JP2021120994A - Light detection unit - Google Patents

Abstract

To allow a light waveguide of a light detection unit to extend through a thin space or to be set in a thin space.SOLUTION: A light detection unit 400 includes: light waveguides 410 and 420 in the shape of a sheet wide in a horizontal direction, the light waveguides having cores and clads provided in layers in a vertical direction; and a connector unit 500 removably attached to a light projection connector or a light receiving connector of an optical sensor.SELECTED DRAWING: Figure 4

Description

The present invention relates to a photodetector unit connected to an optical sensor having a light emitting element and a light receiving element.

Conventionally, a light emitting element that generates detection light to irradiate the detection region and a light receiving element that receives the detection light from the detection region are provided, and the light receiving signal generated by the light receiving element is compared with a threshold value and the comparison result is obtained. There is known an optical detection unit configured to output a signal regarding the presence or absence of an article (see, for example, Patent Document 1).

When performing light detection using this type of photodetector unit, a photodetector unit having a light emitting side optical fiber connected to a light emitting element and a light receiving side optical fiber connected to the light receiving element is generally used. Used for. The optical fiber constituting the optical detection unit of Patent Document 1 is composed of a bundled optical fiber in which a plurality of optical fiber wires are bundled.

Japanese Patent No. 4177178

By the way, in the case of a bundled optical fiber in which a plurality of optical fiber wires are bundled like the optical fiber of Patent Document 1, the outer diameter of the optical fiber is the wire diameter of the optical fiber wire constituting the optical fiber due to its structure. It was inevitable that it would be several times more than.

However, there are cases where the optical fiber of the photodetector unit is passed through a place where the space between the parts is narrow and only a thin space can be secured, or it is desired to install the optical fiber in such a thin space. In these cases, the bundled optical fiber of Patent Document 1 has a large outer diameter and is difficult to deal with.

The present invention has been made in view of this point, and an object of the present invention is to allow an optical waveguide of a photodetector unit to be passed through a thin space or to be installed in a thin space.

In order to achieve the above object, in the first aspect of the present disclosure, a light emitting element that projects detection light toward a detection region, a light receiving element that receives detection light from the detection region, and the light emitting element. A detection signal that compares the light-emitting connection for optical coupling, the light-receiving connection for optical coupling to the light-receiving element, the light-receiving signal generated by the light-receiving element, and the threshold value, and shows a comparison result. It is premised on an optical detection unit connected to an optical sensor having a signal generation unit for generating light.

The photodetection unit has an optical waveguide and a connector portion. The optical waveguide guides light between the first end portion and the second end portion to form a wide sheet in the horizontal direction, and has a core and a clad surrounding the core, and the core and the clad are formed. It is provided in a layered manner in the vertical direction, and the first end portion is connected to the light projecting connection portion or the light receiving connecting portion so as to be photocoupled to the light emitting element or the light receiving element of the optical sensor, and the second end portion is connected to the light emitting connection portion or the light receiving connecting portion. A member whose end is a light projecting end or a light receiving end, which projects light into the detection area or receives light from the detection area. The first end of the optical waveguide is connected to the connector, and the first end of the optical waveguide is directly or indirectly connected to the light projection connection or the light reception connection of the optical sensor. It is a member that is optically connected to and detachably attached to the light projecting connection portion or the light receiving connecting portion.

According to this configuration, the optical waveguide has a wide sheet shape in the horizontal direction and has a core and a clad provided in a layered manner in the vertical direction. It becomes possible to secure the amount of light. The first end of the optical waveguide can be connected to the light projecting connection or the light receiving connection of the optical sensor by the connector. Since the connector part is detachably attached to the light projection connection part or the light reception connection part, it is possible to connect the light detection unit to the optical sensor or replace the light detection unit as necessary. It will be easier.

In the second aspect of the present disclosure, the connector portion may have a convex portion inserted into the light projecting connection portion or the light receiving connecting portion.

According to this configuration, the optical waveguide can be easily connected to the light projecting connection or the light receiving connection by inserting the convex portion of the connector into the light projecting connection or the light receiving connection. can. The convex portion may be provided on both the light emitting side and the light receiving side, and by integrating the convex portion on the light emitting side and the convex portion on the light receiving side, the connection work becomes even easier.

The optical sensor may be provided with a clamping mechanism for clamping the convex portion. The clamp mechanism is unclamped, the convex part is inserted into the light emitting connection part or the light receiving connection part, and after the insertion, the clamping mechanism is clamped so that the convex part does not separate from the optical sensor. be able to.

In the third aspect of the present disclosure, the first end portion of the optical waveguide is exposed on the tip surface of the convex portion, and the convex portion is formed on the light projecting connection portion or the light receiving connection portion. The first end portion may be positioned at the center position of the light emitting surface of the light emitting element or the light receiving surface of the light receiving element in the inserted state.

According to this configuration, since the first end portion of the optical waveguide is exposed on the tip surface of the convex portion, the optical waveguide can be made into a light emitting element by inserting the convex portion into the light emitting connection portion or the light receiving connection portion. Alternatively, it can be optical-coupled to the light receiving element. At this time, since the first end portion of the optical waveguide is positioned at the center position of the light emitting surface of the light emitting element or the light receiving surface of the light receiving element, it is possible to suppress a decrease in the amount of light at the connecting portion.

In the fourth aspect of the present disclosure, the optical waveguide is connected to the light projection connection portion of the optical sensor, and the second end portion serves as a light projection end for projecting light to the detection region. An optical waveguide which is connected to the light receiving connection portion of the optical sensor and whose second end portion serves as a light receiving end and receives light from a detection region may be included. Further, the connector portion is connected to the first end portion of the light projecting optical waveguide, and the light emitting side optical fiber is optically coupled to the light projecting connection portion so as to be inserted and removed, and the light receiving optical waveguide. It may be a member that integrally bundles a light receiving side optical fiber that is connected to the first end portion and is photocoupled to the light receiving connecting portion so as to be insertable and removable.

According to this configuration, the first end of the light projecting optical waveguide can be connected to the light projecting connection via the light projecting side optical fiber, and the first end of the light receiving optical wave guide can be connected. , It can be connected to the light receiving connection portion via the light receiving side optical fiber. At this time, since the light emitting side optical fiber and the light receiving side optical fiber are integrally bundled by the connector, the light emitting side optical fiber and the light receiving side optical fiber can be easily inserted and removed. Further, since the light emitting side optical fiber and the light receiving side optical fiber serve as relay members, the shape of the optical path end surface of the light emitting optical waveguide and the light receiving optical waveguide is that of the light emitting connection part and the light receiving connection part of the optical sensor. Even if the shape is different, it can be easily dealt with. Further, even if the distance between the light emitting side optical fiber and the light receiving side optical fiber is determined by the request of the optical sensor side, the distance between the light emitting optical waveguide and the light receiving optical waveguide prior to the connector can be freely set. It can be set and can be adjusted to the detection target and detection method.

In the fifth aspect of the present disclosure, the light emitting side optical fiber and the light receiving side optical fiber may be a bundled optical fiber in which a plurality of optical fiber wires are bundled.

In the sixth aspect of the present disclosure, on the connection side of the light projecting side optical fiber with the light projecting optical wave guide, a plurality of fiber wires constituting the light projecting side optical fiber form the light projecting optical wave guide. They may be arranged side by side in the width direction of.

That is, when the light projecting side optical fiber is configured by the bundled optical fiber, the end face shape is close to a circle, whereas the light projecting optical waveguide is wide in the horizontal direction, and the connection portion between the two is connected. The shape difference becomes large, and as a result, the light loss may increase. In this configuration, since a plurality of fiber lines constituting the light projecting side optical fiber are arranged side by side in the width direction of the light projecting optical wave guide, the connection between the light projecting side optical fiber and the light projecting optical wave guide is provided. The difference in shape of the portion is reduced, and the light loss can be reduced.

On the connection side of the light receiving side optical fiber with the light receiving optical waveguide, a plurality of fiber wires constituting the light receiving side optical fiber may be arranged side by side in the width direction of the light receiving optical waveguide.

In the seventh aspect of the present disclosure, a rod lens long in the width direction of the light projecting optical wave guide may be provided between the light projecting side optical fiber and the light projecting optical wave guide.

