JP2008294317A - Imaging apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To simplify and downsize an imaging apparatus including a plurality of imaging optical systems. <P>SOLUTION: The imaging apparatus includes an object side telecentric lens optical system 30 which leads main ray of photographic subject light in parallel with an optical axis L, so that the subject light is divided into a plurality of optical paths and an image of a photographic subject is taken on each optical path, an optical path split component 40 which divides the outgoing light of object-side telecentric lens optical system into a plurality of optical paths, and a plurality of imaging lens optical systems 50 and 70 arranged on a plurality of optical paths divided by the optical path split components. Even when a photographic subject shifts from a predetermined imaging position or an image of peripheral region is to be taken, the object side telecentric lens optical system can take a highly accurate image which is not influenced by a movement of photographic subject or a imaging region. Also a plurality of imaging lens optical systems 50 and 70 sharing the single object side telecentric lens optical system 30 can reduce the number of parts, simplify the structure, reduce the size of equipment, and reduce cots, etc. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention is directed to imaging for recognizing the position, orientation, defects, and the like of an electronic component based on an image obtained by irradiating a subject (object) such as an electronic component sucked by a suction nozzle with light. More particularly, the present invention relates to an image pickup apparatus including a plurality of image pickup lens optical systems capable of picking up images of all or details of electronic components and the like.

In general, a surface mounter is known that transports and mounts electronic components such as semiconductor chips and resistors adsorbed by an adsorption nozzle onto a printed circuit board or the like. Such a surface mounter includes an image pickup device for picking up an image of an electronic component and detecting a positional deviation or an inclination of a posture at the time of suction generated between the suction nozzle and the electronic component.
Conventionally, as this type of imaging apparatus, a transparent dustproof glass that passes subject light (object light) from a subject such as an electronic component is disposed above and a casing that demarcates the optical path of the subject light is disposed inside the casing. A half mirror that transmits and reflects the subject light, a total reflection mirror that reflects the subject light that has passed through the half mirror, a small-field imaging camera that receives the subject light reflected by the half mirror and captures details. It is equipped with an imaging camera for a large field of view that receives the subject light reflected by the reflecting mirror and captures the entire image, and by switching between an imaging camera for a small field of view and an imaging camera for a large field of view, An apparatus that captures an entire image is known (for example, see Patent Document 1).

However, in such an imaging apparatus, since the imaging camera for the small field of view and the imaging camera for the large field of view each include a dedicated lens optical system, the object side telecentric lens that guides the principal ray of the subject light in parallel with the optical axis When using an optical system, it is necessary to use this object-side telecentric lens optical system in each imaging camera, which increases the number of parts, leading to an increase in the size, complexity, and cost of the apparatus. It was.
Further, the two imaging cameras are fixed with respect to the casing, and it is difficult to perform imaging with optical characteristics other than the preselected specifications.

JP 2003-124700 A

  The present invention has been made in view of the above circumstances, and the object of the present invention is to reduce the number of components, simplify the structure, reduce the size of the device, reduce the cost, etc. An object of the present invention is to provide an imaging apparatus that can image a subject (object) in detail over the whole or a part thereof and that can be applied particularly in a mounting process of an electronic component or the like.

An imaging apparatus according to the present invention is an imaging apparatus that divides subject light into a plurality of optical paths and images the subject on each of the optical paths, and is an object-side telecentric lens optical system that guides the principal ray of the subject light parallel to the optical axis And an optical path dividing element that divides the outgoing light of the object side telecentric lens optical system into a plurality of optical paths, and a plurality of imaging lens optical systems arranged on the plurality of optical paths divided by the optical path dividing element. It is said.
According to this configuration, the subject light passes through the object-side telecentric lens optical system, is then divided into a plurality of optical paths by the optical path dividing element, and is imaged by the plurality of imaging lens optical systems disposed on the respective optical paths. .
That is, even when the subject fluctuates from a predetermined imaging position or images a peripheral region, the object-side telecentric lens optical system can capture a highly accurate image that is not affected by the subject variation or the imaging region, Since multiple imaging lens optical systems share a single object-side telecentric lens optical system, the number of parts can be reduced compared to the case where each object-side telecentric lens optical system is provided, the structure is simplified, and the device is compact. And cost reduction can be achieved.

