity of recent cameras, the light path with the least amount of light is assigned to the camera, and the light path with the greater amount of light is used as the telescope. Can be assigned. In the apparatus of FIG. 8A, since the light quantity ratio is approximately optical path 10a: optical path 20a = 4: 1, the optical path 10 is used for a telescope as an afocal optical system, and the optical path 20 is used as an imaging optical system for a camera. It is possible to use it. Rather than providing two optical systems and providing two functions (camera, telescope) from the viewpoint of downsizing the apparatus, a polarizing element is incorporated into one optical system as described above. We think that it is more advantageous to have a function.

  In this embodiment, instead of the first reflecting surface R1 and the second polarizing plate 34 in FIG. 8A, it is also possible to arrange a polarizing beam splitter 35 having both functions (FIG. 8). (See (b)).

In FIG. 8B, the polarizing element includes a first polarizing plate 31 provided on the most object side, and a first quarter wavelength provided between the first polarizing plate 31 and the second reflecting surface R2. The plate 32, the second reflecting surface R2, and the first
A configuration having a second quarter-wave plate 33 provided between the reflecting surface R1 and a polarizing beam splitter 35 provided behind the second quarter-wave plate 33 (in place of the first reflecting surface R1 and the second polarizing plate 34). I have to. The first polarizing plate 31 and the polarizing beam splitter 35 are arranged so that their directions are parallel or orthogonal to each other. In addition, a half mirror is provided on the second reflecting surface R2.

  The incident light beam passes through the first polarizing plate 31, the first quarter-wave plate 32, the second reflecting surface R2, the second quarter-wave plate 33, and the polarizing beam splitter 35 (first reflecting surface R1). The light passes through the optical path 10b that is sequentially transmitted and exits, the first polarizing plate 31, the first quarter-wave plate 32, the second reflecting surface R2, and the second quarter-wave plate 33, and the polarizing beam splitter 35. Reflected by (first reflecting surface R1), reflected by second reflecting surface R2 through second quarter-wave plate 33, and polarized beam splitter 35 (first reflecting plate by way of second quarter-wave plate 33). The light is separated into two different light beams from the optical path 20b that exits after passing through the surface R1).

  The behavior of the light flux in each optical path will be described. In the optical path 10b, the incident light flux which is non-polarized light passes through the first polarizing plate 31 and becomes linearly polarized light in the direction orthogonal to the paper surface, and the first quarter-wave plate 32. Is then converted into circularly polarized light, transmitted through the second quarter-wave plate 33 through the half mirror (second reflecting surface) R2, and converted into linearly polarized light in the direction parallel to the paper surface, and then the polarization beam splitter. 35 (first reflecting surface R1). If the polarization direction at this time is parallel to the polarization beam splitter 35, it is transmitted, and if it is orthogonal to the polarization beam splitter 35, it is blocked here.

  In the optical path 20b, the incident light beam, which is non-polarized light, passes through the first polarizing plate 31 and becomes linearly polarized light in the direction orthogonal to the plane of the paper, passes through the first quarter-wave plate 32, and is converted into circularly polarized light. The light is transmitted through the second quarter-wave plate 33 through the mirror (second reflection surface) R2, converted into linearly polarized light in the direction parallel to the paper surface, reflected by the polarization beam splitter 35 (first reflection surface R1), and second. Is transmitted through the quarter-wave plate 33 and converted into circularly polarized light, reflected by the half mirror (second reflecting surface) R2 and transmitted through the second quarter-wave plate 33 and converted into linearly polarized light in the direction orthogonal to the paper surface. Then, the light enters the polarizing beam splitter 35 (first reflection surface R1). If the polarization direction at this time is parallel to the polarization beam splitter 35, it is transmitted, and if it is orthogonal to the polarization beam splitter 35, it is blocked here.