A transparent elastic material long in the width direction of the light receiving optical waveguide may be provided or a transparent adhesive may be provided between the light receiving side optical fiber and the light receiving optical waveguide.

In the eighth aspect of the present disclosure, an optical type having a light projecting hole optically coupled to the light projecting element in the housing and a light receiving hole optically coupled to the light receiving element in the housing. It is possible to assume an optical detection unit that is detachably connected to the sensor.

In the optical detection unit, the end on the sensor side is optically coupled to the light projection hole, the detection end is arranged so as to project the detection light toward the detection region, and the core through which the light passes and the clad surrounding the core are arranged. The sheet-shaped first optical waveguide and the sensor side end are optically coupled to the light receiving hole, and the detection end is arranged so as to receive the detection light from the detection region. A sheet-shaped second optical waveguide having a clad surrounding the first optical waveguide, a connector portion for integrating the first optical waveguide and the second optical waveguide, and a sensor-side end of the first optical waveguide provided in the connector portion. A projecting side projection having a substantially circular cross section that surrounds the periphery of the portion and having substantially the same size as the projection hole, and a sensor-side end portion of the second optical waveguide provided on the connector portion. It has a substantially circular cross section that surrounds the periphery, and has a light receiving side convex portion having substantially the same size as the light receiving hole.

That is, since the first optical waveguide and the second optical waveguide have a sheet shape, it is possible to secure the amount of light of the optical waveguide while thinning the optical waveguide. When connecting the photodetector unit to the optical sensor, the projection side convex portion integrated with the connector may be inserted into the projection hole of the optical sensor, and the workability at the time of connection is good. When the projection side convex portion is connected, the projection side convex portion has substantially the same size as the projection hole, so that the projection side convex portion is positioned in the projection hole. Similarly, the light receiving side convex portion is also positioned. Thereby, the light loss can be reduced.

In the ninth aspect of the present disclosure, the outer diameter of the projection side convex portion can be made larger than the thickness dimension of the first optical waveguide.

The light emitting side convex portion and the light receiving side convex portion may be an optical fiber.

The light emitting hole and the light receiving hole of the optical sensor are arranged vertically with respect to the housing, and the light emitting path and the light receiving path of the optical waveguide are arranged in the horizontal direction of a sheet. A twisted portion may be provided between the detection region of the optical waveguide and the connection hole. The twisted portion may be an optical fiber portion.

An indicator light for extracting light passing through the core of the optical waveguide to the outside may be provided between the first end portion and the second end portion of the optical waveguide on the optical waveguide on the light emitting side or the light receiving side. ..

The light-emitting connection portion and the light-receiving connection portion are circular holes, and the portion of the connector portion that is detachably attached to the light-emitting connection portion or the light-receiving connection portion is The core of the optical waveguide may be a portion arranged in a sheet shape.

The connector portion may be a portion that grips the optical waveguide on the light emitting side and the light receiving side. The connector may have a through hole for fixing.

The portion where the optical fiber and the optical waveguide are optically coupled may be inside the connector. The optical waveguide may be provided with a hole for fixing.

As described above, since the optical waveguide in which the core and the clad are provided in layers in the vertical direction form a wide sheet in the horizontal direction, the optical waveguide can be made into a thin space while ensuring the amount of light of the optical waveguide. It can be passed through or installed in a thin space. Since the connector portion is detachably attached to the light projection connection portion or the light reception connection portion, the light detection unit can be easily connected and the light detection unit can be easily replaced.

FIG. 1 is a perspective view showing a usage state of an optical sensor to which a photodetector unit according to an embodiment of the present invention is connected. FIG. 2 is a block diagram of the optical sensor. FIG. 3 is a vertical cross-sectional perspective view for explaining the element holder and the member held by the element holder. FIG. 4 is a plan view showing a state in which the light guide portion and the connector portion of the light detection unit are separated. FIG. 5 is a perspective view in which the upper covering member of the light guide portion of the light detection unit is omitted. FIG. 6 is a sectional view taken along line VI-VI in FIG. FIG. 7 is an enlarged plan view showing the vicinity of the end of the optical waveguide. FIG. 8A is an enlarged cross-sectional view of an optical waveguide having a plurality of cores. FIG. 8B is an enlarged cross-sectional view of an optical waveguide having one core. FIG. 9 is an enlarged view of the tip end side of the light guide portion of the photodetector unit shown in FIG. FIG. 10 is a cross-sectional view taken along line XX of FIG. 4 showing a detection state of the work. FIG. 11 is a plan view showing an example in which the photodetector unit is fixed to the mounting member by the fixing member. FIG. 12 is a vertical cross-sectional view showing an example in which the photodetector unit is fixed to the mounting member by the fixing member. FIG. 13 is a plan view showing an example in which the photodetector unit is fixed to the mounting member by the fixing plate. FIG. 14 is a vertical cross-sectional view showing an example in which the photodetector unit is fixed to the mounting member by a fixing plate. FIG. 15 is a diagram showing an example in which the photodetector unit is fixed to the mounting member by the hook-shaped member. FIG. 16 is a plan view showing an example in which the photodetector unit is directly fixed to the mounting member with screws. FIG. 17 is a vertical cross-sectional view showing an example in which the photodetector unit is directly fixed to the mounting member with screws. FIG. 18 is a perspective view showing an example in which a covering member is provided on a fixed portion of the light detection unit. FIG. 19 is a perspective view showing an example in which a covering member is provided on a fixed portion of the light detection unit and both sides of the covering member are fixed in the width direction. FIG. 20 is a perspective view showing an example in which a covering member is provided on a fixed portion of the light detection unit and the tip end side of the covering member is fixed. FIG. 21 is a perspective view showing an example in which a covering member is provided on a fixed portion of the photodetection unit, and a portion between the tip end side of the covering member and the light emitting optical wave guide and the light receiving optical wave guide is fixed. FIG. 22 is a vertical cross-sectional view showing an example of fixing the photodetector unit using a washer. FIG. 23A is a vertical cross-sectional view of a portion where the optical waveguides are connected to each other. FIG. 23B is a plan view of a portion where the optical waveguides are connected to each other. FIG. 24 is a perspective view showing a configuration example in which a light projecting optical wave guide and a light receiving optical wave guide are formed on a single member to realize limited reflection. FIG. 25 is a perspective view showing a configuration example in which a reflector made of a separate member is provided at the tip of the light projecting optical wave guide and the light receiving optical wave guide to realize limited reflection. FIG. 26 is a plan view of a photodetection unit showing an example of an optical waveguide pattern in consideration of reducing light loss. FIG. 27A is a diagram showing an example in which the light emitting mirror surface is provided on the tip surface of the optical waveguide for light projection. FIG. 27B is a diagram showing an example in which the direction of the tip surface of the optical waveguide for light projection is set by the direction setting member. FIG. 28 is a plan view of a photodetection unit showing an example of an optical waveguide pattern in which the outer size is prioritized. FIG. 29 is a perspective view showing an example in which a plurality of optical fibers are arranged in a horizontal direction in an optical waveguide for light projection and an optical waveguide for light reception. FIG. 30 is a plan view showing an example of limited reflection that emits light from the tip of the optical waveguide. FIG. 31 is a plan view showing another example of limited reflection that emits light from the tip of the optical waveguide. FIG. 32 is a plan view showing an example of limited reflection that emits light from the side surface of the optical waveguide. FIG. 33 is a plan view showing another example of limited reflection that emits light from the side surface of the optical waveguide. FIG. 34 is a plan view showing an example of using as a multi-point reflection type photodetection unit. FIG. 35 is a diagram showing an example in which the tip of the optical waveguide is bent. FIG. 36A is a diagram showing an example in which an optical waveguide and a mirror member are combined. FIG. 36B is a diagram showing another example of combining the optical waveguide and the mirror member. FIG. 37 is a diagram showing an example of installing a regression reflector. FIG. 38A is a diagram showing an example of a transmission type photodetection unit when the light-emitting optical wave guide and the light-receiving optical wave guide extend in the same direction. FIG. 38B is a diagram showing an example of a transmission type photodetection unit in the case where the light emitting optical wave guide and the light receiving optical wave guide extend in opposite directions. FIG. 39 is a diagram showing an example of a transmissive light detection unit when the tip of the optical waveguide for light projection and the tip of the optical waveguide for light reception face each other. FIG. 40 is a diagram showing an example of a transmissive light detection unit when detecting a work in the light detection unit. FIG. 41 is a diagram showing an example of a transmissive photodetector unit in which a large number of optical paths are formed. FIG. 42 is a plan view of the connector portion according to the first example. FIG. 43 is a side view of the connector portion according to the first example. FIG. 44 is a cross-sectional view taken along the line AA in FIG. 43. FIG. 45 is a cross-sectional view taken along the line BB in FIG. 42. FIG. 46 is a cross-sectional view taken along the line CC in FIG. 43. FIG. 47 is a view of the connector portion according to the first example as viewed from the tip side. FIG. 48 is a perspective view of the connector portion according to the first example as viewed from the side where the pressing member is arranged. FIG. 49 is a perspective view of the connector portion according to the second example. FIG. 50 is a plan view of the connector portion according to the third example. FIG. 51 is a view of the connector portion according to the third example as viewed from the tip side. FIG. 52 is a diagram showing an example including a pre-installation adapter. FIG. 53 is a diagram showing an example in which the light emitting hole and the light receiving hole of the optical sensor have a slit shape. FIG. 54 is a perspective view showing a connector portion according to the fourth example. FIG. 55A is a perspective view showing the structure of the first example of the relay portion as viewed from the front side. FIG. 55B is a perspective view showing the structure of the first example of the relay portion as viewed from the back side. FIG. 55C is a perspective view showing the structure of the first example of the relay portion. FIG. 56A is a cross-sectional view showing a first example of the relay portion. FIG. 56B is a plan view showing a first example of the relay portion. FIG. 57 is a plan view showing a second example of the relay portion. FIG. 58 is a cross-sectional view showing a second example of the relay portion. FIG. 59 is a plan view showing a third example of the relay portion.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. It should be noted that the following description of the preferred embodiment is essentially merely an example and is not intended to limit the present invention, its application or its use.