In the above configuration, the object-side telecentric lens optical system includes an aperture stop having a predetermined aperture on the most imaging side, and the optical path splitting element is disposed closer to the subject side than the aperture stop, and the object-side telecentric lens optical system A configuration that transmits and reflects outgoing light can be employed.
According to this configuration, the subject light that has passed through the object-side telecentric lens optical system can be easily divided into two optical paths while achieving cost reduction.

In the above configuration, the object-side telecentric lens optical system can employ a configuration in which a parallel light beam is emitted toward the optical path dividing element, and the optical path dividing element transmits and reflects the parallel light beam.
According to this configuration, since the subject light emitted from the object side telecentric lens optical system forms a parallel light beam, various imaging lenses having different optical characteristics can be used as the imaging lens optical system disposed on the downstream side of the optical path dividing element. An optical system can be applied, and versatility is improved.

In the above configuration, the plurality of imaging lens optical systems may include a small-field imaging lens optical system that captures a narrow range of the subject and a large-field imaging lens optical system that captures a wide range of the subject. .
According to this configuration, when the details of the subject are enlarged in detail, the small-field imaging lens optical system can be used for imaging, and when the entire subject is imaged, the large-field imaging lens. Imaging can be performed using an optical system. In other words, depending on the shooting mode, only one or both of the detail image and the entire image can be captured simultaneously.

In the above configuration, a bending element that bends the reflected light reflected by the optical path dividing element and guides it to the small-field imaging lens system or the large-field imaging lens system is disposed on the imaging side of the optical path dividing element. Can be adopted.
According to this configuration, since the subject light reflected by the optical path dividing element can be bent by the bending element and guided to the small-field imaging lens system or the large-field imaging lens system, for example, on the optical path transmitted through the optical path dividing element By arranging the large-field imaging lens optical system in the optical path, and by arranging the small-field imaging lens optical system on the optical path reflected by the optical path dividing element and bent by the bending element (for example, 90 degrees), the direction is changed. The imaging lens optical system can be arranged side by side, and the apparatus can be reduced in size and thickness as a whole.

The above configuration adopts a configuration including an object-side telecentric lens optical system and a casing that holds an optical path dividing element or a bending element, and the plurality of imaging lens optical systems are unitized so as to be detachable from the casing. Can do.
According to this configuration, since a plurality of imaging lens optical systems are unitized so as to be detachable from the casing, desired optical characteristics can be appropriately selected according to photographing requirements in a state where the object side telecentric lens optical system is shared. It can be exchanged for an imaging lens optical system.

In the above configuration, it is possible to employ a configuration in which a bending element that bends subject light and guides it to the object side telecentric lens optical system is disposed closer to the subject side than the object side telecentric lens optical system.
According to this configuration, for example, the subject light reflected from the upper side to the lower side is changed in the horizontal direction by the bending element and guided to the object-side telecentric lens optical system, thereby reducing the thickness of the apparatus. Can be achieved.

  According to the imaging apparatus having the above-described configuration, a subject such as an electronic component is entirely or partially detailed while achieving reduction in the number of parts, simplification of the structure, miniaturization of the apparatus, cost reduction, and the like. It is possible to obtain an image pickup apparatus that can take an image and can be applied particularly in a mounting process of an electronic component or the like.

DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, exemplary embodiments of the invention will be described with reference to the accompanying drawings.
1 to 12 show an embodiment of an imaging apparatus according to the present invention. FIG. 1 is a perspective sectional view showing the inside of the apparatus, FIG. 2 is a plan view of the apparatus, and FIG. 3 is a sectional view of the apparatus. 4 is a block diagram showing a large-field imaging optical system, FIG. 5 is a block diagram showing a small-field imaging optical system, FIG. 6 is a partially enlarged sectional view of an object-side telecentric lens optical system, and FIG. FIG. 8 is a partial sectional view showing a large-field imaging lens optical system, FIG. 9 is a partial sectional view showing a small-field imaging lens optical system, and FIG. 10 is a large field-of-view. FIG. 11 is a structural diagram showing the lens configuration of the small-field imaging optical system, and FIGS. 12 and 13 are aberration diagrams.

