JP2006067034A - Visual sensor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a visual sensor for preventing such failure as the deterioration of the contrast of an image from being generated. <P>SOLUTION: This visual sensor is provided with an optical member 11 constituted of solid translucent materials having an incident face 17a to which peripheral rays of light L are made incident, a reflection layer 15 formed in a hyperboloid-shaped recess 17b of the optical member 11 for reflecting the peripheral rays of light L and an image pickup element 13 for imaging the peripheral rays of light L reflected on the reflection layer 15. This visual sensor is provided with a light guiding part 18 integrally formed with the optical member 11 for guiding the peripheral rays of light L and a case body 12 arranged in the image pickup element 13. An extended section 12c constituted by extending a portion of the case body 12 is connected to the light guiding part 18, and an outer peripheral face 18a of the light guiding part 18 is covered by the extended section 12c. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a visual sensor that reflects a wide range of ambient light with a reflecting member and picks up an image by an imaging means such as a CCD (Charge Coupled Device).

Conventionally, various omnidirectional vision sensors have been proposed, and for example, disclosed in Patent Document 1 and Patent Document 2. Such an omnidirectional visual sensor reflects ambient light with a hyperboloidal reflection mirror, and images the surroundings with an imaging device such as a CCD.
JP-A-10-160463 JP 2000-128031 A

  The image sensor is mounted on a circuit board, and the circuit board on which the image sensor is mounted is disposed on the bottom wall portion of the case body. A cylindrical cylindrical body made of a translucent material is provided on the side wall of the case body, and a reflection mirror is disposed inside the cylindrical body. A lid is disposed in the upper opening of the cylindrical body, and the reflection mirror is fixed to the lid. The reflecting mirror has a hyperboloid shape, and is arranged so as to hang from the lid with the apex of the hyperboloid shape facing downward.

  However, the omnidirectional visual sensor described above has a problem that it cannot be provided at low cost because of the large number of parts. That is, the cylindrical body made of a light-transmitting material has no optical effect, and therefore the number of parts can be reduced if the cylindrical body can be eliminated. Therefore, the applicant of the present application has proposed a visual sensor that can be manufactured at low cost with a small number of parts, as Japanese Patent Application No. 2003-339306 and Japanese Patent Application No. 2003-339309.

  As shown in FIG. 5, the visual sensor 1 is an optical made of a faithful translucent material having a reflective layer 3 that reflects ambient light provided on an incident surface 2a on which ambient light is incident and a hyperboloid-shaped concave portion 2b. It has a member 2 and imaging means 4 such as a CCD camera that images the ambient light reflected by the reflective layer 3. The imaging means 4 is mounted on the circuit board 5 and is disposed in the case body 6 together with the circuit board 5. The case body 6 has a bottom wall portion 6a and a side wall portion 6b. A circuit board 6 is disposed and fixed on the bottom wall portion 6a, and an opening end portion of the side wall portion 6b is provided with an optical member 2. The lower end (end of the straight part) of the light guide part 2c formed to extend in the vertical direction from the end of the incident surface 2a is joined. The light guide 2c guides the ambient light L reflected by the reflective layer 3 to the imaging means 4 through the exit surface 2d.

  However, for the visual sensor 1 having the optical member 2 having the solid structure having the light guide portion 2c, unnecessary light is easily incident from the outer peripheral surface of the light guide portion 2c, and the contrast of the image is lowered. Had problems.

  Therefore, the present invention has been made in view of this problem, and further improves the visual sensor proposed by the applicant of the present application, and provides a visual sensor that does not reduce the contrast of an image.

  The present invention provides an optical member made of a solid light-transmitting material having an incident surface on which ambient light is incident, and a concave portion of the optical member, as in the visual sensor according to claim 1, and the ambient light A visual sensor comprising: a reflecting member that reflects light; and an imaging unit that images the ambient light reflected by the reflecting member, and is provided integrally with the optical member and guides the ambient light to the imaging unit. A light guide part and a case body for disposing the imaging means, and joining the extension part formed by extending a part of the case body and the light guide part, and by the extension part It covers at least a part of the light guide.

  A visual sensor according to a second aspect is the visual sensor according to the first aspect, wherein the light guide portion and the extending portion are joined via a sealant.