FIG. 1 is a perspective view showing a usage state of the optical sensor 1 to which the photodetector unit 400 according to the embodiment of the present invention is connected. The optical detection device 300 is composed of the light detection unit 400 and the optical sensor 1. FIG. 1 is a perspective view of the optical detection device 300 viewed from diagonally above, and shows an example in which four optical detection devices 300 are installed next to each other on a DIN rail 2, and one of them is an optical device. The formula detection device 300 is shown with the upper lid 4 open.

One of the plurality of optical detection devices 300 installed adjacent to the DIN rail 2 is a master unit, and the other is a slave unit. For example, when the projection of the master unit is completed, the master unit supplies a signal for starting the projection to the first slave unit, and the projection of the first slave unit is executed. When the projection of the first slave unit is completed, the signal for starting the projection is supplied from the first slave unit to the second slave unit, and the projection of the second slave unit is executed. Hereinafter, the projection of the third and fourth slave units is sequentially started.

The usage example shown in FIG. 1 is an example, and the optical detection device 300 can be used by only one unit, or the optical detection device 300 can be used by being fixed to a member other than the DIN rail 2. can.

(Configuration of optical sensor 1)
As shown in the block diagram of the optical detection device 300 in FIG. 2, the optical sensor 1 constituting the optical detection device 300 includes a light emitting unit 102 and a light receiving unit 202. The light projecting unit 102 outputs a predetermined pulsed light to the photodetection unit 400. The light emitting element 104 of the light projecting unit 102 is driven by an oscillating pulse supplied from the light projecting power supply control circuit 302 to emit pulsed light. On the other hand, the light received by the light receiving unit 202 is photoelectrically converted by the light receiving element 204 and sent to the control unit 308 via the light receiving element amplifier circuit 206, the amplifier circuit 304, and the A / D converter 306. As a result, detection synchronized with the pulsed light is performed, and the detection signal is further converted into a DC signal or the like, and then output as an ON / OFF signal indicating the detection result from the I / O circuit 360 constituting the interface unit. ..

The optical sensor 1 includes a light projecting circuit 106 for driving the light emitting element 104. The light emitting element 104 is a member for projecting the detected light toward the detection region, and a typical example of the light emitting element 104 is a light emitting diode (LED), but the light emitting element 104 is not limited to this.

The light projecting circuit 106 includes a light projecting APC circuit 108 and a light receiving element 110 for monitoring such as a monitor PD. The floodlight APC circuit 108 controls the output of the light emitting element 104, that is, the amount of light emitted to a predetermined value. The monitor light receiving element 110 of the light projecting unit 102 is connected to the monitor signal amplification circuit 114, and transmits the light receiving amount to the LED light emitting amount monitor circuit 312 via the monitor line. The LED light emission amount monitor circuit 312 supplies the light reception amount signal converted into a digital signal to the control unit 308 via the A / D converter 314. The control unit 308 controls the floodlight power supply control circuit 302 so that the light emission amount becomes a predetermined value based on the light emission amount detected by the monitor light receiving element 110, and adjusts the current amount of the light projection APC circuit 108. Feedback control for driving the light emitting element 104 is performed.

The optical sensor 1 includes a light receiving circuit 208 for driving the light receiving element 204. The light receiving element 204 is a member that receives the detected light from the detection region, and is connected to the light receiving element amplifier circuit 206. The amount of light received by the light receiving element 204 is amplified by the light receiving element amplifier circuit 206, sent to the amplifier circuit 304, and then amplified by the controller amplifier circuit 304. The analog signal amplified by the controller amplifier circuit 304 is converted into a digital signal via the A / D converter 306 and input to the signal generation unit 308a of the control unit 308. The signal generation unit 308a detects the amount of light received by the light receiving element (photodiode PD) 204, compares the light received signal generated by the light receiving element 204 with a predetermined threshold value, and generates a detection signal indicating a comparison result. .. The detection signal generated by the signal generation unit 308a is finally output from the I / O circuit 360.

The control unit 308 includes a storage unit 326 for storing various set values, a display circuit 328 for displaying information on the optical sensor 1 side, an operation button 6 which is a user interface for receiving set value adjustments, and the like. A switch input circuit 330 to which 8 (shown in FIG. 1) is connected, an I / O circuit 360 for input / output to / from the outside, and the like are connected, and these circuits are driven by a controller power supply circuit 332.

The control unit 308 can be composed of, for example, a central processing unit, an IC such as an FPGA or an ASIC. Each of the various circuits (reference numerals 108, 114, 206, 214, 302, 304, 306, 312, 314, 320, 328, 330, 332, 360) may be composed of an IC, or may be used in various circuits. It may be composed of one IC, or the control unit 308 and various circuits may be composed of one IC.

As shown in FIG. 1, a display unit 334 is provided on the upper surface of the housing 10 of the optical sensor 1. In this description, the side located above when in use as shown in FIG. 1 is referred to as "upper", but this is only defined for convenience of explanation, and which side of the optical sensor 1 is. It may be installed so that it faces up.

The display unit 334 is composed of, for example, an organic EL display, a flat display, or the like, and is controlled by the display circuit 328 shown in FIG. The display unit 334 may be a segment display as shown in FIG. The detected value (light receiving amount), the threshold value, and the like are displayed using the display unit 334. The display unit 334 may be configured by a 7-segment display arranged side by side.

As shown in FIG. 1, on the upper surface of the housing 10 of the optical sensor 1, operation buttons such as an up / down button 6, a mode button 8, and a set button 9 are arranged adjacent to the display unit 334. The optical sensor 1 has two channels for output, but is not limited to this. Reference numeral 16 indicates an operation indicator lamp for displaying the current output or detection state, reference numeral 16a indicates an operation indicator lamp of the first channel, and reference numeral 16b indicates an operation indicator lamp of the second channel.

A non-conversion display mode in which the detection value (light reception amount) and the threshold value are displayed as they are by operating the buttons 6, 8, 9, etc., and the display detection value converted by the display conversion rate or the display conversion formula. It is possible to switch between the (display light receiving amount) and the conversion display mode for displaying the display threshold value, and to set the sensitivity and the threshold value. Since the display target, display mode, display display switching operation, and display mode switching of the optical sensor 1 are described in detail in JP-A-2006-351380 and JP-A-2019-61885, this JP The description thereof will be omitted by reference to JP-A-2006-351380 and JP-A-2019-61885.