As shown in FIGS. 1 to 3, the imaging device includes a casing 10 that covers the whole, a first half mirror 20 as a refractive element, an object-side telecentric lens optical system 30, a second half mirror 40 as an optical path dividing element, A large-field imaging lens optical system 50 disposed on the optical path transmitted through the second half mirror 40; a total reflection mirror 60 disposed on the optical path reflected by the second half mirror 40 as a bending element that bends the subject light; The small-field imaging lens optical system 70 disposed on the optical path of the subject light reflected by the total reflection mirror 60, the annular illumination light source 80 disposed annularly above the first half mirror 20, and the first half mirror 20. The light source 90 for coaxial illumination etc. which are arrange | positioned below are provided.
In this imaging apparatus, the object-side telecentric lens optical system 30 and the large-field imaging lens optical system 50 form a large-field imaging optical system that images the subject OBJ over a wide range. The optical system 30 and the small-field imaging lens optical system 70 form a small-field imaging optical system that partially enlarges a narrow range of the subject OBJ and images in detail.

  As shown in FIGS. 1 to 3, the casing 10 is formed so that its longitudinal section is substantially L-shaped, and is held by a suction nozzle N and is a subject (electronic component) OBJ carried into a predetermined imaging position. A circular opening 11 through which subject light reflected from the light passes, a transparent anti-vibration glass 12 covering the opening 11, a holding frame 13 holding the light source 80, a holding frame 14 holding the first half mirror 20, and a light source 90. A holding plate 15 for holding, a holding cylinder 16 for holding the object side telecentric lens optical system 30, a holding frame 17 for holding the second half mirror 40, a holding frame 18 for holding the total reflection mirror 60, and a large-field imaging lens optical system 50. And a flange portion 19 having a mounting hole 19b for removably attaching the small-field imaging lens optical system 70, and the like.

The first half mirror 20 has a function of transmitting and reflecting light. As shown in FIGS. 1 and 3, the first half mirror 20 is substantially configured to bend the subject light emitted downward by the subject OBJ in the horizontal direction. It is fixed to the holding frame 14 in a state inclined by 45 degrees.
That is, the subject light emitted from the upper side to the lower side is reflected in the horizontal direction (direction change) and guided to the object-side telecentric lens optical system 30.
As described above, by arranging the first half mirror 20 (bending element) that bends the subject light on the subject side of the object side telecentric lens optical system 30, the subject light traveling in the vertical direction can be guided in the horizontal direction. And thinning of the apparatus can be achieved. In addition, since the light source 90 for coaxial illumination can be disposed behind (below) the first half mirror 20, useless space can be saved as a whole, and the apparatus can be downsized.

As shown in FIGS. 1 and 3, the light source 80 has an annular shape around the holding frame 13 provided in three stages in the vicinity of the lower portion of the opening 11 and in the upper region of the first half mirror 20 (near the subject side). Are formed by a plurality of light-emitting diodes fixed and arranged so as to irradiate the subject OBJ with illumination light from an oblique direction.
As shown in FIGS. 1 and 3, the light source 90 includes a plurality of light emitting diodes and light from the light emitting diodes fixed in a planar arrangement on the holding plate 15 in the lower (back) region of the first half mirror 20. The diffusing plate diffuses the first half mirror 20 and irradiates illumination light toward the object OBJ positioned above.