  According to a third aspect of the present invention, in the visual sensor according to the first aspect, the light guide portion and the extending portion are provided with a rotation preventing mechanism.

  With respect to a visual sensor that reflects a wide range of ambient light with a reflecting member and picks up an image with an image pickup means, unnecessary light can be prevented from entering from the light guide, so that it does not cause problems such as reducing the contrast of the image and is desired. Images can be obtained.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

  1 and 2, the visual sensor 10 includes an optical member 11, a case body 12, an imaging element 13 (imaging means), a circuit board 14, a reflective layer 15 (reflective member), and a lid body 16. It is configured.

  As shown in FIG. 3, the optical member 11 is made of a solid translucent resin (for example, polycarbonate), and has a substantially spherical base portion 17 and a substantially cylindrical light guide portion 18. . The base portion 17 of the optical member 11 includes a spherical incident surface 17a on which the ambient light L is incident, and a hyperboloid concave portion 17b. The incident surface 17a of the optical member 11 is a spherical surface whose center is located above the hyperboloid focal point f1 in the concave portion 17b. In this specification, the “spherical surface” is at least a part of the surface of the sphere, not the entire surface of the sphere.

  A reflective layer 15 made of a metal film such as aluminum (Al) or chromium (Cr) is formed in the concave portion 17b of the optical member 11. The reflective layer 15 is formed by coating the concave portion 17b by a method such as vapor deposition. Moreover, the hole 17c is provided in the top part of the concave part 17b of a hyperboloid shape. The hole portion 17c has an elongated shape along the X-axis direction of the hyperboloid shape. Since the ambient light M that causes the ghost image is reflected by the peripheral surface of the hole 11d, the ambient light M is suppressed from reaching the imaging element 13.

  The light guide portion 18 of the optical member 11 guides the light reflected by the reflection layer 15 to the image pickup device 13 including a CCD camera or the like, and has a substantially cylindrical shape. The light guide 18 has a cylindrical outer peripheral surface 18 a and an exit surface 18 b that faces the image sensor 13. As shown in FIG. 3, a D-cut portion 18 c is formed on a part of the outer peripheral surface 18 a of the light guide portion 18. The light exiting surface 18b of the light guide 18 refracts the light toward the focal point f2 of the hyperboloid to be paired toward the image sensor 13 and forms an image with the image sensor 13.

  As shown in FIG. 4, the case body 12 has a substantially cylindrical shape corresponding to the light guide portion 18 of the optical member 11 and is made of a non-translucent resin material. The case body 12 has a bottom wall portion 12a and a cylindrical side wall portion 12b. A circuit board 14 on which the image sensor 13 is mounted is disposed and fixed on the bottom wall portion 12a. In addition, an extended portion 12c that covers the light guide portion 18 of the optical member 11 is formed in the extended portion of the side wall portion 12b. In addition, a part of the inner wall 12c in the extending part 12c (side wall part 12b) has a part of the inner surface of the cylinder as a flat surface, and a positioning part corresponding to the D-cut part 18c formed in the light guide part 18 of the optical member 11. 12d is formed.

  The D-cut portion 18c of the optical member 11 and the positioning portion 12d of the case body 12 constitute a positioning mechanism that determines the arrangement position of the optical member 11 with respect to the case body 12, and the periphery of the optical member 11 with respect to the case body 12 It also constitutes a stop mechanism. In addition, as a bonding condition between the optical member 11 and the case body 12, a sealing agent is used for the case body 12 and the optical element in order to ensure the sealing of the storage space S of the case body 12 that stores the imaging element 13 and the circuit board 14. A sealing agent such as an ultraviolet curable adhesive or silicone rubber is disposed between the joint portion with the member 11, that is, between the outer peripheral surface 18a of the light guide portion 18 and the inner wall 12c of the extending portion 12c.

  The ambient light L is incident on the inside of the base portion 17 from the incident surface 17a, is reflected by the reflective layer 15, and is guided to the image sensor 13 by the light guide portion 18. The visual sensor 10 has a visual field C1 from 0 ° to an elevation angle of about 30 ° and a visual field C2 from 0 ° to a depression angle of 30 °. The image data output from the image sensor 13 is output to an image processing unit (not shown) and is used for recognition of obstacles around the visual sensor 10.