An element holder 368 as shown in FIG. 3 is provided inside the housing 10 of the optical sensor 1. The element holder 368 is a member that holds the light emitting element 104 and the light receiving element 204. A light emitting member 370 and a light receiving member 372 are housed in the element holder 368. The light projecting member 370 is a member that substantially constitutes the above-mentioned light projecting unit 102, and includes a light emitting element 104, a light receiving element 110 for a monitor, and a reflector 380. The light receiving member 372 is a member that substantially constitutes the above-mentioned light receiving unit 202, and includes a light receiving element 204 and an LED 212 as a light display and light emitting element. In this embodiment, the light emitting element 104 and the light receiving element 204 are arranged in the vertical direction. Specifically, the light emitting element 104 is located on the light receiving element 204, but the light receiving element 204 is located on the light emitting element 104. The light emitting element 104 and the light receiving element 204 may be arranged in the left-right direction (horizontal direction).

The element holder 368 has a light emitting hole 376 and a light receiving hole 378 to which the light detection unit 400 is connected. The light emitting hole 376 and the light receiving hole 378 are formed of through holes having a circular cross section, and are formed so as to penetrate the element holder 368. The light projecting hole 376 constitutes a light projecting connection portion for optical coupling to the light emitting element 104 by directly or indirectly connecting the light projecting optical waveguide 410 (shown in FIG. 4) included in the light detection unit 400. doing. Further, the light receiving hole 378 constitutes a light receiving connection portion for optical coupling to the light receiving element 204 by directly or indirectly connecting the light receiving optical waveguide 420 included in the light detection unit 400. The specific configurations of the light-flooding optical waveguide 410 and the light-receiving optical waveguide 420 will be described later.

That is, the end portions of the light emitting hole 376 and the light receiving hole 378 have a first insertion port 376a and a second insertion port 378a that open to the outer surface of the element holder 368. A light emitting element 104 is arranged behind the light projecting hole 376. The light emitting element 104 is mounted on the light projection mounting substrate 382. The position of the light emitting element 104 is set so that the center of the light emitting surface of the light emitting element 104 is located on the extension line of the center line of the light projecting hole 376.

A light receiving element 204 is arranged behind the light receiving hole 378. The light receiving element 204 is mounted on the light receiving mounting substrate 384. The position of the light receiving element 204 is set so that the center of the light receiving surface of the light receiving element 204 is located on the extension line of the center line of the light receiving hole 378. The space in which the light emitting element 104 is arranged and the space in which the light receiving element 204 is arranged are optically isolated. A glass plate 374, which is a translucent member, is interposed between the light receiving element 204 and the end portion on the back side of the light receiving hole 378.

(Clamp mechanism)
The optical sensor 1 has a clamping mechanism for clamping the photodetector unit 400 in a connected state. The clamp mechanism is provided inside the housing 10, and sandwiches a portion (details will be described later) inserted into the light emitting hole 376 and the light receiving hole 378 of the photodetection unit 400 in the radial direction of the holes 376 and 378. It is configured to be possible. When the portion of the light detection unit 400 inserted into the light emitting hole 376 and the light receiving hole 378 is clamped by the clamping mechanism, the inserted portion is prevented from coming out of the light emitting hole 376 and the light receiving hole 378. It is supposed to be done.

On the other hand, as shown in FIG. 1, an operation lever 7 for operating the clamp mechanism from the outside is provided on the outside of the housing 10. By moving the operating lever 7 in a predetermined direction, the clamping mechanism can be brought into the clamped state. By moving the operating lever 7 in the direction opposite to the predetermined direction, the clamping mechanism can be unclamped.

The configuration of the clamping mechanism and the operating lever 7 is not limited to the above-described configuration, as long as the portion inserted into the light emitting hole 376 and the light receiving hole 378 of the light detection unit 400 can be clamped. good.

(Overall configuration of photodetector unit 400)
As an example shown in FIG. 4, the light detection unit 400 includes a light guide unit 401 and a connector unit 500, and is a unit capable of detecting a work WK (shown in FIG. 10) by limited reflection. The connector portion 500 will be described later.

Here, the sensor that detects the work WK by limited reflection limits the detection area of the object and irradiates the detection area in order to detect whether or not the work WK exists at a predetermined position. This is a type of sensor that receives the reflected light reflected by the work WK at the light receiving unit.

Although details will be described later, the photodetector unit 400 is provided with first to fourth insertion holes 402 to 405 through which a fixing member such as a screw is inserted.

As shown in FIGS. 5 and 6, the light guide unit 401 includes an optical waveguide 410 for light projection, an optical waveguide 420 for light reception, a light extraction member 430, an upper covering member 440, and a lower covering member 450. I have. The distal end side and the proximal end side of the photodetector unit 400 are defined as shown in FIGS. 4 and 5. The base end side of the photodetector unit 400 is the side connected to the optical sensor 1 and the side on which the connector portion 500 is provided. The tip side of the photodetection unit 400 is the side that detects the work WK (shown in FIG. 9 and the like).

As shown in FIG. 5, the optical waveguide 410 for light projection has an elongated strip shape so as to guide light between the base end portion (first end portion) and the tip end portion (second end portion) of the light detection unit 400. It is formed. The base end is the sensor side end, and the tip is the detection end. As shown in FIG. 8A, the optical waveguide 410 for light projection has a horizontally wide sheet shape in which the horizontal dimension (width dimension W) is set longer than the vertical dimension (thickness dimension t). There is. The main surfaces of the optical waveguide 410 for light projection are an upper surface and a lower surface. The side surface of the optical waveguide 410 for light projection is a surface located on both sides in the width direction. The optical waveguide 410 for light projection can be used in a posture in which the horizontal direction shown in FIG. 6 faces the vertical direction, or can be used in a posture in which the horizontal direction shown in FIG. 6 is inclined.

As shown in FIG. 8A, the light projecting optical waveguide 410 has a plurality of cores 411 arranged horizontally spaced apart from each other, and a clad 412 surrounding the cores 411. By changing the refractive indexes of the core 411 and the clad 412, the light incident on the core 411 travels by causing total internal reflection at the interface between the core 411 and the clad 412. There is almost no loss of light at this time.

The number of cores 411 can be set to any number and is not limited to the number shown in the figure. By providing a plurality of cores 411, it is possible to increase the amount of light without increasing the thickness of the optical waveguide 410 for light projection, which is preferable. The cross-sectional shape of the core 411 is not particularly limited, but may be, for example, a rectangular shape. The clad 412 has an upper portion 412a that covers the core 411 from above, a lower portion 412b that covers the core 411 from below, and an intermediate portion 412c that is interposed between the cores 411 and the cores 411 that are arranged in the horizontal direction. There is. The upper portion 412a of the clad 412, the core 411, and the lower portion 412b of the clad 412 are provided in layers in the vertical direction and integrated.

The intermediate portion 412c of the clad 412 extends from the upper portion 412a to the lower portion 412b. The structure is such that the upper portion 412a and the lower portion 412b are connected by the intermediate portion 412c. In the example shown in FIG. 8A, the cores 411 located at both ends of the optical waveguide 410 for light projection in the width direction are not covered by the clad 412 and are exposed. The core 411 located at may be covered with a clad 412.

As shown in FIG. 7, which is an enlarged plan view of the vicinity of the tip of the optical waveguide 410 for light projection, the intermediate portion 412c of the clad 412 does not have to reach the tip of the optical waveguide 410 for light projection. good.

As shown in FIG. 8B, the number of cores 411 may be one. When there is one core 411, it can be formed so as to have a long cross section in the width direction of the optical waveguide 410 for light projection. In this case, the intermediate portion 412c of the clad 412 disappears, and the clad 412 is composed of an upper portion 412a and a lower portion 412b. Both sides of the core 411 in the width direction may be exposed or covered with a clad 412.

