JP2010250182A - Circular light source device, and microscope - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a circular light source device or the like achieving miniaturization and cost. <P>SOLUTION: The circular light source device includes: an annular light condensing lens 8; and a plurality of linear light source devices 100 annularly arranged along the incident surface of the light condensing lens 8, for emitting linear illumination light to the incident surface of the light condensing lens 8. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an annular light source device and a microscope.

  Conventionally, an annular light source device for emitting annular illumination light, such as a ring illumination of a microscope or an image measuring machine, or a strobe for a macro lens of a still camera, is known, and many LEDs are used as such an annular light source device. Have been proposed that are arranged concentrically (see, for example, Patent Document 1).

JP 2002-328094 A

However, the conventional annular light source device as described above has a problem in that it is increased in size by including a large number of LEDs, and the structure is complicated and the manufacturing cost increases.
Accordingly, the present invention has been made in view of the above problems, and an object thereof is to provide an annular light source device and a microscope that are reduced in size and cost.

In order to solve the above problems, the present invention
An annular condenser lens;
A plurality of linear light source devices that are arranged annularly along the incident surface of the condenser lens and emit linear illumination light onto the incident surface of the condenser lens;
An annular light source device is provided.
The present invention also provides
A microscope provided with the annular light source device is provided.

  ADVANTAGE OF THE INVENTION According to this invention, the annular light source device and microscope which aimed at size reduction and cost reduction can be provided.

(A) is sectional drawing which shows the structure of the microscope provided with the annular light source apparatus which concerns on embodiment of this invention, (b) is a perspective view which shows the structure of an annular light source apparatus. (A) is a perspective view which shows the structure of the linear light source device of a 1st modification, (b) is a front view of the reflective optical element used for a linear light source device, (c) is a reflective optical element from X-axis direction. (D) is a YZ cross-sectional view of the linear light source device (a JJ ′ cross-sectional view of (b)), (e) is a side view of the reflective optical element viewed from the Y-axis direction, and (f). FIG. 4 is an XZ sectional view of the linear light source device (II ′ sectional view of (b)), and (g) is a perspective view of the reflective optical element. It is a figure which shows the illumination intensity distribution in the condensing position of the reflective surface of a reflective optical element of the illumination light inject | emitted from the linear light source device of a 1st modification. (A) is a perspective view which shows the structure of the linear light source device of a 2nd modification, (b) is a front view of the reflective optical element used for a linear light source device, (c) is a reflective optical element from X-axis direction. (D) is a YZ cross-sectional view of the linear light source device (a JJ ′ cross-sectional view of (b)), (e) is a side view of the reflective optical element viewed from the Y-axis direction, and (f). FIG. 4 is an XZ sectional view of the linear light source device (II ′ sectional view of (b)), and (g) is a perspective view of the reflective optical element. It is a figure which shows the illumination intensity distribution in the condensing position of the reflective surface of the reflective optical element of the illumination light inject | emitted from the linear light source device of a 2nd modification. (A) is a perspective view which shows the structure of the linear light source device of a 3rd modification, (b) is a front view of the reflective optical element used for a linear light source device, (c) is a reflective optical element from X-axis direction. (D) is a YZ cross-sectional view of the linear light source device (a JJ ′ cross-sectional view of (b)), (e) is a side view of the reflective optical element viewed from the Y-axis direction, and (f). FIG. 4 is an XZ sectional view of the linear light source device (II ′ sectional view of (b)), and (g) is a perspective view of the reflective optical element. It is a figure which shows the illumination intensity distribution in the condensing position of the reflective surface of a reflective optical element of the illumination light inject | emitted from the linear light source device of a 3rd modification. (A) is a perspective view which shows the structure of the linear light source device of a 4th modification, (b) is a front view of the reflective optical element used for a linear light source device, (c) is a reflective optical element from X-axis direction. (D) is a YZ cross-sectional view of the linear light source device (a JJ ′ cross-sectional view of (b)), (e) is a side view of the reflective optical element viewed from the Y-axis direction, and (f). FIG. 4 is an XZ sectional view of the linear light source device (II ′ sectional view of (b)), and (g) is a perspective view of the reflective optical element. It is a figure which shows the illumination intensity distribution in the condensing position of the reflective surface of a reflective optical element of the illumination light inject | emitted from the linear light source device of a 4th modification. (A) is the front view of the reflective optical element in the linear light source device of a 5th modification, (b) is the side view which looked at the linear light source device from the X-axis direction, (c) is the Y-axis of the linear light source device. The side view seen from the direction, (d) is an XZ sectional view of the linear light source device (II ′ sectional view of (a)), (e) is a perspective view of the linear light source device. It is a figure which shows a mode that the emission surface of the reflective optical element in the linear light source device of the 5th modification was made into the inclined surface. (A) is a perspective view which shows a mode that the linear light source device of the 1st modification was combined with the fly eye integrator, (b) is the sectional drawing. It is a figure which shows the structure of a fly eye integrator. (A) is a figure which shows the angle characteristic in the entrance plane of a fly eye integrator at the time of using the linear light source device of a 1st modification in combination with a fly eye integrator, (b) is similarly in the exit surface of a fly eye integrator. It is a figure which shows an angle characteristic. It is a figure which shows a mode that the linear light source device of the 1st modification was applied to the imaging device.

