JP5942599B2 - Image shooting device - Google Patents

Description

  The present invention relates to an image photographing apparatus.

  Patent Document 1 discloses an invention of an image capturing apparatus including an illumination unit and a diffusion plate. In this image capturing device, the light output from the illumination unit is diffused by the diffusion plate and then irradiated to the object, and the light diffused and reflected by the object out of the light irradiated to the object passes through the objective lens. Then, the image is received by the imaging unit, and an image of the object is acquired. Since the light diffused by the diffusing plate is irradiated to the object, the directivity of the light irradiated to the object is lowered. Thus, since light is irradiated to a target object from various directions, generation | occurrence | production of halation can be suppressed.

JP 2002-72097 A

  When the aperture angle of the objective lens (the angle at which the diameter of the entrance pupil of the objective lens extends from the observation point of the target object) is large, the degree of freedom in the arrangement of the diffuser plate is limited. The directivity of the emitted light is insufficiently reduced, and the halation suppressing effect cannot be sufficiently obtained.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide an image photographing apparatus capable of obtaining a sufficient halation suppression effect even when the aperture angle of the objective lens is large. To do.

  An image capturing apparatus according to the present invention includes an illumination unit that outputs light, a transmission-type diffusion plate that diffuses the light output from the illumination unit and irradiates the object, and the object out of the light irradiated to the object. An objective lens that inputs light that has been diffusely reflected, a slit that defines a linear field of view in the first direction together with the objective lens, and light that has passed through the slit is split in a second direction perpendicular to the first direction. It comprises a spectroscope and an imaging unit that receives light split by the spectroscope and acquires a two-dimensional image. Further, in the present invention, the transmission type diffuser plate does not penetrate into the visual field area, and at least in the conical area and the outside of the visual field area with the observation point of the object in the visual field area as the apex and the objective lens as the bottom surface. It arrange | positions so that a part may exist, It is characterized by the above-mentioned.

  The image photographing apparatus of the present invention preferably further includes a first light shielding portion that is provided between the transmissive diffusion plate and the objective lens within the conical region and outside the visual field region and shields light directed toward the objective lens. In addition, it is also preferable to further include a second light-shielding unit that blocks light that goes straight to the observation point from the light output from the illumination unit.

  According to the present invention, even if the aperture angle of the objective lens is large, a sufficient halation suppression effect can be obtained.

It is a figure which shows the structure of the image imaging device 1 of this embodiment. It is a figure which shows the two-dimensional image acquired in the Example. It is a figure which shows the intensity distribution on the broken line in FIG. It is a figure which shows the two-dimensional image acquired in the comparative example. It is a figure which shows intensity distribution on the broken line in FIG.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the accompanying drawings. In the description of the drawings, the same elements are denoted by the same reference numerals, and redundant description is omitted.

  FIG. 1 is a diagram illustrating a configuration of an image capturing device 1 according to the present embodiment. In the figure, an XYZ orthogonal coordinate system is shown for convenience of explanation. The image capturing apparatus 1 includes illumination units 11A and 11B, transmissive diffusion plates 12A and 12B, first light shielding units 13A and 13B, second light shielding units 14A and 14B, an objective lens 15, a slit 16, a spectroscope 17, and an imaging unit 18. Is provided.

  The illumination unit 11A, the transmissive diffusion plate 12A, the first light shielding unit 13A, and the second light shielding unit 14A are arranged on the −Y direction side with respect to the optical axis of the objective lens 15. The illumination unit 11B, the transmissive diffusion plate 12B, the first light shielding unit 13B, and the second light shielding unit 14B are arranged on the + Y direction side with respect to the optical axis of the objective lens 15.

  The illumination unit 11A outputs light toward the transmissive diffusion plate 12A. The illuminator 11B outputs light toward the transmissive diffusion plate 12B. Each of the illumination units 11A and 11B includes, for example, a halogen lamp, a xenon lamp, a light emitting diode, or a laser diode.

  The transmissive diffusion plate 12 </ b> A diffuses the light output from the illumination unit 11 </ b> A and irradiates the object 3 placed on the sample stage 2 with light. The transmissive diffusion plate 12B diffuses the light output from the illumination unit 11B and irradiates the object 3 with light. Each of the transmissive diffusion plates 12A and 12B can irradiate the object 3 with light having low directivity.

  The objective lens 15 inputs light that is diffused and reflected by the object 3 among the light irradiated to the object 3 from the transmissive diffusion plates 12A and 12B. The slit 16 has an opening 16 a having a width in the X direction larger than the width in the Y direction, and defines a line-shaped visual field region in the X direction together with the objective lens 15. The spectroscope 17 splits the light that has passed through the opening 16a of the slit 16 in the Y direction. The imaging unit 18 receives the light separated by the spectroscope 17 and acquires a two-dimensional image. The X direction of the two-dimensional image acquired here represents the position of the object 3 in the X direction, and the Y direction of the two-dimensional image represents the wavelength.