The optical waveguide 410 for light projection is a so-called polymer optical light guide path. Examples of the material of the optical waveguide 410 for light projection include, but are not limited to, resins such as acrylic, epoxy, siloxane, silicone, polyimide, polysilane, polynorbornene, and fluororesin, and are desired. A material that satisfies the optical properties and physical properties can be appropriately used. Only one kind of the above-mentioned material may be used, or any plurality of kinds may be mixed and used. In addition, additives for improving optical properties and physical properties can be added to the above materials. By forming the light projecting optical wave guide 410 with the above-mentioned resin, the light projecting optical wave guide 410 has flexibility and flexibility, and also has a predetermined heat resistance.

The method for forming the core 411 of the optical waveguide 410 for light projection can be selected according to the material. For example, it can be selected from the physical etching method (RIE method), stamping method (molding method), photobleaching method (UV conversion method), direct light exposure method (UV curing method), etc., but is limited to these. It is not something that can be done.

As shown in FIG. 6, the light receiving optical waveguide 420 can be configured in the same manner as the light projecting optical waveguide 410, and has a core 421 and a clad 422. The optical waveguide 420 for light reception and the optical waveguide 410 for light projection may be exactly the same, or may have different dimensions or the like. The light-flooding optical waveguide 410 and the light-receiving optical waveguide 420 are arranged at intervals in the width direction. The distance between the light-flooding optical waveguide 410 and the light-receiving optical waveguide 420 is not particularly limited, but can be set to 5 mm or more in consideration of screwing described later, for example.

The light-flooding optical waveguide 410 and the light-receiving optical waveguide 420 are covered on the outside of the light-emitting optical waveguide 410 with an upper coating member 413 and a lower coating member 414 as reinforcing materials, and are reinforced on the outside of the light-receiving optical waveguide 420. It is covered with the upper covering member 423 and the lower covering member 424 as materials, and further covered with the upper covering member 440 and the lower covering member 450 having light opacity. The upper covering member 413 and the lower covering member 414, and the upper covering member 423 and the lower covering member 424 are the first covering members. The upper covering member 440 and the lower covering member 450 are the second covering members. Therefore, the photodetector unit 400 includes a coating member having a laminated structure.

That is, the lower surface of the clad 412 of the light emitting optical waveguide 410 is covered with the lower covering member 414, and the lower surface of the clad 421 of the light receiving optical waveguide 420 is covered with the lower covering member 424. The 414 and the lower covering member 424 are covered by the lower covering member 450. Further, the upper surface of the clad 412 of the light emitting optical waveguide 410 is covered with the upper covering member 413, and the upper surface of the clad 421 of the light receiving optical waveguide 420 is covered with the upper covering member 423, and these upper covering members 413 and the upper side are covered. The covering member 423 is covered with an upper covering member 440. As shown in FIGS. 4 and 5, the upper covering member 440 and the lower covering member 450 are formed in a sheet shape extending from the tip end portion of the light projecting optical waveguide 410 and the light receiving optical waveguide 420 to the proximal end side. .. The base end side of the light projecting optical wave guide 410 and the light receiving optical wave guide 420 protrudes from the base end side of the upper covering member 440 and the lower covering member 450, and is covered by the upper covering member 440 and the lower covering member 450. Not. The portion of the light projecting optical waveguide 410 and the light receiving optical waveguide 420 that is not covered by the covering members 440 and 450 is a portion that is inserted and removed from the optical sensor 1.

Hereinafter, the description of the upper covering member 413, the lower covering member 414, the upper covering member 423, and the lower covering member 424 will be omitted because they are provided on the upper and lower surfaces of the optical waveguide 410 or the optical waveguide 420. That is, the upper covering member 413 and the lower covering member 414 can be members that form a part of the optical waveguide 410, and in this case, the upper covering member 413 and the lower covering member 414 are included and referred to as an optical waveguide 410. be able to. For example, when explaining "to make a hole in the optical waveguide 410", it means to make a hole in the upper covering member 413 and the lower covering member 414 on the upper and lower surfaces of the optical waveguide 410, but the explanation is complicated. Therefore, it is omitted. Similarly, the upper covering member 423 and the lower covering member 424 can be members that form a part of the optical waveguide 420, and in this case, the upper covering member 423 and the lower covering member 424 are included in the optical waveguide 420. Can be called. The upper covering member 413, the lower covering member 414, the upper covering member 423, and the lower covering member 424 may be provided, only a part of them may be provided, or all of them may not be provided. Needless to say, it's good. Further, the upper covering member 413 and the lower covering member 414 may be treated as a member different from the optical waveguide 410, and the upper covering member 423 and the lower covering member 424 may be treated as a member different from the optical waveguide 420. You may handle it.

The upper covering member 440 and the lower covering member 450 have a light-shielding property of blocking light emitted from the light emitting element 104. The upper covering member 440 and the lower covering member 450 do not have to block 100% of the light emitted from the light emitting element 104, and may have, for example, 90% or more of light blocking property. The upper covering member 440 and the lower covering member 450 may have a light-shielding property according to the wavelength of the light emitted from the light emitting element 104 and a damping effect for attenuating the light. The colors of the upper covering member 440 and the lower covering member 450 may be other than black in appearance, for example, dark blue. The resin material constituting the upper covering member 440 and the lower covering member 450 can be colored by printing.

The light-flooding optical waveguide 410 and the light-receiving optical waveguide 420 are made of a material that is transparent to the light propagating therein. The upper covering member 413, the lower covering member 414, the upper covering member 423, and the lower covering member 424 have a role of reinforcing the optical waveguide 410 for light projection and the optical waveguide 420 for light reception, and at the interface with them. It is made of an opaque material to reflect. Polyimide can be mentioned as an example of the material. As described above, the upper covering member 440 and the lower covering member 450 provided on the outer side have a light-shielding property, and the upper covering member 413, the lower covering member 414, the upper covering member 423, and the lower covering member Processing such as coloring is performed so as to have a higher light-shielding property than 424. The upper covering member 440 and the lower covering member 450 and the upper covering member 413, the lower covering member 414, the upper covering member 423, and the lower covering member 424 may be made of polyimide, which is the same material, and the upper covering member may be used. A difference in light-shielding property may be provided by printing black on the 440 and the lower covering member 450. It should be noted that there are two horizontal locations between the light receiving optical waveguide 420 and the upper covering member 440 and the lower covering member 450 in FIG. 6, and the light projecting optical waveguide 410, the upper covering member 440 and the lower covering member 450. The two horizontal parts between and are the parts that contain air. A laminate consisting of an optical waveguide 410 for floodlight, an upper coating member 413, and a lower coating member 414 and a laminate consisting of an optical waveguide 420 for light reception, an upper coating member 423, and a lower coating member 424 are combined with an upper coating member 440 and a lower side. Air may enter when covering with the covering member 450. As a result, light leakage can be reduced by the difference in refractive index between the optical waveguide 410 for light projection and the optical waveguide 420 for light reception and air.

An adhesive layer and an adhesive layer are provided on the back surface of the upper covering member 440. The upper covering member 440 is adhered or adhered to the upper surface of the clad 412 of the light emitting optical waveguide 410 and the upper surface of the clad 421 of the light receiving optical waveguide 420. As a result, the upper covering member 440 is integrally configured with the light-flooding optical waveguide 410 and the light-receiving optical waveguide 420.

An adhesive layer and an adhesive layer are also provided on the back surface of the lower covering member 450. The lower covering member 450 is adhered or adhered to the lower surface of the clad 412 of the light emitting optical waveguide 410 and the lower surface of the clad 421 of the light receiving optical waveguide 420. As a result, the lower covering member 450 is integrally configured with the light-flooding optical waveguide 410 and the light-receiving optical waveguide 420.

The upper covering member 440 and the lower covering member 450 are adhered to or adhered to each other on both sides in the width direction. As a result, light leakage from both sides in the width direction can be suppressed. Further, the upper covering member 440 and the lower covering member 450 are also adhered to or adhered to each other between the light emitting optical waveguide 410 and the light receiving optical waveguide 420. As a result, the optical waveguide 410 for light projection and the optical waveguide 420 for light reception can be optically isolated.