A microscope having an annular light source device according to an embodiment of the present invention will be described with reference to the accompanying drawings.
As shown in FIG. 1A, the microscope 2 including the annular light source device 1 according to the present embodiment is disposed on the outer periphery of the first objective lens 4 and the first objective lens 4 in order from the sample 3 side. And includes an annular light source device 1 that emits annular illumination light, an aperture stop 5, a second objective lens 6, and an image sensor 7. The sample 3 is arranged conjugate with the image sensor 7 via the first objective lens 4, the aperture stop 5, and the second objective lens 6.
As shown in FIG. 1B, the annular light source device 1 has an annular condenser lens 8 having a diameter larger than that of the first objective lens 4 and an annular arrangement 8 along the incident surface of the condenser lens 8. It is arranged between two linear light source devices 100, the condensing lens 8 and each linear light source device 100, and includes an annular fly eye integrator 9 having substantially the same diameter as the condensing lens 8.

The fly-eye integrator 9 is configured by arranging a large number of elemental lenses having a regular hexagonal shape on the entrance surface and the exit surface, and the entrance surface of each element lens is connected to the sample 3 via the condenser lens 8. They are arranged so as to be conjugate. Note that the fly-eye integrator 9 is not limited to this, and for example, one having an entrance surface and an exit surface made of rectangular element lenses can be used.
Each of the eight linear light source devices 100 emits linear illumination light toward the condenser lens 8 via the fly-eye integrator 9, and all have the same configuration.
Here, in describing the detailed configuration of the linear light source device 100, other linear light source devices applicable to the annular light source device 1 according to the present embodiment in the same manner as the linear light source device 100 are first modified. An example to a fifth modification will be described in advance.

(First modification)
As shown in FIG. 2A, the linear light source device 10 of the first modified example includes a light source 11 and a reflective optical element 15 including a reflective surface 15a that reflects light from the light source 11 and condenses the light into a linear shape. It consists of.
The reflecting surface 15a of the reflecting optical element 15 has an intersection point of the optical axis AX and the reflecting surface 15a as an origin O, a normal line of the reflecting surface 15a at the origin O is a Z axis, and a straight line passing through the origin O perpendicular to the Z axis is X When the Y axis is a straight line that is perpendicular to the axis, the Z axis, and the X axis and passes through the origin O, the cross sectional shape of the XZ plane is a parabola, and the cross sectional shape of the YZ plane is an ellipse having a long axis that matches the Z axis. Thus, it is an anamorphic aspherical surface represented by the following definitional expressions (1) to (4) (the parabola is referred to as a parabola 16 and the ellipse is referred to as an ellipse 17). The definitions of the origin O, the X axis, the Y axis, and the Z axis are the same in all the linear light source devices described later.