As shown in FIGS. 1 and 5, the object-side telecentric lens optical system 30 includes a first lens G1, a second lens G1, and a second lens G1, which are arranged in order from the subject side to the imaging surface side in the lens barrel 31. A lens G2, a third lens G3, and an aperture stop SD having a predetermined diameter provided in unit cases 51 and 71 described later are formed.
Here, as shown in FIGS. 3 and 4, the first lens G <b> 1 is a biconvex lens having a positive refractive power with a convex surface facing the object side and the imaging surface side.
As shown in FIGS. 3 and 4, the second lens G2 is a meniscus lens having a positive refractive power with a convex surface on the subject side and a concave surface on the imaging surface side.
As shown in FIGS. 3 and 4, the third lens G <b> 3 is a plano-concave lens having a negative refractive power with a plane facing the subject and a concave surface facing the imaging surface.
The lens barrel 31 that holds the three lenses G1, G2, and G3 is oriented so that the optical axis L is horizontal by being fitted to the holding cylinder 16.

That is, the subject light entering the object-side telecentric lens optical system 30 is formed so that its principal ray L1 is parallel to the optical axis L, as shown in FIGS.
Therefore, even when the subject OBJ fluctuates from a predetermined imaging position or when a peripheral area is imaged, a highly accurate image that is not affected by these fluctuations or the imaging area can be captured, and a large-field imaging optical system In addition, since the single object-side telecentric lens optical system 30 is shared for the small-field imaging optical system, the number of parts can be reduced as compared with the case where each object-side telecentric lens optical system is provided, and the structure is simplified. Can be reduced in size and cost.

Further, the object side telecentric lens optical system 30 is formed so that the luminous flux of the subject light that has passed through the third lens G3 is emitted as parallel constraints and guided to the second half mirror 40, as shown in FIG. .
Thus, by emitting as a parallel light flux, the arrangement of the second half mirror 40 as an optical path splitting element is facilitated, and the imaging arranged on the downstream side (imaging plane side) of the second half mirror 40. As the lens optical system, various imaging lens optical systems having different optical characteristics can be applied, and versatility is improved.

As shown in FIGS. 1 and 3, the second half mirror 40 is located downstream of the third lens G <b> 3 of the object side telecentric lens optical system 30 (on the imaging surface side) on the subject side of the aperture stop SD. It is disposed on the horizontal optical axis L at an angle of 45 degrees and is fixed to the holding frame 17, and allows the emitted light (passed through the third lens G3) of the object side telecentric lens optical system 30 to pass through as it is. The light path is divided into two light paths: a light path that travels straight and a light path that travels by reflecting downward by 90 degrees.
Here, since the second half mirror 40 is employed as the optical path splitting element, predetermined transmittance and reflectance can be easily selected, and it is easily mounted and fixed in the casing 10 in a narrow space. be able to.

As shown in FIGS. 3, 7 and 8, the large-field imaging lens optical system 50 includes a unit case 51, a unit case formed detachably with respect to a mounting hole 19 a formed in the flange portion 19 of the casing 10. 51, a fourth lens G4, a fifth lens G5, a sixth lens G6, a seventh lens G7, an eighth lens G8, which are arranged on the optical axis L in order from the subject side to the imaging plane side. An element 52 and the like are provided.
The unit case 51 is provided with an aperture stop SD having a predetermined aperture that forms part of the object-side telecentric lens optical system 30 on the subject side of the fourth lens G4.

Here, as shown in FIG. 8, the fourth lens G4 is a biconvex lens having a positive refractive power with a convex surface facing the subject and a convex surface facing the imaging surface.
As shown in FIG. 8, the fifth lens G5 is a biconcave lens having negative refractive power with a concave surface on the subject side and a concave surface on the imaging surface side, and is joined to the fourth lens G4.
As shown in FIG. 8, the sixth lens G6 is a biconcave lens having negative refractive power with a concave surface on the subject side and a concave surface on the imaging surface side.
As shown in FIG. 8, the seventh lens G7 is a biconvex lens having a positive refractive power with a convex surface on the subject side and a convex surface on the imaging surface side, and is joined to the sixth lens G6.
As shown in FIG. 8, the eighth lens G8 is a biconvex lens having a positive refractive power with a convex surface facing the subject and a convex surface facing the imaging surface.
The image sensor 52 is an area CCD that defines the imaging plane P. As described above, by using an area CCD that can image an area (surface) instead of a line (line) as the imaging element 52, the imaging time can be shortened. When this imaging apparatus is applied to a mounting line or the like, , The mounting speed can be increased and the productivity can be improved.