The upper covering member 440 and the lower covering member 450 can be made of, for example, a flexible resin tape, a resin sheet, a resin film, or the like. Examples of the resin material that can be used include, but are not limited to, polyimide, and a resin that has flexibility and flexibility and has strength that does not break during fixing, which will be described later. Any material may be used. When the upper coating member 440 and the lower coating member 450 are colored, they may be colored with a pigment or a dye.

Further, the optical waveguide 410 for light projection and the optical waveguide 420 for light reception may be covered with one covering member without being separated into the upper covering member 440 and the lower covering member 450. Further, the covering member may have a bag shape, and the shape thereof is not particularly limited. The upper covering member 440 and the lower covering member 450 are formed so as not to cover the light emitting end which is the tip of the light emitting optical waveguide 410 and the light receiving end which is the tip of the light receiving optical waveguide 420. , The light extraction member 430, the light projecting end of the light projecting optical wave guide 410, and the light receiving end of the light receiving optical wave guide 420 can be photocoupled.

On the upper covering member 440 and the lower covering member 450, for example, characters, symbols, marks, etc. indicating the manufacturer name, product number, model, etc. of the photodetection unit 400 can be described. By making the upper covering member 440 and the lower covering member 450 a dark color such as black and making the characters, symbols, marks, etc. a light color such as white, the characters, symbols, marks, etc. become more conspicuous. By writing characters, symbols, marks, etc. only on the upper surface, for example, the user can easily determine which is the upper surface. For example, characters, symbols, marks, etc. may be described on the upper covering member 440 or the lower covering member 450 as a direction display unit indicating the directions of up and down, front and back, and the like.

By providing the upper covering member 440 and the lower covering member 450, it is possible to suppress light leakage from the light emitting optical waveguide 410 and the light receiving optical waveguide 420 when the photodetection unit 400 is bent and installed. .. Further, by integrating the upper covering member 440 and the lower covering member 450 with the light projecting optical wave guide 410 and the light receiving optical wave guide 420, the light projecting optical wave guide 410 and the light receiving optical wave guide 420 are reinforced to increase the strength. Can be enhanced. For example, when the photodetection unit 400 is bent and installed, the bending of the light-flooding optical waveguide 410 and the light-receiving optical waveguide 420 can be suppressed by the upper covering member 440 and the lower covering member 450. On the other hand, since the upper covering member 440, the lower covering member 450, the light emitting optical waveguide 410 and the light receiving optical waveguide 420 have flexibility, for example, the light detection unit 400 may be bent when bypassing an obstacle. , Can be twisted and bent, increasing the degree of freedom of handling. Even in this way, the leakage of light from the optical waveguide 410 for light projection and the optical waveguide 420 for light reception can be suppressed, so that the detection performance is not adversely affected.

Further, in the present embodiment, the optical waveguide 410 for light projection and the optical waveguide 420 for light reception are characterized in that they are sheet-like and thin, so that the photodetection unit 400 can be arranged in a thin space. On the other hand, if the light-flooding optical waveguide 410 and the light-receiving optical waveguide 420 are thin, they may be easily bent and entangled during handling, resulting in poor handleability. However, the upper covering member 440 and the lower covering member 450 may be deteriorated. By providing the above, the bending of the optical waveguide 410 for light projection and the optical waveguide 420 for light reception is appropriately suppressed, and the entanglement is less likely to occur, and the handleability is improved.

The rigidity of the resin material constituting the upper coating member 440 and the lower coating member 450 can be set higher than the rigidity of the resin material constituting the light-flooding optical waveguide 410 and the light-receiving optical waveguide 420. As a result, the reinforcing effect of the upper covering member 440 and the lower covering member 450 is further enhanced. Further, the resin material constituting the upper coating member 440 and the lower coating member 450 can be made less slippery than the resin material constituting the light-flooding optical waveguide 410 and the light-receiving optical waveguide 420. This makes the light detection unit 400 less slippery when the light detection unit 400 is installed.

Further, as shown in FIGS. 8A and 6, the core 411 is partially exposed on the horizontal end face of the optical waveguide 410 for light projection. This is to strengthen the end face. For example, when the clad constituting the optical waveguide 410 for light projection is manufactured by modifying the core, the core 411 has a higher strength than the clad 412. Therefore, by exposing the core 411, the strength on the end face side can be increased.

Further, as shown in FIG. 7, the end face on the distal end side of the optical waveguide 410 for light projection is the core 411. Further, the horizontal end faces (left and right ends on the paper surface of FIG. 7) are also cores 411. This is because the core 411 has higher strength than the clad 412, so that the portion exposed to the outside is the core 411 instead of the clad 412.

As shown in FIG. 9, the light extraction member 430 is arranged at the tip of the light detection unit 400, and is provided from the tip of the light projecting optical waveguide 410 to the tip of the light receiving optical waveguide 420. It is formed in a shape. The thickness of the light extraction member 430 is set to be about the same as the thickness of the optical waveguide 410 for light projection and the optical waveguide 420 for light reception. As shown in FIG. 9, the left and right sides of the photodetector unit 400 are defined, but this is for convenience of explanation only, and does not limit the actual usage state.

The light extraction member 430 can be made of a material having the same light guide property as the material of the core 411 of the optical waveguide 410 for light projection. As shown in FIG. 10, the light extraction member 430 is composed of a single core 430a. The light extraction member 430 may have a clad similar to the clad 412 of the optical waveguide 410 for light projection. The lower surface of the light extraction member 430 is adhered or adhered to the lower coating member 450, and the upper surface of the light extraction member 430 is adhered or adhered to the upper coating member 440. As a result, the relative positions of the light extraction member 430 and the light projecting optical waveguide 410 and the light receiving optical waveguide 420 can be prevented from shifting, and the light extraction member 430 can be placed on the upper covering member 440 and the lower side. It can be covered by the covering member 450.

As shown in FIG. 9, the right side of the light extraction member 430 is abutted against the tip of the optical waveguide 410 for light projection. As a result, the light extraction member 430 and the plurality of cores 411 of the light projection optical waveguide 410 are optically coupled, so that the light traveling through the cores 411 of the light projection optical waveguide 410 is incident on the right side portion of the light extraction member 430. do. A transparent elastic material or a transparent adhesive may be interposed between the light extraction member 430 and the tip of the optical waveguide 410 for light projection.

A right inclined surface 431 is formed at the tip on the right side of the light extraction member 430. The right inclined surface 431 is a reflecting surface, and the traveling direction of the light incident on the right side of the light extraction member 430 is converted to the left by the right inclined surface 431. The inclination angle of the right side inclined surface 431 with respect to the longitudinal direction of the optical waveguide 410 for light projection is set so that the light incident on the right side of the light extraction member 430 is directed to the left side.

On the right side of the upper surface of the light extraction member 430, a light emission mirror surface 432 as a light emission portion is provided. The light emitting mirror surface 432 is formed of a surface inclined at a predetermined angle with respect to the upper surface of the light extraction member 430, and the light incident on the right side of the light extraction member 430 and converted to the left side by the right inclined surface 431. The direction is emitted from the main surface side (upper surface side) of the light projecting optical waveguide 410 toward the detection region R (shown in FIG. 10) by the light emitting mirror surface 432. The tip of the optical waveguide 410 for light projection serves as a light projecting end, and light is projected onto the detection region R via the light extraction member 430. The light emitting mirror surface 432 can be obtained by, for example, laser processing. A vapor-deposited film on which a metal is vapor-deposited may be formed on the light emitting mirror surface 432 in order to improve the reflectance.

The incident and exit angles of light can be set to about 0.2, which makes it possible to realize a small projection spot and a light receiving field of view without adding a lens or the like. The optical paths shown in each figure may be reversed. That is, the light emitting side in each figure may be the light receiving side, and the light receiving side may be the light receiving side. The distance between the light detection unit 400 and the work WK is not particularly limited, but can be, for example, about 0 mm to 3 mm.

The detection area R is an area in which the work WK to be detected is arranged, and is a planned arrangement area of the work WK. In this form, it is located above the light extraction member 430. The light emission angle can be changed depending on the angle of the light emission mirror surface 432.

The left side of the light extraction member 430 is abutted against the tip of the light receiving optical waveguide 420. As a result, the light extraction member 430 and the light receiving optical waveguide 420 are photocoupled, so that the light traveling on the left side portion of the light extraction member 430 is incident on the core 421 of the light receiving optical waveguide 420. A transparent elastic material or a transparent adhesive may be interposed between the light extraction member 430 and the tip of the light receiving optical waveguide 420.