(1) z = {(x ² / r _p ) + (y ² / r _e )} / [1 + √ {1- (1 + K _e ) (y / r _e ) ² }]
(2) r _p = 2f ₁
(3) K _e = − {(f ₁ −f ₂ ) / (f ₁ + f ₂ )} ²
_{(4) r e = (2f} 1 f 2) / (f 1 + f 2)
However,
f ₁ : Distance between the reflecting surface 15a and the light source 11 (distance between the origin O and the light source 11)
f ₂ : distance r _p between the reflecting surface 15 a and the converging position 18 of the reflecting surface 15 a: radius of curvature of the parabola 16 K _e : conic constant of the ellipse 17 r _e : radius of curvature of the ellipse 17

  From the above definition formulas, the focal position of the parabola 16 of the reflecting surface 15a of the reflective optical element 15 and the first focal position of the ellipse 17 coincide. In the linear light source device 10 of the present modification, the light source 11 is disposed at this position, whereby the condensing position 18 of the reflecting surface 15a coincides with the second focal position of the ellipse 17. With such a configuration, the reflective optical element 15 reflects the light beam emitted from the light source 11 by the reflection surface 15a, thereby converting it into a parallel light beam in the XZ plane, and the second focal position of the ellipse 17 (in the YZ plane ( Therefore, the light beam from the light source 11 can be efficiently converted into a linear light beam without loss of light quantity in a narrow space.

Specifically, when the external dimensions of the reflective surface 15a of the reflective optical element 15 are 10 × 10, f ₁ = 10, and f ₂ = 20, r _p = 20, K _e = 0.111, r _e = 13. 3, and it can be seen that the luminous flux is linearly collected in a plane including the condensing position 18 of the reflecting surface 15 a (a plane 18 a perpendicular to the Z axis) as shown in FIG. The unit of length listed in this specification is “mm”, but the unit is not limited to this because the same optical performance can be obtained even when proportionally enlarged or reduced.

Under the above configuration, the light beam emitted from the light source 11 in the linear light source device 10 is reflected by the reflecting surface 15a of the reflective optical element 15 so as to be efficiently collected in a linear shape at the condensing position 18. In this manner, the linear light source device 10 can emit linear illumination light.
The reflective optical element 15 has a reflecting mirror shape formed by vapor-depositing chromium or aluminum on the glass surface, vapor-deposited chromium or aluminum on a molded product made of a thermoplastic resin, or metal sheet metal processing or cutting. It is preferable to use one formed. In addition, it is preferable that the light source 11 in the linear light source device 10 is supported by the support member by forming an opening at the origin O portion of the reflection surface 15a of the reflective optical element 15 and inserting the support member. These are the same in the second to fourth modifications described later.

(Second modification)
In the second modified example and each modified example described later, parts having the same configuration as in the first modified example are denoted by the same reference numerals, description thereof is omitted, and different parts are described in detail.
As shown in FIG. 4A, the linear light source device 20 of the second modified example includes a light source 11 and a reflective optical element 25 including a reflective surface 25a that reflects light from the light source 11 and condenses it in a linear shape. It consists of.
The reflecting surface 25a of the reflecting optical element 25 is an ellipse having a short axis whose cross-sectional shape by the XZ plane is a parabola and whose cross-sectional shape by the YZ plane coincides with the Z axis, and the following definition formulas (1), (5 ) To (8) are anamorphic aspherical surfaces (the parabola is referred to as a parabola 26 and the ellipse is referred to as an ellipse 27).

(1) z = {(x ² / r _p ) + (y ² / r _e )} / [1 + √ {1- (1 + K _e ) (y / r _e ) ² }]
(5) a = √ (b ₂ + d ₂ )
(6) r _p = 2f ₁
(7) K _e = (a ² −f ₁ ² ) / (f ₁ ² )
^{_{(8) r e = a 2}} / f 1
However,
f ₁ : distance a between the light collection position 28 of the reflecting surface 25a and the midpoint 29 (center of the ellipse 227) of the light source 11 and the reflecting surface 25a : Major radius b of ellipse 27 : Short radius d of ellipse 27 : Distance between the condensing position 28 of the reflecting surface 25a, the midpoint 29 of the light source 11, and the light source 11 (distance between the Z axis and the light source 11)
r _p : radius of curvature of parabola 26 K _e : conic constant of ellipse 27 r _e : radius of curvature of ellipse 27