  Therefore, when the subject OBJ is imaged with a large field of view, the image is captured by the large field imaging optical system including the object side telecentric lens optical system 30 and the large field imaging lens optical system 50 as shown in FIG. That is, subject OBJ → first half mirror 20 (reflection) → object side telecentric lens optical system 30 (first lens G1 → second lens G2 → third lens G3) → second half mirror 40 (transmission) → aperture stop SD → Large field imaging lens optical system 50 (4th lens G4 → 5th lens G5 → 6th lens G6 → 7th lens G7 → 8th lens G8 → image sensor 52) A large field image is captured. .

  Further, since the large-field imaging lens optical system 50 is unitized and the unit case 51 is detachable from the casing 10 (the mounting hole 19a thereof), the object-side telecentric lens optical system 30 (the first one) In a state where the first lens G1, the second lens G2, and the third lens G3) are made common, it can be easily replaced with an imaging lens optical system having other optical characteristics as appropriate in accordance with a photographing request.

As shown in FIGS. 1 and 3, the total reflection mirror 60 is inclined at 45 degrees so as to be parallel to the second half mirror 40 on the image plane side and below the second half mirror 40. The object light that is disposed and fixed to the holding frame 18 and reflected downward by the second half mirror 40 is further bent and reflected in the horizontal direction, and is positioned downstream (imaging plane side). The small-field imaging lens optical system 70 is guided.
As described above, since the total reflection mirror 60 is employed as the bending element, it can be easily mounted and fixed in the casing 10 in a narrow space, and is disposed on the optical path transmitted through the second half mirror 40. The large-field imaging lens optical system 50 and the small-field imaging lens optical system 70 arranged on the optical path reflected by the second half mirror 40 and reflected by the total reflection mirror 60 can be arranged in parallel. Compared with the case where the total reflection mirror 60 is not provided, the overall apparatus can be reduced in size and thickness.

As shown in FIGS. 3, 7 and 9, the small-field imaging lens optical system 70 includes a unit case 71, a unit case formed detachably with respect to a mounting hole 19 b formed in the flange portion 19 of the casing 10. 71 includes a ninth lens G9, a tenth lens G10, an eleventh lens G11, an image sensor 72, and the like, which are arranged in order on the optical axis L from the subject side to the imaging plane side.
The unit case 71 is provided with an aperture stop SD having a predetermined aperture that forms a part of the object-side telecentric lens optical system 30 on the subject side of the ninth lens G9.

Here, as shown in FIG. 9, the ninth lens G9 is a biconvex lens having a positive refractive power with a convex surface on the subject side and a convex surface on the imaging surface side.
As shown in FIG. 9, the tenth lens G10 is a biconvex lens having a positive refractive power with a convex surface facing the subject and a convex surface facing the imaging surface.
As shown in FIG. 9, the eleventh lens G11 is a biconcave lens having negative refractive power with a concave surface on the subject side and a concave surface on the imaging surface side, and is joined to the tenth lens G10.
The image sensor 72 is an area CCD that defines the imaging plane P. As described above, by using an area CCD that can image an area (surface) instead of a line (line) as the imaging element 72, the imaging time can be shortened. When this imaging apparatus is applied to a mounting line or the like, , The mounting speed can be increased and the productivity can be improved.

  Therefore, when the subject OBJ is imaged with a small field of view, as shown in FIG. 5, the object OBJ is imaged with a small field imaging optical system including the object side telecentric lens optical system 30 and the small field imaging lens optical system 70. That is, subject OBJ → first half mirror 20 (reflection) → object side telecentric lens optical system 30 (first lens G1 → second lens G2 → third lens G3) → second half mirror 40 (reflection) → total reflection mirror 60 (reflection) → aperture stop SD → small field imaging lens optical system 70 (the ninth lens G9 → the tenth lens G10 → the eleventh lens G11 → the image sensor 72), a small field image is captured.