As shown in FIG. 10, when the work WK is arranged in the detection region R, the light irradiated to the work WK is reflected and travels downward, and the light corresponds to the portion where the light reaches. A light incident mirror surface 433 as a light incident portion is provided on the upper surface of the take-out member 430. The light incident mirror surface 433 is composed of a surface inclined at a predetermined angle with respect to the upper surface of the light extraction member 430, and the inclination angle of the light incident mirror surface 433 is set so that the incident light travels to the left. There is.

As shown in FIG. 9, a left inclined surface 434 is formed at the tip on the left side of the light extraction member 430. The left inclined surface 434 is a reflecting surface, and the traveling direction of the light incident on the light extraction member 430 from the light incident mirror surface 433 and traveling to the left side is converted by the left inclined surface 434 and incident on the light receiving optical waveguide 420. The inclination angle of the left side inclined surface 434 with respect to the longitudinal direction of the light receiving optical waveguide 420 is set so that the light incident on the left side of the light extraction member 430 is directed to the base end side of the photodetection unit 400. The tip of the light-receiving optical waveguide 420 is a light-receiving end that receives light from the detection region R via the light extraction member 430. The light emitting mirror surface 432 and the light incident mirror surface 433 are not covered by the upper covering member 440 and are exposed.

A plurality of cores 411 and 421 are arranged in the optical waveguide 410 for light projection and the optical waveguide 420 for light reception, but the light extraction member 430 has a single core. When having a plurality of cores, it is difficult to align the cores with each other at the time of photocoupling, but it is easy to photocoupling the plurality of cores to a core having a larger cross-sectional area. Therefore, by abutting the optical waveguide 410 for light projection and the optical waveguide 420 for light reception with the light extraction member 430, light coupling can be performed while suppressing light loss, and the assembling property is good.

(Fixed structure of photodetector unit 400)
As shown in FIGS. 11 and 12, when the photodetector unit 400 is installed, it can be fixed to, for example, the mounting member 600 to be mounted. The mounting member 600 may be, for example, a member forming a part of various devices, a surface plate, or the like. In the examples shown in FIGS. 11 and 12, the photodetector unit 400 is fixed to the surface of the mounting member 600 by a fixing member 601 made of an adhesive, an adhesive, double-sided tape, or the like. At this time, the lower surface of the lower covering member 450 becomes the installation surface, and becomes the surface fixed to the attachment member 600. When the installation surface is horizontal, the light-emitting optical waveguide 410 and the light-receiving optical waveguide 420 are arranged horizontally. As shown in FIG. 3, the light-emitting hole 376 of the optical sensor 1 and the light-receiving optical waveguide 420 are used. Since the holes 378 are arranged in the vertical direction, it is necessary to handle the optical waveguide 410 for light projection and the optical waveguide 420 for light reception so as to be twisted in the middle. Also in this case, since the light-emitting optical waveguide 410 and the light-receiving optical waveguide 420 coated with the upper covering member 440 and the lower covering member 450 are sheet-shaped and have predetermined flexibility and flexibility. , Can be easily handled.

A wide portion 400a, which is wider than the base end side, is provided on the tip end side of the photodetection unit 400. By fixing the wide portion 400a to the mounting member 600 by the fixing member 601, the area of the fixed portion can be increased.

13 and 14 show an example in which the photodetector unit 400 is screwed to the mounting member 600 using the fixing plate 602. The fixing plate 602 is made of, for example, a hard resin or a metal material, and is formed so as to extend along the upper surface of the mounting member 600. The fixed plate 602 is formed to be wider than the width on the tip end side of the photodetector unit 400. Insertion holes (not shown) through which the screws 603 are inserted are formed on both sides of the fixing plate 602 in the width direction. This insertion hole is positioned on the outer side of the tip side of the photodetection unit 400, and the screw 603 is inserted into the insertion hole in a state where the fixing plate 602 is overlapped on the upper surface of the light detection unit 400 on the tip side, and the mounting member. When screwed into 600, the fixing plate 602 and the mounting member 600 can be fixed by sandwiching the tip end side of the photodetector unit 400 in the thickness direction. The fixing plate 602 is arranged so as not to cover the light emitting mirror surface 432 and the light incident mirror surface 433. A nail, stapler, or the like can be used instead of the screw 603.

FIG. 15 shows an example in which the photodetector unit 400 is fixed to the mounting member 600 by the hook-shaped member 604. FIG. 15 is a vertical cross section orthogonal to the longitudinal direction of the photodetector unit 400. The hook-shaped member 604 is formed so as to surround the mounting member 600, and is made of, for example, a hard resin or a metal material. The hook-shaped member 604 has a pair of legs 604a. By engaging the hook-shaped member 604 with the mounting member 600 from above the tip end side of the light detection unit 400, the hook-shaped member 604 and the mounting member 600 sandwich and fix the tip end side of the light detection unit 400 in the thickness direction. be able to. The hook-shaped member 604 is arranged so as not to cover the light emitting mirror surface 432 and the light incident mirror surface 433.

16 and 17 show an example of fixing the photodetector unit 400 by directly screwing it to the mounting member 600. The photodetector unit 400 is provided with first to fourth insertion holes 402 to 405 (shown in FIG. 4) through which screws 605 used as fixing members used when installing the light detection unit 600 are inserted. The first to fourth insertion holes 402 to 405 penetrate the upper covering member 440 and the lower covering member 450 in the vertical direction. That is, the upper covering member 440 and the lower covering member 450 have a portion covering the cladding 412 and 422 between the light emitting end and the light receiving end of the light emitting optical waveguide 410 and the light receiving optical waveguide 420. The portion covering the clad 412 and 422 between the light emitting end and the light receiving end is a portion fixed to the mounting member 600.

The first insertion hole 402 is located on the most proximal side, and the fourth insertion hole 405 is located on the most distal end side. The second insertion hole 403 and the third insertion hole 404 are located between the first insertion hole 402 and the fourth insertion hole 405, and the second insertion hole 403 is closer to the base end side than the third insertion hole 404. It's getting closer. The third insertion hole 404 is close to the fourth insertion hole 405. The first to fourth insertion holes 402 to 405 may be formed of elongated holes. The first to fourth insertion holes 402 to 405 are located in the portion of the covering members 440 and 450 corresponding between the light-emitting optical waveguide 410 and the light-receiving optical waveguide 420, and the light-emitting optical waveguide 410 and the light-receiving optical waveguide 420. It does not affect the optical waveguide 420 for light reception.

As shown in FIGS. 16 and 17, when the screw 605 is inserted into the first to fourth insertion holes 402 to 405 and screwed into the mounting member 600, the peripheral edges of the first to fourth insertion holes 402 to 405 are opened. It can be fixed by being sandwiched between the head of the screw 605 and the mounting member 600. The number of insertion holes and the number of screws 605 are not limited to four, and may be one, for example. The peripheral edges of the first to fourth insertion holes 402 to 405 serve as fixed portions to be fixed to the mounting member 600. A washer (not shown) may be interposed between the head of the screw 605 and the peripheral edge of the first to fourth insertion holes 402 to 405.

As shown in FIG. 18, the covering member 450 may be provided at a portion fixed to the mounting member 600. In this case, the screw 605 may be arranged so as to penetrate the covering member 450 and screwed into the mounting member 600. As a result, the covering member 450 can be sandwiched and fixed between the head of the screw 605 and the mounting member 600.

As shown in FIG. 19, when the covering member 450 is provided at a portion fixed to the mounting member 600, the light emitting optical wave guide 410 and the light receiving optical waveguide 420 and / or the covering member 450 are provided on both sides of the covering member 450 in the width direction. The mounting area 602 may be provided, and the holes provided in the mounting area 602 may be fixed with screws 605, respectively. In this case, both sides of the covering member 450 in the width direction can be sandwiched and fixed between the head of the screw 605 and the mounting member 600.