If the polarizing element shown in FIG. 8B is used, the incident light beam can be separated into two light beams whose polarization directions are different by 90 degrees. Further, if the polarizing beam splitter 35 and the half mirror provided on the first reflecting surface R1 and the second reflecting surface R2 have performances according to the purpose of use, the light amount can be adjusted for each optical path. For example, when it is desired that the light quantity ratio for each optical path is approximately optical path 10b: optical path 20b = 2: 1, the polarizing beam splitter 35 and the half mirror have transmittance of 50% and reflectance of 50%, respectively. Adopt it. Amount of time of injection as compared with the time of incidence, about an optical path 10b (0.5) ^2, and becomes an optical path 20b about (0.5) ^3. That is, the light quantity ratio is approximately optical path 10b: optical path 20b = 2: 1.

  In this way, by using the polarizing element shown in FIG. 8B, the incident light beam can be separated into two light beams, and the polarization state can be set according to the purpose of use for each optical path to adjust the light amount. Is possible.

  The polarizing beam splitter 35 is preferably a wire grid type polarization separating element. This configuration can contribute to downsizing of the device.

Hereinafter, examples of the optical device according to the present embodiment will be described with reference to the drawings. Tables 1 to 3 are shown below, but these are tables of specifications of each lens in the first to third examples.

  In [Overall specifications] in the table, f represents the focal length (mm) at the d-line of the optical system, φ represents the entrance pupil diameter (mm), and FNo represents the F number.

  In [Lens data] in the table, the surface number indicates the order of the optical surfaces from the object side along the direction in which the light beam travels, R indicates the radius of curvature of each optical surface, and d indicates the next optical surface from each optical surface. The distance between the surfaces, which is the distance on the optical axis to (or the image plane), nd is the refractive index with respect to the d-line (wavelength 587.562 nm) of the glass material used for the lens, and νd is the d-line of the glass material used for the lens. Indicates the Abbe number. In the table, the description of the refractive index of air (d-line) “1.000000” is omitted.

  The units of the focal length f, the radius of curvature R, the surface interval d, and other lengths in the table are “mm”. However, since the optical system can obtain the same optical performance even if it is proportionally enlarged or reduced, the unit is not limited to “mm”, and other appropriate units can be used.

(First embodiment)
The optical device according to the first example will be described with reference to FIGS. 9 to 11 and Table 1. FIG. In the optical device 100 according to the first example, the transmission optical system OPS1 is configured so that the incident light beam is transmitted through all the lens elements when functioning as the imaging optical system. In the case of functioning as an afocal optical system, the incident light beam has a lens surface indicated by surface number 18 and a lens surface indicated by surface number 14 in Table 1 (corresponding to the first and second reflecting surfaces of claim 1) ) Are reflected twice and then emitted (corresponding to the second optical system of claim 1).

  As shown in FIG. 9, the optical device 100 according to the first example includes a transmission optical system OPS1 including eleven lenses L1 to L11 arranged in order from the object side along the optical axis, and an imaging element S1. Composed.

  The imaging element S1 is provided so that the imaging surface is positioned at the imaging position of the transmission optical system OPS1 including the lenses L1 to L11. Moreover, it is provided so that it can be inserted and removed from the optical path.

  Table 1 below shows lens data according to this example. Surface numbers 1 to 22 in Table 1 correspond to the optical surfaces having the curvature radii R1 to R22 shown in FIG.

  In this embodiment, a diaphragm (not shown) for adjusting the brightness is provided at the position of surface number 13 in [Lens data] in Table 1.

(Table 1)
[Overall specifications]
f = 50
φ = 10
Fno = 5

[Lens data]
Surface number R d nd νd
1 157.333 6.0 1.717000 47.98
2 -111.795 18.0
3 22.697 6.0 2.000690 25.46
4 344.012 2.0
5 -43.839 6.0 1.755200 27.57
6 6.817 8.1
7 -10.852 3.9 1.720000 43.61
8 -9.078 6.0
9 19.486 2.0 1.638540 55.34
10 -19.122 0.1
11 -25.848 2.0 2.000690 25.46
12 18.358 6.8
13 48.511 6.0 1.640000 60.2
14 -322.708 15.0
15 -290.377 6.0 2.000690 25.46
16 -77.946 20.0
17 77.519 6.0 1.697000 48.45
18 291.524 5.0
19 -15.000 6.0 1.539960 59.52
20 -19.025 3.9
21 36.168 5.0 1.456000 91.36
22 -48.925 29.7

  The optical device 100 according to the first embodiment is designed so that a light beam from an infinite distance with a half field angle of 6.16 degrees is incident with an entrance pupil diameter of 10 mm. In addition, the optical device 100 according to the present embodiment is designed so that the aberration performance is good for each wavelength of C-line, d-line, F-line, and g-line. That is, the aberration performance is good for light having wavelengths in the entire visible range.