  Each of the transmissive diffusion plates 12A and 12B does not penetrate into the field of view defined by the objective lens 15 and the opening 16a of the slit 16, and the objective point 3 of the object 3 in the field of view is used as the apex. The lens 15 is disposed so that at least a part thereof exists in a conical region with the entrance pupil of the lens 15 as a bottom surface and outside the visual field region.

  By arranging the transmission type diffusion plates 12A and 12B in this way, the degree of freedom of arrangement of the transmission type diffusion plates 12A and 12B is improved even when the aperture angle of the objective lens 15 is large. Therefore, the directivity of light irradiated to the object 3 from the transmissive diffusion plates 12A and 12B can be sufficiently lowered, and a sufficient halation suppression effect can be obtained.

  In the image capturing apparatus 1 of the present embodiment, the light shielding unit 13A is provided between the transmission type diffusion plate 12A and the objective lens 15, and the light shielding unit 13B is provided between the transmission type diffusion plate 12B and the objective lens 15. It has been. Shading part 13A. 13B is arranged in a conical region having the observed point 4 as a vertex and the entrance pupil of the objective lens 15 as a bottom surface, and outside the visual field region defined by the objective lens 15 and the opening 16a of the slit 16. Shading part 13A. 13B can block stray light from the transmissive diffusion plates 12A and 12B and the object 3 toward the objective lens 15. Thereby, measurement accuracy can be improved.

  Furthermore, in the image capturing device 1 of the present embodiment, the light shielding unit 14A is provided between the irradiation unit 11A and the transmission type diffusion plate 12A, and the light shielding unit 14B is provided between the irradiation unit 11B and the transmission type diffusion plate 12B. It has been. The light shielding unit 14A blocks light that travels straight to the observation point 4 from the light output from the illumination unit 11A. The light shielding unit 14B blocks light that travels straight to the observation point 4 from the light output from the illumination unit 11B. Thereby, the directivity of the light scattered from the transmissive diffusion plates 12A and 12B and applied to the object 3 can be further reduced. Moreover, when the wavelength of the light output from the illumination units 11A and 11B is in the range from the visible range to the near infrared range, thermal damage to the object 3 can be reduced.

  Next, an example using the image photographing device 1 of the present embodiment is compared with a comparative example. In both Examples and Comparative Examples, a biological sample having irregularities on the surface was used as the object 3. In the comparative example, the transmissive diffusion plates 12A and 12B are disposed outside the conical region having the observed point 4 as the apex and the entrance pupil of the objective lens 15 as the bottom surface. In the comparative example, the light shielding plates 13A and 13B were not provided.

  FIG. 2 is a diagram illustrating a two-dimensional image acquired in the embodiment. FIG. 3 is a diagram showing the intensity distribution on the broken line in FIG. FIG. 4 is a diagram illustrating a two-dimensional image acquired in the comparative example. FIG. 5 is a diagram showing the intensity distribution on the broken line in FIG. As can be seen by comparing these figures, in the example using the image capturing apparatus 1 of the present embodiment, halation is remarkably suppressed, and the accuracy of the spectral image data is improved.

DESCRIPTION OF SYMBOLS 1 ... Image pick-up device, 2 ... Sample stand, 3 ... Object, 4 ... Observation point, 11A, 11B ... Illumination part, 12A, 12B ... Transmission-type diffuser plate, 13A, 13B ... 1st light-shielding part, 14A, 14B ... 2nd light-shielding part, 15 ... Objective lens, 16 ... Slit, 17 ... Spectroscope, 18 ... Imaging part.

Claims (3)

An illumination unit that outputs light;
A transmissive diffusion plate for diffusing the light output from the illumination unit and irradiating the object;
An objective lens for inputting light that is diffused and reflected by the object among the light irradiated on the object;
A slit that defines a linear field of view in the first direction together with the objective lens;
A spectroscope that splits light that has passed through the slit in a second direction perpendicular to the first direction;
An imaging unit that receives light split by the spectroscope and acquires a two-dimensional image;
With
The transmissive diffusion plate does not penetrate into the visual field area, and is at least in a conical area having the observed point of the object in the visual field area as a vertex and the objective lens as a bottom surface and outside the visual field area. It is arranged so that a part exists,
An image photographing apparatus characterized by that.   The apparatus further comprises a first light-shielding portion provided between the transmissive diffusion plate and the objective lens within the conical region and outside the visual field region, and blocking light directed toward the objective lens. Item 2. The image photographing device according to Item 1. The image capturing apparatus according to claim 1, further comprising a second light-shielding unit that blocks light that travels straight from the illumination unit to the observation point.