JP3069284U - Photodetector - Google Patents

Abstract

(57) [Problem] To provide an improved photosensitive device having a high effect of eliminating interference of scattered light generated when a work beam hits a light receiving element. The present invention comprises at least one light source, at least one capstan, and at least one light receiving element, wherein the light source is installed close to the capstan and projects light on the capstan, An element is provided at a position close to the capstan so as to face the peripheral side of the capstan, and the light receiving element includes a light receiving chip for receiving a work beam reflected by the capstan, and the work beam is connected to the light receiving element. A light detecting device, wherein two or four slopes, or a conical surface or a concave surface are provided around a light receiving chip on a light receiving surface of a light receiving element in order to remove interference when projected on And

Description

[Detailed description of the invention]

[0001]

[Technical field to which the invention belongs]

 The present invention relates to a kind of light receiving means, and more particularly, to a light receiving means which is not affected by scattered light.

[0002]

[Prior art]

 FIG. 1, FIG. 2 and FIG. 3 show a known photodetector, which includes at least one light source 1, one light receiving element 3, and one capstan 2. The light source 1 is arranged close to the capstan 2, so that the light emitted from the light source 1 is projected on the capstan 2. The light receiving element 3 includes a light receiving chip 31 which is placed at a position facing the side circumference of the capstan 2 and receives the work beam 11 reflected from the capstan 2. Further, two or four slopes 32 are arranged around the light receiving chip 31, and when the work beam 11 is projected on the light receiving surface of the light receiving element 3, the interference phenomenon formed by the proximity light is eliminated and the encoder is reliably provided to the encoder. To get the right signal.

[0003]

[Problems to be solved by the invention]

 An object of the present invention is to provide an improved photodetector having a high effect of eliminating interference of light from a light source when a working beam impinges on a light receiving element.

[0004]

[Means for Solving the Problems]

 The invention of claim 1 comprises at least one light source, at least one capstan, and at least one light receiving element, wherein the light source is located proximate to the capstan and projects light onto the capstan, wherein the light receiving element The light receiving element is provided at a position close to the capstan so as to face the peripheral side of the capstan, the light receiving element includes a light receiving chip for receiving a work beam reflected on the capstan, and the work beam is Light detection, characterized in that two or four slopes, or a conical surface or a concave surface are provided around the light receiving chip on the light receiving surface of the light receiving element in order to eliminate interference when the light is projected onto the light receiving element. Equipment. The invention of claim 2 is characterized in that, in the photodetector, the photodetector includes a cover that covers a light receiving surface of the light receiving chip and has an opening corresponding to a front of the light receiving chip. Photodetector. The invention according to claim 3 is the photodetector according to claim 1, wherein the light receiving surface of the light receiving element is coated with a light absorbing material or a reflecting material by printing or bonding.

[0005]

[Embodiment of the invention]

 The photodetector of the present invention provides a conical surface, two inclined surfaces or four inclined surfaces on the light receiving surface of the light receiving chip. Furthermore, a light absorbing material is applied to the slope to eliminate the interference of reflected light.

[0006]

【Example】

 See FIG. 3, A in FIG. 4, and FIG. The light detection device of the present invention includes at least one light source 1, at least one capstan 2, and at least one light receiving element 3. More specifically, the light source 1 is installed close to the capstan 2 and projects light on the capstan 2. The capstan 2 is mounted on a rotatable shaft 21 and driven by a driving means 20 (ball means).

Further, the shaft 21 contacts the ball 20, and the shaft 21 rotates when the ball 20 rolls. Therefore, the capstan 2 also rotates jointly. Further, a plurality of transparent parts 22 are arranged around the capstan 2, and an opaque part 23 is arranged between each two transparent parts 22.

The light receiving element 3 is made of a transparent material and is disposed at a position facing the side circumference of the capstan 2. Two adjacent light receiving chips 31 are mounted in the light receiving element 3 to receive the working beam transmitted through the transparent part 22. The light projected on the surface of the light receiving element 3 is reflected by two or four slopes 32 provided around the chip 31. As shown in FIG. 4B, the slope 32 is further coated with a light absorbing or reflective material to prevent scattering of light by the slope. As shown in FIG. 4B, the light reflected on the slope does not affect the detection of light by the light receiving chip 31.

The light emitted from the light source 1 is cut by the transparent portion and the opaque portion of the capstan 2 to form a working beam 11. As shown in FIG. 5, the working beam 11 is received by the light receiving chip 31 and is (0,0), (0,1), (1,1), (1) by the rectifier circuit of the capstan 2 which rotates continuously. , 0).