  In the optical apparatus 100 according to the first example having the above-described configuration, as shown in FIG. 10, the light beam that has entered the apparatus from infinity is sequentially transmitted through the lenses L1 to L11 constituting the transmission optical system OPS1, and the lens L11. To 29.7 mm behind. That is, the transmission optical system OPS1 behaves as an imaging optical system. If the image pickup device S1 is arranged so that the image pickup surface is located at the above-described image formation position, an image can be taken. That is, the optical device 100 according to the first example can be used as a camera, a video camera, or the like by using a function as an imaging optical system.

  In the optical apparatus 100 according to the first example, a light beam incident at a half field angle of 6.16 degrees forms an image at a position with an image height of about 5.3 mm. It is preferable to use a CMOS sensor.

  Further, in the optical device 100 according to the first example, as shown in FIG. 11, a light beam entering the device from infinity enters the lens L9 via the lenses L1 to L8, and the back surface ( Reflected once at surface number 18 in Table 1 (goes to the left in the drawing), goes to lens L7 via lens L8, and reflects again on the surface of this lens L7 (surface number 14 in Table 1). Proceeding to the right), the light passes through the lenses L8 to L11 in order, and is emitted as a parallel light beam. That is, the transmission optical system OPS1 behaves as an afocal optical system. Since the parallel light beam emitted from the transmission optical system OPS1 has good aberrations, the optical device 100 according to the first example (removed when the imaging element S1 is on the optical path) is rearward (from the drawing surface) from the lens L11. When the observer's eye E1 is placed at a position of 29.7 mm (right direction), the incident light beam from infinity is imaged on the retina of the observer's eye E1, and the observer can visually observe the infinity. .

In the optical device 100 according to the first embodiment, if a polarizing film or a half mirror having a transmittance / reflectance set according to the purpose of use is provided on the surface number 14 and the surface number 18 in Table 1, the optical path It is possible to adjust the light quantity of each emitted light beam. Further, it is desirable to apply an antireflection film to other optical surfaces (other than surface number 14 and surface number 18 in Table 1) so that unnecessary reflection of light flux does not occur. It is also possible to incorporate a polarizing element as shown in FIGS. 8A and 8B in the optical system of this embodiment and change the polarization state and the amount of emitted light for each optical path according to the purpose of use. .

(Second embodiment)
The optical device according to the second example will be described with reference to FIGS. In the optical device 200 according to the second example, the transmission optical system OPS2 is configured so that the incident light beam is transmitted through all the lens elements when functioning as an imaging optical system. In the case of functioning as an afocal optical system, the incident light flux corresponds to the lens surface indicated by surface number 10 and the lens surface indicated by surface number 6 in Table 2 (corresponding to the first and second reflecting surfaces of claim 1). ) Are reflected twice and then emitted (corresponding to the second optical system of claim 1).

  As shown in FIG. 12, the optical device 200 according to the second example includes a transmission optical system OPS2 composed of seven lenses L1 to L7 arranged in order from the object side along the optical axis, and an image sensor S2. Composed.

  The imaging element S2 is provided so that the imaging surface is positioned at the imaging position of the transmission optical system OPS2 including the lenses L1 to L7. Moreover, it is provided so that it can be inserted and removed from the optical path.

  Table 2 below shows lens data according to this example. Surface numbers 1 to 14 in Table 2 correspond to the optical surfaces having the curvature radii R1 to R14 shown in FIG.