As described above, when imaging a wide range of the subject OBJ, the large-field imaging optical system (30, 50) is used. When imaging a narrow range of the subject OBJ in detail, the small-field imaging optical system (30, 70) is used. These imaging operations may be switched as needed when there is a single monitor, and only one image may be taken. If there are two monitors, large and small images can be taken simultaneously. May be imaged.
That is, according to the imaging apparatus, on the subject optical path, the single object-side telecentric lens optical system 30 (the first lens G1, the second lens G2, and the third lens G3) is disposed on the subject side, and downstream thereof. On the side, one optical path can be divided into two optical paths via the second half mirror 40, and a large-field image and a small-field image can be captured through each optical path, so that the subject OBJ fluctuates from a predetermined imaging position. Even in this case, both the large-field image and the small-field image can be taken as high-accuracy images, and a single object-side telecentric lens optical system 30 (first lens G1, second lens G2, third lens Since G3) is shared, the number of parts can be reduced compared to the case where each object side telecentric lens optical system is provided, the structure is simplified, the apparatus is downsized, the cost is reduced, etc. It can be achieved to.
Although the case where the aperture stop SD is provided in the unit cases 51 and 71 has been described in the above configuration, the aperture stop SD may be fixed to a part of the casing 10 instead of being provided in the unit cases 51 and 71.

  Next, specific specifications and various numerical data (setting values) of the large-field imaging optical system (the object-side telecentric lens optical system 30 and the large-field imaging lens optical system 50) are as follows. . As shown in FIG. 10, in the first lens G1 to the eighth lens G8, each surface is Si (i = 1 to 14), and the curvature radius of each surface Si is Ri (i = 1 to 14), The refractive index of each lens is Ni (i = 1 to 8), the Abbe number is νi (i = 1 to 8), and the distance (thickness, air interval) on the optical axis L is Di (i = 1 to 15). The outer diameter of each lens is represented by φi (i = 1 to 8).

<Specification specifications>
Working wavelength = 525 nm, focal length = 182.2 mm, imaging range = φ95 mm, aperture stop SD2 aperture = φ0.19 mm, brightness (F number) = 7.0, conjugate length (subject OBJ to imaging plane P) = 369 mm, total lens length = 169.5 mm
First lens G1 → φ1 = 90 mm, N1 = 1.7725, ν1 = 49.6
Second lens G2 → φ2 = 80 mm, N2 = 1.48749, ν2 = 70.2
Third lens G3 → φ3 = 68 mm, N3 = 1.78472, ν3 = 25.7
Fourth lens G4 → φ4 = 1.6 mm, N4 = 1.7725, ν4 = 49.6
5th lens G5 → φ5 = 2.0 mm, N5 = 1.51633, ν5 = 64.1
6th lens G6 → φ6 = 2.4 mm, N6 = 1.78472, ν6 = 25.7
7th lens G7 → φ7 = 3.2 mm, N7 = 1.62004, ν7 = 36.3
Eighth lens G8 → φ8 = 5.2 mm, N8 = 1.6968, ν8 = 55.5

<Curvature radius Ri (mm) of first lens G1 to eighth lens G8>
R1 = 193.425 mm, R2 = −401.1592 mm, R3 = 66.8901 mm, R4 = 231.478 mm, R5 = ∞, R6 = 105.5918 mm, R7 = 5.7548 mm, R8 = −5.7548 mm, R9 = 5.7094 mm, R10 = −3.0462 mm, R11 = 5.2632 mm, R12 = −4.3035 mm, R13 = 24.0046 mm, R14 = −11.0984 mm

<Surface spacing on the optical axis (mm)>
D1 = 199.4560 mm, D2 = 10.0000 mm, D3 = 1.0000 mm, D4 = 16.0000 mm, D5 = 9.0429 mm, D6 = 3.0000 mm, D7 = 112.8758 mm + (aperture stop SD) + 0.1926 mm, D8 = 1.0000 mm, D9 = 0.8000 mm, D10 = 1.5000 mm, D11 = 1.1000 mm, D12 = 2.0000 mm, D13 = 0.5000 mm, D14 = 1.5000 mm, D15 = 8.9570 mm

  Aberration diagrams showing spherical aberration, astigmatism, and distortion in the large-field imaging optical system configured as described above are the results shown in FIG. In the astigmatism in FIG. 12, S represents the aberration on the sagittal plane, and M represents the aberration on the meridional plane.