  From the above definition formulas, the focal position of the parabola 26 of the reflecting surface 25a of the reflective optical element 25 and the first focal position of the ellipse 27 coincide. In the linear light source device 20 of the present modification, the light source 11 is disposed at this position, whereby the condensing position 28 of the reflecting surface 25a coincides with the second focal position of the ellipse 27. With this configuration, the reflecting optical element 25 reflects the light beam emitted from the light source 11 by the reflecting surface 25a, thereby converting the light beam 11 into a parallel light beam in the XZ plane, and the second focal position of the ellipse 27 in the YZ plane ( Therefore, the light beam from the light source 11 can be efficiently converted into a linear light beam in a narrow space.

Specifically, when the external dimensions of the reflecting surface 25a of the reflecting optical element 25 are 10 × 10, f ₁ = 10, and d = 5, r _p = 20, K _e = 0.25, r _e = 12. 5, it can be seen that the luminous flux is linearly collected in the plane 28a including the condensing position 28 of the reflecting surface 25a as shown in FIG. Further, as shown in FIG. 5, the condensed linear light beam does not cause a shadow of the light source 11. This is because the light source 11 and the condensing position 28 of the reflecting surface 25a are in different directions when viewed from the origin O, and the light beam reflected by the reflecting surface 25a is not vignetted by the light source 11.
With the above configuration, the linear light source device 20 can achieve the same effects as the linear light source device 10 of the first modification.

(Third Modification)
As shown in FIG. 6A, the linear light source device 30 of the third modified example includes a light source 11 and a reflective optical element 35 including a reflective surface 35a that reflects light from the light source 11 and condenses it linearly. It consists of.
The reflecting surface 35a of the reflecting optical element 35 is a parabola having a cross-sectional shape in the XZ plane and a circular cross-sectional shape in the YZ plane, and is a curved surface represented by the following definition formula (9) (the parabola is a parabola). 36, the circle is referred to as circle 34).
(9) z = f ₁ −√ {(f ₁ −x ² / 4f ₁ ) ² −y ² }
However,
f ₁ : Distance between the reflective surface 35a and the light source 11 (distance between the center of the circle 34 and the reflective surface 35a)

  From the above definition formulas, the focal position of the parabola 36 of the reflecting surface 35a of the reflecting optical element 35 coincides with the center of the circle 34. In the linear light source device 30 of the present modification, the light source 11 is disposed at this position, whereby the condensing position 38 of the reflecting surface 35a coincides with the center of the circle 34. With such a configuration, the reflective optical element 35 reflects the light beam emitted from the light source 11 by the reflection surface 35a, thereby converting it into a parallel light beam in the XZ plane, and the center (condensing position) of the circle 34 in the YZ plane. 38), the light beam from the light source 11 can be efficiently converted into a linear light beam in a narrow space.

Specifically, when the external dimensions of the reflective surface 35a of the reflective optical element 35 are 10 × 10 and f ₁ = 10, the light flux is within a plane 38a including the condensing position 38 of the reflective surface 35a as shown in FIG. It can be seen that is accurately collected in a linear shape. In addition, since the reflective surface 35a is a rotationally symmetrical shape, the reflective optical element 35 also has the advantage that manufacture is easy.
With the above configuration, the linear light source device 30 can achieve the same effects as the linear light source device 20 of the first modification.

(Fourth modification)
As shown in FIG. 8 (a), the linear light source device 40 of the fourth modified example divides the reflective optical element 15 in the first modified example into two on the YZ plane, and the upper half (FIG. 2 (a) paper surface Only the upper half) is provided as the reflective optical element 45, and the other configurations are the same as in the first modification. In addition, the reflective optical element 45 of this modification is produced so that an external shape may become a square seeing from the front, as shown in FIG.8 (b).

In the linear light source device 40 having such a configuration, when the external dimensions of the reflective surface 45a of the reflective optical element 45 are 10 × 10, f ₁ = 10, and f ₂ = 20, as shown in FIG. It can be seen that the luminous flux is linearly collected in the plane 48 a including the condensing position 48. Moreover, as shown in FIG. 9, the shadow of the light source 11 is not formed in the central portion of the condensed linear light flux. This is because light that is likely to be vignetted by the light source 11, that is, light traveling on the optical axis AX, can be condensed at the end of the linear condensing position 48 out of the light flux reflected by the reflecting surface 45a. It is.