  In this embodiment, a diaphragm (not shown) for adjusting the brightness is provided at the position of surface number 1 of [Lens data] in Table 2. With this configuration, the entrance pupil is projected to the front side (left direction in the drawing) of the transmission optical system OPS2 including the lenses L1 to L7, and the optical device 200 according to the second embodiment is easily combined with other optical systems. Can do.

(Table 2)
[Overall specifications]
f = 50
φ = 10
Fno = 5

[Lens data]
Surface number R d nd νd
1 54.929 2.7 2.000690 25.46
2 60.708 18.9
3 51.025 4.4 2.000690 25.46
4 -30.715 2.7
5 -21.064 2.6 2.000690 25.46
6 143.353 15.0
7 -26.674 7.0 2.000690 25.46
8 -251.911 5.0
9 -261.555 6.0 2.000690 25.46
10 -62.905 6.0
11 -149.239 8.0 2.000690 25.46
12 -52.730 0.1
13 52.560 6.0 2.000690 25.46
14 234.070 37.9

  The optical device 200 according to the second embodiment is designed so that an entrance pupil diameter is 10 mm and a light beam from infinity with a half field angle of 10 degrees is incident. In addition, the optical device 200 according to the present example is designed so that the aberration performance is good with respect to a wavelength of 632.8 nm (He-Ne laser).

  In the optical apparatus 100 according to the second example having the above-described configuration, as shown in FIG. 13, the light beam that has entered the apparatus from infinity is sequentially transmitted through the lenses L1 to L7 constituting the transmission optical system OPS2, and the lens L7. The image is formed at a position 37.9 mm behind. That is, the transmission optical system OPS2 behaves as an imaging optical system. If the image pickup device S2 is arranged so that the image pickup surface is at the above-described image formation position, an image can be taken. That is, the optical device 200 according to the second embodiment can be used as an optical element of a laser optical system by using a function as an imaging optical system.

  In the optical device 200 according to the second example, a light beam incident at a half angle of view of 10 degrees forms an image at a position with an image height of about 8.7 mm. Therefore, for example, a CCD sensor is used as the image sensor S2. preferable.

  Further, in the optical device 200 according to the second embodiment, as shown in FIG. 14, a light beam that has entered the device from infinity enters the lens L5 via the lenses L1 to L4, and the back surface of the lens L5 ( After reflecting once at surface number 10 in Table 2 (going to the left in the drawing), going to lens L3 via lens L4, and reflected again on the surface of this lens L3 (surface number 6 in Table 2), Proceeding to the right), the light passes through the lenses L4 to L7 in order, and is emitted as a parallel light beam. That is, the transmission optical system OPS2 behaves as an afocal optical system. Since the parallel light beam emitted from the transmission optical system OPS2 has good aberrations, the optical device 200 according to the second embodiment (extracted when the image pickup device S2 is on the optical path) is rearward (from the drawing surface) from the lens L7. If the observer's eye E2 is placed at a position of 37.9 mm (right direction), the incident light beam from infinity is imaged on the retina of the observer's eye E2, and the observer can visually observe the infinity. .

  The optical device 200 according to the second embodiment can be obtained by providing a polarizing film, a half mirror, or the like having a transmittance / reflectance according to the intended use on the surface number 6 and the surface number 10 in Table 2. It is possible to adjust the light quantity of each emitted light beam. Further, it is desirable to apply an antireflection film to other optical surfaces (other than surface number 6 and surface number 10 in Table 2) so that unnecessary reflection of light flux does not occur. It is also possible to incorporate a polarizing element as shown in FIGS. 8A and 8B in the optical system of this embodiment and change the polarization state and the amount of emitted light for each optical path according to the purpose of use. .

(Third embodiment)
The optical apparatus according to the third example will be described with reference to FIGS. 15 to 17 and Table 3. FIG. In the optical device 300 according to the third example, when the transmission optical system OPS3 is caused to function as an imaging optical system, the incident light flux is a lens surface indicated by surface number 18 in Table 3 and a lens surface indicated by surface number 14 (claimed). In the case where the light is emitted after being reflected twice in total (corresponding to the first and second reflecting surfaces in item 1) (corresponding to the second optical system in claim 1) and functioning as an afocal optical system. The incident light beam is configured to pass through all the lens elements (corresponding to the first optical system of claim 1).