  Next, specific specification specifications and various numerical data (setting values) of the small-field imaging optical system (the object-side telecentric lens optical system 30 and the small-field imaging lens optical system 70) are as follows. . In addition, as shown in FIG. 11, in each of the first lens G1 to the third lens G3 and the ninth lens G9 to the eleventh lens G11, each surface is Si (i = 1 to 6, 15 to 19). The curvature radius of Si is Ri (i = 1 to 6, 15 to 19), the refractive index of each lens is Ni (i = 1 to 3, 9 to 11), and the Abbe number is νi (i = 1 to 3, 9). 11), the distance (thickness, air spacing) on the optical axis L is Di (i = 1 to 6, 16 to 21), and the outer diameter of each lens is φi (i = 1 to 3, 9 to 11). ).

<Specification specifications>
Use wavelength = 525 nm, focal length = 91.74 mm, imaging range = φ40 mm, aperture diameter of the aperture stop SD3 = φ4.06 mm, brightness (F number) = 7.0, conjugate length (subject OBJ to imaging plane P) = 401.45 mm, total lens length = 202 mm

First lens G1 → φ1 = 90 mm, N1 = 1.7725, ν1 = 49.6
Second lens G2 → φ2 = 80 mm, N2 = 1.48749, ν2 = 70.2
Third lens G3 → φ3 = 68 mm, N3 = 1.78472, ν3 = 25.7
9th lens G9 → φ9 = 10 mm, N9 = 1.84666, ν9 = 23.8
10th lens G10 → φ10 = 9 mm, N10 = 1.48749, ν10 = 70.2
Eleventh lens G11 → φ11 = 8 mm, N11 = 1.84666, ν11 = 23.8

<Curvature radii Ri (mm) of the first lens G1 to the third lens G3 and the ninth lens G9 to the eleventh lens G11>
R1 = 193.425 mm, R2 = −401.1592 mm, R3 = 66.8901 mm, R4 = 231.478 mm, R5 = ∞, R6 = 105.5918 mm, R15 = 39.5477 mm, R16 = −288.9141 mm, R17 = 8.3924 mm, R18 = −46.2059 mm, R19 = 8.3898 mm

<Surface spacing on the optical axis (mm)>
D1 = 199.4560 mm, D2 = 10.0000 mm, D3 = 1.0000 mm, D4 = 16.0000 mm, D5 = 9.0429 mm, D6 = 3.0000 mm, D16 = 112.8758 mm + (aperture stop SD) + 0.1926 mm, D17 = 4.0000 mm, D18 = 1.0640 mm, D19 = 2.8000 mm, D20 = 2.0000 mm, D21 = 17.1540 mm

  Aberration diagrams showing spherical aberration, astigmatism, and distortion in the small-field imaging optical system configured as described above are the results shown in FIG. In the astigmatism in FIG. 13, S represents the aberration on the sagittal plane, and M represents the aberration on the meridional plane.

In the above-described embodiment, the second half mirror 40 that divides the optical path dividing element into the optical path that transmits and the optical path that reflects is shown, and the large-field imaging lens optical system 50 and the small field-of-view as the multiple imaging lens optical systems Although two imaging lens optical systems 70 are shown, the present invention is not limited to this, and other optical path dividing elements that divide into a plurality of optical paths are adopted, and a plurality of imaging lens optical systems other than the two are applied. May be.
In the above-described embodiment, the case where the total reflection mirror 60 that further reflects the subject light reflected by the second half mirror 40 is used has been described. However, the present invention is not limited to this, and the total reflection mirror 60 is eliminated. Thus, the small-field imaging lens optical system 70 may be disposed on the optical path reflected by the second half mirror 40.