FIG. 6 shows an embodiment of the light receiving element. According to this embodiment, a concave conical surface 33 is provided around the light receiving chip 31. The working beam projected on the light receiving element 3 is received by the light receiving chip 31 or reflected by the conical surface 33. Therefore, the light receiving chip 31 is not affected by the scattered light.

FIG. 7 shows another embodiment of the light receiving element. According to this embodiment, the light receiving element 3 is covered by a cover 4 made of a reflective or light absorbing material.

Further, an opening 41 is formed at a position corresponding to the front of the light receiving chip 31 of the cover 4. The cover 4 has a function of removing scattered light.

Further, in the embodiment shown in FIG. 8A, an opaque cover 4 having two openings 41 covers the light receiving element 3 having no slope. The opening 41 is provided in front of the corresponding light receiving chip 31.

In the embodiment shown in FIG. 8B, an opaque cover 4 having two openings 41 covers the light receiving element 3 having a slope. The opening 41 is provided in front of the corresponding light receiving chip 31.

In the embodiment shown in FIG. 9A, the light receiving surface of the light receiving element 3 is coated with a light absorbing material 34 or a reflecting material by printing or bonding, so that the scattered light is absorbed or reflected by the light absorbing material 34 or the reflecting material. Thus, the detection function of the light receiving element 3 is not affected.

In the embodiment shown in FIG. 9B, the light receiving surface of the light receiving element 3 having a conical surface is coated with a light absorbing material 34 or a reflecting material by printing or bonding, so that the scattered light is absorbed by the light absorbing material 34 or The light is not absorbed or reflected by the reflecting material and does not affect the detection function of the light receiving element 3.

The above is a description of the embodiment of the present invention, and is not intended to limit the scope of the present invention, but to modify or modify details that can be easily made based on the present invention. Any design matter that can achieve the effects shall belong to the claims of the present invention.

[0018]

[Effect of the invention]

 The photodetector of the present invention has a high effect of eliminating the interference of scattered light generated when the work beam hits the light receiving element, and reduces the influence of the scattered light on the light detection function of the light receiving chip of the light receiving element. The accuracy of the function can be improved.

[Brief description of the drawings]

FIG. 1 is a perspective view of a known photosensitive unit.

FIG. 2 is a partially enlarged view (A) of FIG. 1 and a working beam is FIG.
FIG. 8B is a beam path display diagram (B) when the light is projected on the light receiving surface of the light receiving element of FIG.

FIG. 3 is a perspective view of the photosensitive device of the present invention.

FIG. 4 is a partially enlarged view (A) of FIG. 4 and a working beam is FIG.
FIG. 7B is a beam path display diagram (B) when the light is projected on the light-collecting surface of the light receiving element of FIG.

FIG. 5 is a diagram showing four signals (0, 0), (0, 1), (1, 1), and (1, 0) generated by rotation of the capstan of the present invention.

FIG. 6 is a perspective view of an embodiment of the light receiving element of the present invention.

FIG. 7 is a sectional view of an embodiment of the light receiving element of FIG. 6;

FIG. 8 is a cross-sectional view of two embodiments of the light receiving element of the present invention.

FIG. 9 is a perspective view of two embodiments of the light receiving element of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Light source 11 Working beam 2 Capstan 20 Driving means 22 Transparent part 23 Opaque part 3 Light receiving element 31 Light receiving chip 32 Slope 33 Conical surface 34 Light absorbing material 4 Cover

Claims (3)

[Utility model registration claims] 1. A light source comprising: at least one light source; at least one capstan; and at least one light receiving element, wherein the light source is disposed in proximity to the capstan and projects light onto the capstan, and the light receiving element is The light receiving element is provided at a position close to the capstan so as to face the peripheral side of the capstan, and the light receiving element includes a light receiving chip for receiving a work beam reflected on the capstan, and the work beam is projected on the light receiving element. A photodetector, wherein two or four inclined surfaces, or a conical surface or a concave surface are provided around a light receiving chip on a light receiving surface of the light receiving element in order to remove interference when the light is detected. 2. The light according to claim 1, wherein the light detecting device includes a cover that covers a light receiving surface of the light receiving chip and has an opening corresponding to a front of the light receiving chip. Detection device. 3. The light detecting device according to claim 1, wherein the light receiving surface of the light receiving element is coated with a light absorbing material or a reflecting material by printing or bonding.