  As shown in FIG. 15, the optical device 300 according to the third example includes a transmission optical system OPS3 including eleven lenses L1 to L11 arranged in order from the object side along the optical axis, and an image sensor S3. Composed.

  The imaging element S3 is provided so that the imaging surface is positioned at the imaging position of the transmission optical system OPS3 including the lenses L1 to L11. Moreover, it is provided so that it can be inserted and removed from the optical path.

  Table 3 below shows lens data according to this example. Surface numbers 1 to 22 in Table 3 correspond to the optical surfaces having the curvature radii R1 to R22 shown in FIG.

  In this embodiment, a diaphragm (not shown) for adjusting the brightness is provided at the position of surface number 15 of [Lens data] in Table 3. Further, in this embodiment, when the optical device 300 is caused to function as an imaging optical system, the surface of surface number 18 in Table 3 used as a reflecting surface is designed as a flat surface (infinite curvature). This configuration facilitates the installation of a polarizing film and a half mirror.

(Table 3)
[Overall specifications]
(When used as an imaging optical system)
f = 28
φ = 4
Fno = 7
(When used as an afocal optical system)
f = ∞
φ = 4.5

[Lens data]
Surface number R d nd νd
1 62.088 12.5 1.487703 70.31
2 -105.927 0.3
3 -116.573 5.0 1.795040 28.69
4 126.595 20.0
5 43.914 4.2 1.761820 26.58
6 75.547 20.0
7 27.610 2.0 1.487703 70.31
8 33.037 20.0
9 -86.892 4.2 1.487703 70.31
10 261.829 20.0
11 -69.518 3.0 1.698950 30.13
12 -10.303 0.2
13 -9.394 1.0 1.744000 44.81
14 30.944 5.0
15 12.108 3.0 1.603420 38.03
16 8.539 1.8
17 -31.820 1.0 1.456000 91.36
18 ∞ 0.2
19 13.188 2.0 1.497820 82.57
20 -21.609 0.2
21 11.400 1.2 2.000690 25.46
22 9.899 20.0

When the optical apparatus 300 according to the third embodiment having the above-described configuration is used as the imaging optical system shown in FIG. 16, the entrance pupil diameter is 4 mm, and the light beam from infinity up to a half field angle of 5 degrees is incident. Has been. When used as the afocal optical system shown in FIG. 17, the entrance pupil diameter is 4.5 mm.
And a light beam from infinity up to a half angle of view of 6 degrees is designed to be incident. In addition, the optical device 300 according to the present embodiment is designed so that aberration performance is good for each wavelength of the C-line, d-line, F-line, and g-line. That is, the aberration performance is good for light having wavelengths in the entire visible range.

  In the optical apparatus 300 according to the third example having the above-described configuration, as shown in FIG. 16, a light beam that has entered the apparatus from infinity enters the lens L9 via the lenses L1 to L8, and the lens L9 After being reflected once on the back surface (surface number 18 in Table 3) (proceeding to the left in the drawing), proceeding to lens L7 via lens L8, and reflected again on the surface of this lens L7 (surface number 14 in Table 3), (Proceeding to the right in the drawing) The lenses L8 to L11 are sequentially transmitted to form an image at a position 20.0 mm behind the lens L11. That is, the transmission optical system OPS3 behaves as an imaging optical system. If the image pickup device S3 is arranged so that the image pickup surface comes to the above-described image formation position, an image can be taken. That is, the optical device 300 according to the third example can be used as a camera, a video camera, or the like by using a function as an imaging optical system.

  In the optical device 300 according to the third example, a light beam incident at a half angle of view of 5 degrees forms an image at a position with an image height of about 2.4 mm. Therefore, for example, a CMOS sensor is used as the image sensor S3. preferable.