With the above configuration, the linear light source device 40 can achieve the same effects as the linear light source device 10 of the first modification.
In this modification, the reflection optical element 15 of the first modification is divided into two on the YZ plane as described above, and the upper half thereof is used as the reflection optical element 45. However, the present invention is not limited to this. It is also possible to divide the lower half of the element 15 or the reflective optical element 35 in the third modified example into two on the YZ plane, and use the upper half or the lower half of them.

(5th modification)
As shown in FIG. 10, the linear light source device 50 of the fifth modified example includes a light source 11 and a reflective optical element 55 that includes a reflection surface 55 a that reflects light from the light source 11 and collects the light in a linear shape. .
The reflective optical element 55 in this modification is a prismatic prism member having a square cross-section extending in the Z-axis direction, and a transparent medium (with a refractive index greater than 1 selected according to the wavelength of light from the light source 11). For example, it is made of glass or resin. The reflective surface 55a for internally reflecting light is provided at one end of the reflective optical element 55, and the other end is an exit surface 55b for emitting light. The exit surface 55b is perpendicular to the Z axis and includes the condensing position 58 of the reflection surface 55a.

The reflecting surface 55a of the reflecting optical element 55 has the same shape as the reflecting surface 15a of the reflecting optical element 15 of the first modification (the cross-sectional shape by the XZ plane is a parabola 16, and the cross-sectional shape by the YZ plane is Z-axis). An anamorphic aspheric surface that becomes an ellipse 17 having a long axis that coincides, and a hemispherical recess 51 is provided at the center as shown in FIG.
The light source 11 is sealed or adhered by a medium having substantially the same refractive index as that of the reflective optical element 55 in the concave portion 51 of the reflective optical element 55, whereby the light source 11 has the first focal point of the ellipse 17 on the reflective surface 55a. And the focal point of the parabola 16.
The light source 11 is preferably a solid-state light source such as a semiconductor laser or a light emitting diode. This makes it possible to reduce the size of the light source 11 and the reflective optical element 55, and thus the linear light source device 50. This also applies to each of the above modifications.

With the above configuration, the light beam emitted from the light source 11 in the linear light source device 50 enters the reflective optical element 55, is internally reflected by the reflective surface 55a, and then linearly reaches the condensing position 58 on the exit surface 55b. It will be focused on. In this manner, the linear light source device 50 can emit linear illumination light from the exit surface 55b of the reflective optical element 55.
As described above, in the present modification, the reflection surface 55a of the reflection optical element 55 has the same shape as the reflection surface 15a of the reflection optical element 15 of the first modification. However, the present invention is not limited to this, and the second modification example. It is of course possible to have the same shape as the reflecting surface of the reflective optical element of the fourth modification.

  Further, the reflective optical element 55 of the present modification is advantageous in that it can be easily manufactured and can be reduced in cost by the above-described configuration. However, the present invention is not limited to this, and the diffusion surface or diffraction grating is provided on the exit surface 55b. Etc. are also provided with the advantage that an optical function can be added. For example, as shown in FIG. 11, the emission surface 55b is inclined as an inclined surface with respect to the Z axis, and the effect of the declination prism is added, so that the emission direction of the linear illumination light emitted from the emission surface 55b is arbitrary. It becomes possible to set to.

Next, the linear light source device 100 provided in the annular light source device 1 according to the present embodiment will be described.
As shown in FIG. 1, the linear light source device 100 has the same configuration as that of the linear light source device 50 of the fifth modified example, and reflects the light from the light source 11 and the light source 11 to condense in a linear shape. And a reflecting optical element 55 having a reflecting surface 55a.
In detail, the reflecting optical element 65 has a reflecting optical element 55 of the fifth modified example that has a thin tip at the exit surface 55b (the thickness in the radial direction is small with respect to the optical axis), thereby reflecting the reflecting surface. The prism portion that does not contribute to the progression of the light beam reflected by 55a is eliminated to reduce the size. In addition, the exit surface 55b is inclined with respect to the optical axis, whereby the exit direction of the illumination light emitted from the exit surface 55b can be deflected and appropriately guided to the fly eye integrator 9. Further, the reflective optical element 55 having such a configuration is arranged so as to be inclined with respect to the optical axis of the first objective lens 4, thereby further reducing the size of the annular light source device 1 as a whole. When viewing 3 from the side of the annular light source device 1, the annular light source device 1 can be prevented from obstructing.