  The lid body 16 is made of a resin material, and is disposed at the opening end portion 17d of the optical member 11 (base portion 17) so as to cover the concave portion 17b in which the reflective layer 15 is formed. The lid body 16 is disposed on the opening end portion 17d with a good sealing property through an adhesive so as to prevent entry of water, dust, or the like into the concave portion 17b.

  The visual sensor 10 is provided in an optical member 11 made of a solid translucent material having an incident surface 17a on which ambient light L is incident, and a hyperboloid-shaped concave portion 17b of the optical member 11, and reflects the ambient light L. A visual sensor that includes a reflecting layer 15 to be imaged and an image sensor 13 that images the ambient light L reflected by the reflective layer 15, and is a light guide that is provided integrally with the optical member 11 and guides the ambient light L to the image sensor 13. A portion 18 and a case body 12 for disposing the image pickup device 13. The extension portion 12 c formed by extending a part of the case body 12 and the light guide portion 18 are joined, and the extension portion 12 c Thus, the outer peripheral surface 18a of the light guide 18 is covered.

  Therefore, since the ambient light M irradiated to the light guide part 18 is interrupted by the extending part 12c of the case body 12, there is no problem of reducing the contrast of the image.

  In addition, the light guide 18 and the extended portion 12c are provided with a positioning mechanism and a detent mechanism composed of a D-cut portion 18c and a positioning portion 12d, and the light guide 18 and the extended portion 12c Since it is connected via the sealing agent, the assembling property of the visual sensor 10 can be improved, and the anti-rotation mechanism is configured, so that one of the optical member 11 and the case body 12 rotates. The occurrence of breakage of the sealing agent that occurs at the time is eliminated, and the sealing property of the storage space S in the case body 12 can be improved.

  The reflective layer 15 is not limited to being formed in the hyperboloid-shaped concave portion 17b, and may be formed in, for example, a conical concave portion. Moreover, although the reflective member of each embodiment was the reflective film 15 coated on the concave portion 17b, for example, a reflective member made of a thin metal plate may be insert-molded into the optical member 11. The image pickup means is the image pickup element 13 such as a CCD, but may be a CMOS camera, for example.

  Further, in the embodiment of the present invention, in the rotation preventing mechanism between the optical member 11 and the case body 12, the optical member 11 is provided with the D-cut portion 18c, and the case body 12 is provided with the positioning portion 12d, whereby the rotation preventing mechanism. However, the rotating stop mechanism of the present invention is not limited to the above-described embodiment. For example, the outer peripheral surface of the light guide portion 18 of the optical member 11 is formed into a polygonal shape, and the case body 12 is configured. The inner wall 12 of the extended portion 12c may be a polygonal positioning portion that is aligned with the outer peripheral surface of the light guide portion 18, and these may be used as a detent mechanism.

  Further, in the embodiment of the present invention, the entire outer peripheral surface 18a of the light guide 18 is provided by the extending part 12c, but half of the light guide 18 is covered by the incident condition of the ambient light M. Also good.

It is sectional drawing which shows the visual sensor of embodiment of this invention. It is explanatory drawing which shows the optical path of embodiment same as the above. It is a figure which shows the optical member of embodiment same as the above. It is a figure which shows the case body of embodiment same as the above. It is sectional drawing which shows the conventional visual sensor.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Visual sensor 11 Optical member 12 Case body 12a Bottom wall part 12b Side wall part 12c Extension part 12d Positioning part 13 Image pick-up element (imaging means)
15 Reflective layer (reflective member)
17 base portion 17a incident surface 17b recess 18 light guide portion 18a outer peripheral surface 18b exit surface 18c D cut portion S storage space

Claims (3)

An optical member made of a solid translucent material having an incident surface on which ambient light is incident, a reflective member that is provided in a concave portion of the optical member and reflects the ambient light, and the ambient light reflected by the reflective member A visual sensor comprising imaging means for imaging light,
An extension formed by extending a part of the case body, the light guide unit integrally provided on the optical member and guiding the ambient light to the imaging unit; and a case body for disposing the imaging unit. A visual sensor characterized by joining a light guide part and the light guide part and covering at least a part of the light guide part by the extending part.   The visual sensor according to claim 1, wherein the light guide portion and the extending portion are joined via a sealant.   The visual sensor according to claim 1, wherein the light guide portion and the extending portion are provided with a rotation prevention mechanism.

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