  Further, in the optical device 300 according to the third example, as shown in FIG. 17, the light beam entering the device from infinity is sequentially transmitted through the lenses L1 to L11 constituting the transmission optical system OPS3 to become a parallel light beam. And inject. That is, the transmission optical system OPS3 behaves as an afocal optical system. Since the parallel light beam emitted from the transmission optical system OPS3 has good aberration, the optical device 300 according to the third example (removed when the image pickup device S3 is on the optical path) is rearward from the lens L11 ( If the observer's eye E3 is placed at a position of 20.0 mm (to the right in the drawing), the incident light beam from infinity forms an image on the retina of the observer's eye E3, and the observer can observe the infinity visually. it can.

  The optical device 300 according to the third embodiment can be obtained by providing a polarizing film or a half mirror having a transmittance / reflectance according to the purpose of use on the surface number 14 and the surface number 18 in Table 3 as the optical path. It is possible to adjust the light quantity of each emitted light beam. Further, it is desirable to provide an antireflection film on other optical surfaces (other than surface number 14 and surface number 18 in Table 3) so that unnecessary reflection of light flux does not occur. It is also possible to incorporate a polarizing element as shown in FIGS. 8A and 8B in the optical system of this embodiment and change the polarization state and the amount of emitted light for each optical path according to the purpose of use. .

  According to the optical device according to the present embodiment having the above-described configuration, two optical paths having different functions (for example, one image is formed) using the refraction / reflection action of the constituent lens elements. By forming an optical system and the other is an afocal optical system, it is possible to reduce the size of the apparatus.

  So far, in order to make the present invention easy to understand, the configuration requirements of the embodiment have been described, but it goes without saying that the present invention is not limited to this.

OPS (OPS1, OPS2, OPS3) Transmission optical system R1 First reflection surface R2 Second reflection surface 10 Optical path (first optical system)
20 optical path (second optical system)
1 (100, 200, 300) Optical device S (S1, S2, S3) Image sensor E (E1, E2, E3) Observer eye Li lens (i = 1, 2, 3,...)

Claims (7)

An optical device configured to include a transmission optical system including a plurality of lens elements,
A first reflecting surface that transmits and reflects a part of the incident light beam to the transmission optical system; and a reflected light that is transmitted by the incident light beam to the transmission optical system and reflected by the first reflection surface. A second reflecting surface for reflecting on the exit side,
Due to the refractive action of the lens element constituting the transmissive optical system, an optical path that enters the transmissive optical system and passes through and exits the first and second reflecting surfaces constitutes the first optical system, and An optical path that enters the transmission optical system, is reflected by the first reflecting surface, and exits after being reflected by the second reflecting surface constitutes the second optical system ,
One of the first and second optical systems is an imaging optical system, and the other is an afocal optical system .   An optical device configured to include a transmission optical system including a plurality of lens elements,
  A first reflecting surface that transmits and reflects a part of the incident light beam to the transmission optical system; and a reflected light that is transmitted by the incident light beam to the transmission optical system and reflected by the first reflection surface. A second reflecting surface for reflecting on the exit side,
  Due to the refractive action of the lens element constituting the transmissive optical system, an optical path that enters the transmissive optical system and passes through and exits the first and second reflecting surfaces constitutes the first optical system, and An optical path that enters the transmission optical system, is reflected by the first reflecting surface, and exits after being reflected by the second reflecting surface constitutes the second optical system,
  A polarizing element is provided that changes the incident light beam to the transmission optical system so that the polarization states of the optical path constituting the first optical system and the optical path constituting the second optical system are different from each other. Optical device. The optical apparatus according to claim 2 , wherein one of the first and second optical systems is an imaging optical system, and the other is an afocal optical system. The optical device according to any one of claims 1 to 3, wherein the first and second reflecting surfaces are provided on any lens surface of the lens element, respectively. Wherein the first and optical surface other than the second reflecting surface, the optical device according to any one of claims 1 to 4, characterized in that the antireflection film is provided. Wherein at least one of the first and the second reflecting surface, the optical device according to any one of claims 1 to 5, characterized in that the half mirror is formed. It said first and said second reflecting surface, the optical device according to any one of claims 1 to 6, characterized in that a flat surface.

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