In the microscope 2 including the annular light source device 1 according to the present embodiment having the above-described configuration, the light emitted from the light source 11 of the linear light source device 100 is incident on the reflective optical element 55 and internally reflected by the reflecting surface 55a. Thereafter, the light is condensed linearly at the light condensing position on the emission surface 55b, and linear illumination light is emitted from the emission surface 55b. Here, as described above, since the linear light source device 100 is arranged in a ring shape so as to surround the first objective lens 4, the linear illumination light emitted from each of the linear light source devices 100 is used. A substantially annular illumination light is formed.
The substantially annular illumination light thus formed is incident on each element lens of the fly-eye integrator 9, is condensed by each element lens, and a light source image (secondary) on each exit surface (sample 3 side). After the light source is formed, the light is emitted with uniform radiation angle characteristics. In this way, the illumination light emitted from each element lens is condensed by the condenser lens 8 and irradiated onto the sample 3 in a superimposed manner, thereby realizing ring illumination without illuminance unevenness. .
The light from the sample 3 that has been ring-illuminated in this manner forms an image on the imaging surface of the imaging element 7 through the first objective lens 4, the aperture stop 5, and the second objective lens 6 in order. As a result, the image of the sample 3 is picked up by the image pickup device 7 and displayed on a monitor (not shown) separately provided in the microscope 2. As described above, the user can observe the sample 3 by ring illumination using the microscope 2.

  As described above, according to the present embodiment, the annular light source device 1 is configured by using the eight linear light source devices 100 arranged in a ring shape as described above, so that a large number of LEDs are concentrically arranged. The number of light sources can be greatly reduced as compared with the annular light source device, and downsizing (particularly downsizing in the radial direction of the first objective lens 4) and cost reduction can be realized. Moreover, since the annular light source device 1 according to the present embodiment can form a large number of pseudo light sources by the fly eye integrator 9, ring illumination without uneven illuminance can be realized.

  Note that the linear light source devices 10, 20, 30, 40, 50 and the linear light source device 100 of the first to fifth modifications are only applicable to the annular light source device 1 according to the present embodiment. Instead, it can be used in combination with a fly-eye integrator or applied to an imaging apparatus as described below.

As shown in FIG. 12, the case where the linear light source device 10 of the first modified example is used in combination with the fly eye integrator 60 will be described.
The fly's eye integrator 60 is disposed at the condensing position 18 of the reflecting surface 15a of the reflecting optical element 15, and is formed by stacking 5 × 21 (a total of 105) square prism-shaped element lenses as shown in FIG. . Each element lens has a square entrance surface and an exit surface, and the outer shape of the fly-eye integrator 60 is a rectangle extending in the X-axis direction when viewed from the light source 11 side. In addition, it is preferable that the fly eye integrator 60 is produced by processing of glass lenses having a quadrangular prism shape or processing such as a plastic mold.

Specifically, each element lens is made of polycarbonate (refractive index n = 1.585), the focal length is 0.833, and the dimensions of the entrance surface and the exit surface are 0.5 × 0.5. In addition, the entrance surface and the exit surface of each element lens are arranged at the focal positions of each other, the thickness is 1.32, and the respective curvature radii are 0.4875. As in the first modification, the external dimensions of the reflective surface 15a of the reflective optical element 15 are 10 × 10, f ₁ = 10, f ₂ = 20, r _p = 20, K _e = 0.111, r _e. = 13.333. The light source 11 is a square surface-emitting light source having an outer dimension of 1 × 1.

  With the above configuration, the light beam emitted from the light source 11 of the linear light source device 10 is reflected by the reflection surface 15a of the reflective optical element 15 and is efficiently condensed into a linear shape at the condensing position 18. Thereby, linear illumination light is irradiated to the fly eye integrator 60, and illumination light enters each element lens. Each light incident on each element lens is condensed by each element lens to form a light source image (secondary light source) on each exit surface, and then emitted with uniform radiation angle characteristics.