In the above-described embodiment, the large-field imaging lens optical system 50 is disposed on the optical path of the subject light transmitted through the second half mirror 40, and the small-field imaging lens is disposed on the optical path of the subject light reflected by the second half mirror 40. Although the case where the optical system 70 is disposed is shown, the present invention is not limited to this, and the large-field imaging lens system 50 and the small-field imaging lens system 70 may be interchanged.
In the above-described embodiment, the case where the first half mirror 20 is arranged on the upstream side (subject side) of the object side telecentric lens optical system 30 has been described. If it can arrange | position by (1), you may abolish the 1st half mirror 20. FIG.

1 is a perspective cross-sectional view showing an embodiment of an imaging apparatus according to the present invention and showing the inside of the apparatus. It is a top view of the imaging device shown in FIG. It is sectional drawing of the imaging device shown in FIG. It is a block diagram which shows the large visual field imaging optical system contained in an imaging device. It is a block diagram which shows the small-field imaging optical system contained in an imaging device. It is a partial expanded sectional view of the object side telecentric lens optical system contained in an imaging device. It is a fragmentary sectional view showing a large field imaging lens optical system and a small field imaging lens optical system included in the imaging device. It is a fragmentary sectional view showing a large field imaging lens optical system. It is a fragmentary sectional view showing a small field imaging lens optical system. It is a block diagram which shows the lens structure of a large-field imaging optical system. It is a block diagram which shows the lens structure of a small-field imaging optical system. It is an aberration diagram showing spherical aberration, astigmatism, and distortion in the large-field imaging optical system. It is an aberration diagram showing spherical aberration, astigmatism, and distortion in the small-field imaging optical system.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Casing 11 Opening part 12 Dust-proof glass 13, 14 Holding frame 15 Holding plate 16 Holding cylinder 17, 18 Holding frame 19 Flange part 19a, 19b Mounting hole 20 1st half mirror (bending element)
30 Object-side telecentric lens optical system 31 Lens barrel G1 First lens G2 Second lens G3 Third lens SD Aperture stop 40 Second half mirror (optical path dividing element)
50 Large-field imaging lens optical system 51 Unit case 52 Imaging element G4 Fourth lens G5 Fifth lens G6 Sixth lens G7 Seventh lens G8 Eighth lens 60 Total reflection mirror (bending element)
70 Small-field imaging lens optical system 71 Unit case 72 Imaging device G9 9th lens G10 9th lens G11 11th lenses 80, 90

Claims (7)

An imaging apparatus that divides subject light into a plurality of optical paths and images the subject on each optical path,
An object side telecentric lens optical system for guiding the principal ray of the subject light in parallel with the optical axis;
An optical path splitting element that splits outgoing light of the object side telecentric lens optical system into a plurality of optical paths;
A plurality of imaging lens optical systems disposed on a plurality of optical paths divided by the optical path dividing element;
An imaging apparatus comprising: The object-side telecentric lens optical system includes an aperture stop having a predetermined aperture on the most imaging side,
The optical path splitting element is disposed closer to the subject than the aperture stop and transmits and reflects the emitted light of the object side telecentric lens optical system;
The imaging apparatus according to claim 1. The object side telecentric lens optical system emits a parallel light beam toward the optical path dividing element,
The optical path splitting element transmits and reflects parallel light flux;
The imaging apparatus according to claim 1 or 2, wherein The plurality of imaging lens optical systems include a small-field imaging lens optical system that images a narrow range of a subject and a large-field imaging lens optical system that images a wide range of the subject.
The image pickup apparatus according to claim 1, wherein the image pickup apparatus is an image pickup apparatus. A bending element that bends the reflected light reflected by the optical path dividing element and guides it to the small-field imaging lens system or the large-field imaging lens system is disposed closer to the imaging side than the optical path dividing element.
The image pickup apparatus according to claim 2, wherein the image pickup apparatus is an image pickup apparatus. A casing for holding the object side telecentric lens optical system and an optical path dividing element or a bending element;
The plurality of imaging lens optical systems are unitized so as to be detachable from the casing.
The imaging apparatus according to claim 1, wherein A bending element that bends subject light and guides it to the object side telecentric lens optical system is disposed closer to the subject than the object side telecentric lens optical system.
The imaging apparatus according to claim 1, wherein:

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