  From FIG. 14A, among the light beams reflected by the reflecting surface 15a of the reflecting optical element 15, the light beam (dotted line) reflected by the ellipse 17 portion of the reflecting surface 15a has a wide angle characteristic. It can be seen that the light beam (solid line) reflected by the parabola 16 has a narrow angular characteristic. On the other hand, it can be seen from FIG. 14B that these light fluxes that have passed through the fly-eye integrator 60 have uniform and wide angular characteristics. Accordingly, the linear illumination light emitted from the linear light source device 10 is converted into illumination light having a uniform radiation angle characteristic by the fly eye integrator 60 and illuminating a substantially square illumination region in a superimposed manner. You can see that

  Further, the fly eye integrator 60 is not limited to the one in which the entrance surface and the exit surface are configured by square element lenses, and the one in which the entrance surface and the exit surface are configured by regular hexagonal element lenses can also be used. In particular, it is suitable for an apparatus that requires a circular illumination area such as a microscope. Further, a mosaic type fly-eye lens composed of element lenses having different shapes of the entrance surface and the exit surface can also be used. In this case, the shape of the exit surface is preferably a rectangular shape having a short side in the X-axis direction and a long side in the Y-axis direction in consideration of the angle characteristics shown in FIG.

Further, as shown in FIG. 15, a case where the linear light source device 10 of the first modification is applied to an imaging device 70 will be described.
The imaging device 70 includes an imaging lens 72 and an imaging element 73 that are sequentially arranged upward from the stage 71 side on which the sample 3 is placed, and a collection unit that is sequentially arranged obliquely upward from the stage 71 side. The optical lens 74, the slit 75, and the linear light source device 10 are provided.
The slit 75 has an opening extending in the direction perpendicular to the paper surface of FIG. 15, and is disposed at the light condensing position 18 of the linear light source device 10. The image sensor 73 is composed of a one-dimensional image sensor arranged so as to extend in a direction perpendicular to the paper surface of FIG. The slit 75 is arranged conjugate with the sample 3 via the condenser lens 74, and the sample 3 is arranged conjugate with the imaging element 73 via the imaging lens 72.

  Under such a configuration, linear illumination light emitted from the linear light source device 10 (linear illumination light extending in the direction perpendicular to the sheet of FIG. 15) is applied to the slit 75. The illumination light that has passed through the slit 75 is condensed by the condenser lens 74 and the image of the slit 75 is projected onto the sample 3 on the stage 71. The light emitted from the sample 3 thus illuminated is imaged on the imaging surface of the imaging element 73 via the imaging lens 72. Here, a two-dimensional image of the sample 3 can be acquired by driving the stage 71 and moving the sample 3 in a direction perpendicular to the image of the slit 75 (left and right direction in FIG. 15). .

  The imaging device 70 described above illuminates and reflects the sample 3 obliquely from above. However, the imaging device 70 is not limited thereto, and constitutes an imaging device that performs coaxial epi-illumination, transmitted illumination, and the like using the linear light source device 10. You can also. Further, the imaging device 70 is not limited to the linear light source device 10 of the first modified example, and linear light source devices of other modified examples can be applied.

DESCRIPTION OF SYMBOLS 1 Ring light source device 2 Microscope 8 Condensing lens 9 Fly eye integrator 10, 20, 30, 40, 50, 100 Linear light source device 11 Light source 15, 25, 35, 45, 55 Reflective optical element 15a, 25a, 35a, 45a, 55a Reflecting surface 16, 26, 36 Parabola 17, 27 Ellipse 34 Circle 18, 28, 38, 48, 58 Condensing position AX Optical axis O Origin

Claims (14)

An annular condenser lens;
A plurality of linear light source devices that are arranged annularly along the incident surface of the condenser lens and emit linear illumination light onto the incident surface of the condenser lens;
An annular light source device comprising:   2. The optical integrator comprising a plurality of lens elements arranged in an annular shape and substantially the same diameter as the condenser lens, between the condenser lens and the plurality of linear light source devices. The annular light source device described. The linear light source device includes a light source and a reflective optical element including a reflective surface that reflects light from the light source and collects the light in a linear shape,
The reflecting surface of the reflecting optical element has an intersection between an optical axis and the reflecting surface as an origin, a normal line of the reflecting surface at the origin as a Z axis, and a straight line perpendicular to the Z axis and passing through the origin as an X axis. The cross-sectional shape by the XZ plane is a parabola when the straight line passing through the origin perpendicular to the Z-axis and the X-axis is a parabola, and the cross-sectional shape by the YZ plane is an ellipse or a circle. An annular light source device according to claim 1 or 2. The reflective surface of the reflective optical element in the linear light source device has a shape of at least a part of an ellipse having a long axis whose cross-sectional shape by the YZ plane coincides with the Z axis. Defined,
The annular light source device according to claim 3, wherein the light source is disposed at a focal position of the ellipse.
z = {(x ² / r _p ) + (y ² / r _e )} / [1 + √ {1− (1 + K _e ) (y / r _e ) ² }]
r _p = 2f ₁
K _e = − {(f ₁ −f ₂ ) / (f ₁ + f ₂ )} ²
r _e = (2f ₁ f ₂ ) / (f ₁ + f ₂ )
However,
f ₁ : distance between the reflecting surface and the light source f ₂ : distance between the reflecting surface and the condensing position of the reflecting surface r _p : radius of curvature of the parabola of the reflecting surface K _e : the ellipse of the reflecting surface Conic constant r _e : radius of curvature of the ellipse of the reflecting surface The reflective surface of the reflective optical element in the linear light source device has a shape of at least a part of an ellipse having a short axis whose cross-sectional shape by the YZ plane coincides with the Z axis, and the ellipse is expressed by the following equation: Defined,
The annular light source device according to claim 3, wherein the light source is disposed at a focal position of the ellipse.
z = {(x ² / r _p ) + (y ² / r _e )} / [1 + √ {1− (1 + K _e ) (y / r _e ) ² }]
a = √ (b ₂ + d ₂ )
r _p = 2f ₁
K _e = (a ² −f ₁ ² ) / (f ₁ ² )
r _e = a ² / f ₁
However,
f ₁ : Distance a between the condensing position of the reflecting surface and the midpoint of the light source and the reflecting surface : Ellipse major radius b of the reflecting surface : Short radius d of the ellipse of the reflecting surface : The condensing position of the reflecting surface and the distance r _p between the light source midpoint and the light source r _p : the radius of curvature of the parabola of the reflecting surface K _e : the elliptical conic constant r _{e of the} reflecting surface: the reflecting surface Radius of curvature of the ellipse The reflective surface of the reflective optical element in the linear light source device has a cross-sectional shape by a YZ plane having a shape of at least a part of a circle, and the circle is defined by the following equation:
The annular light source device according to claim 3, wherein the light source is disposed at a center of the circle.
z = f ₁ −√ {(f ₁ −x ² / 4f ₁ ) ² −y ² }
However,
f ₁ : distance between the reflecting surface and the light source   The annular light source device according to claim 4 or 6, wherein the reflective optical element in the linear light source device includes only one of the reflective surfaces divided by a YZ plane.   The reflective optical element in the linear light source device is composed of a prism member made of a medium having a refractive index greater than 1, and internally reflects light from the light source on the reflective surface and collects it linearly on the exit surface. The annular light source device according to claim 3, wherein the annular light source device emits light.   The annular light source device according to claim 8, wherein the exit surface of the reflective optical element in the linear light source device is inclined with respect to the Z-axis. The reflective optical element in the linear light source device has a small thickness in the Y-axis direction toward the exit surface,
The annular light source device according to claim 9, wherein the linear light source device is disposed to be inclined with respect to an optical axis of the condenser lens.   The annular light source device according to any one of claims 3 to 10, wherein the light source in the linear light source device is a solid light source.   The annular light source device according to claim 11, wherein the solid-state light source is a light emitting diode.   The annular light source device according to claim 11, wherein the solid-state light source is a semiconductor laser.   A microscope comprising the annular light source device according to any one of claims 1 to 13.