As shown in FIG. 20, when the covering member 450 is provided at a portion to be fixed to the mounting member 600, the light emitting optical wave guide 410, the light receiving optical waveguide 420, and / or the covering member 450 are provided on the tip side of the covering member 450. The expanded mounting area 602 may be provided, and the holes provided in the mounting area 602 may be fixed with screws 605. In this case, the tip end side of the covering member 450 can be sandwiched and fixed between the head of the screw 605 and the mounting member 600.

As shown in FIG. 21, when the covering member 450 is provided at a portion fixed to the mounting member 600, it is cast on the tip side of the covering member 450 and the portion between the light emitting optical wave guide 410 and the light receiving optical wave guide 420. An optical waveguide 410 for light, an optical waveguide 420 for light reception, and / or a mounting area 602 in which the covering member 450 is expanded may be provided, and a hole provided in the mounting area 602 may be fixed. The tip side of the covering member 450 can be fixed by being sandwiched between the head of the screw 605 and the mounting member 600, and the portion of the covering member 450 between the light projecting optical waveguide 410 and the light receiving optical waveguide 420 is a screw. It can be fixed by penetrating 605 and screwing it into the mounting member 600.

As shown in FIG. 22, the photodetector unit 400 can also be fixed using screws 606 and washers 607. FIG. 22 is a vertical cross section orthogonal to the longitudinal direction of the photodetector unit 400, and shows a portion where the fourth insertion hole 405 is formed. The washer 607 is arranged below the photodetection unit 400. The washer 607 is formed with an annular portion 607a to be inserted into the fourth insertion hole 405. The screw 606 is inserted into the annular portion 607a of the washer 607 and screwed into the mounting member 600. At this time, since the head of the screw 606 can be received by the upper end of the annular portion 607a of the washer 607, it becomes difficult for a strong force to act in the vertical direction on the light detection unit 400, and the light projecting optical waveguide 410, Damage to the light receiving optical waveguide 420 and the light extraction member 430 can be suppressed. The fixing site is not limited to the fourth insertion hole 405, but may be any of the first to third insertion holes 402 to 404, and the same fixing site may be applied to any plurality of the through holes 402 to 405. The method can also be adopted.

The fixing method described above is an example, and various methods can be adopted as long as the light detection unit 400 is fixed to the mounting member 600. For example, a fixing method using a binding band, a wire, or the like can also be adopted. Further, the photodetector unit 400 can be fixed to the mounting member 600 by combining any two or more fixing methods among the above-described plurality of fixing methods.

Further, the connector portion 500 may be omitted, and the base end portions of the optical waveguide 410 for light projection and the optical waveguide 420 for light reception may be fixed to the optical sensor 1 so that they cannot be removed.

(Connection structure of optical waveguide)
FIG. 23A is a vertical cross-sectional view of the connecting portion of the two light projecting optical waveguides 410A and 410B, and as shown in this figure, the two light projecting optical waveguides 410A and 410B can be connected and used. .. The end face of the light projecting optical wave guide 410A and the end face of the light projecting optical wave guide 410B may be directly abutted and connected, or the end surface of the light projecting optical wave guide 410A and the end face of the light projecting optical wave guide 410B may be connected. A transparent elastic material 460 or a transparent adhesive may be interposed so that no air layer remains between them.

It is also possible to provide a continuous reinforcing member 461 from the optical waveguide 410A for light projection to the optical waveguide 410B for light projection. The reinforcing material 461 is a tape-shaped member to be attached to the lower surface of the light projecting optical wave guide 410A and the lower surface of the light projecting optical wave guide 410B, and has flexibility. The reinforcing material 461 preferably has a property of not expanding and contracting in the longitudinal direction of the light projecting optical wave guide 410A, whereby, for example, when two light projecting optical wave guides 410A and 410B are pulled in a direction away from each other. It is possible to prevent a gap from being formed between the optical waveguides 410A and 410B for light projection, and it is possible to suppress a decrease in efficiency. The reinforcing material 461 may be provided on the upper surfaces of the light-flooding optical waveguide 410A and the light-flooding optical waveguide 410B.

FIG. 23B is a plan view of the connecting portion of the two light projecting optical waveguides 410A and 410B, and as shown in this figure, the two light projecting optical waveguides 410A and 410B can be connected and used. As shown in the connecting portion located at the center in the left-right direction in FIG. 23B, the clad 412 does not have to extend to the vicinity of the interface. By abutting the cores 411 against each other, a light bond sufficient for light to propagate can be obtained. The cores 411 may be butted against each other.

(Example of forming an optical waveguide)
FIG. 24 shows a configuration example in which the optical waveguide 410 for light projection and the optical waveguide 420 for light reception are formed on a single optical waveguide forming member 470 to realize limited reflection. An optical waveguide 410 for light projection and an optical waveguide 420 for light reception are provided on both sides of the optical waveguide forming member 470 in the width direction, respectively. Although not shown in this figure, the light-flooding optical waveguide 410 and the light-receiving optical waveguide 420 are composed of a core and a clad as shown in FIG. 8A and the like.

The tip side of the optical waveguide 410 for light projection is bent in the direction approaching the optical waveguide 420 for light reception on the tip side of the optical waveguide forming member 470. The optical waveguide forming member 470 is formed with a light emitting mirror surface 432 corresponding to the tip end portion of the optical waveguide 410 for light projection. As a result, the tip of the optical waveguide 410 for light projection becomes a light projecting end, and light is projected onto the detection region R via the light emitting mirror surface 432.

Further, the tip side of the light receiving optical waveguide 420 is bent in the direction approaching the light projection optical waveguide 410 on the tip side of the optical waveguide forming member 470. The optical waveguide forming member 470 is formed with a light incident mirror surface 433 corresponding to the tip of the light receiving optical waveguide 420. As a result, the tip of the optical waveguide 420 for light reception becomes a light receiving end, and light is received from the detection region R via the light incident mirror surface 433. In this example, the light emitting mirror surface 432 and the light incident mirror surface 433 are attached to the optical waveguide forming member 470 provided with the light emitting optical waveguide 410 and the light receiving optical waveguide 420 without providing a separate light extraction member 430. Since it can be provided, the relative positional deviation between the members does not occur, and a decrease in detection accuracy can be suppressed. It can also be said that the light extraction member is integrated into the light-flooding optical waveguide 410 and the light-receiving optical waveguide 420.

FIG. 25 shows a configuration example in which a reflector 471 made of a separate member is provided at the tip of the optical waveguide 410 for light projection and the optical waveguide 420 for light reception to realize limited reflection. The reflector 471 is made of a resin material having a high light reflectance such as white, so that the tip of the optical waveguide 410 for light projection and the tip of the optical waveguide 420 for light reception are inserted and held. It has become. The tip of the light projecting optical wave guide 410 is cut in a direction inclined with respect to the longitudinal direction of the light projecting optical wave guide 410, and is abutted against the first inner surface 471a of the reflector 471. The light that has traveled through the optical waveguide 410 for light projection is reflected by the first inner surface 471a of the reflector 471, and its traveling direction is changed toward the optical waveguide 420 for light reception. The reflector 471 is provided with a light emitting mirror surface 432, and when the light traveling through the light projecting optical waveguide 410 is reflected by the first inner surface 471a of the reflector 471, it reaches the light emitting mirror surface 432 and emits the light. The mirror surface 432 advances to the detection region R.

Further, the tip of the light receiving optical waveguide 420 is also cut in a direction inclined with respect to the longitudinal direction of the light receiving optical waveguide 420, and is abutted against the second inner surface 471b of the reflector 471. The reflector 471 is provided with a light incident mirror surface 433 so as to be adjacent to the light emitting mirror surface 432. The light from the detection region R enters the second inner surface 471b of the reflector 471 via the light incident mirror surface 433, is reflected by the second inner surface 471b, and is incident on the light receiving optical waveguide 420. In this example, since the tip portions of the light-flooding optical waveguide 410 and the light-receiving optical waveguide 420 can be held by the reflector 471, relative misalignment between the members can be suppressed.

FIG. 26 is a plan view of the photodetection unit 400 showing an example of an optical waveguide pattern in consideration of reducing light loss. The vicinity of the tip side of the optical waveguide 410 for light projection extends so as to be curved while maintaining a large curvature, and the vicinity of the tip side of the optical waveguide 420 for light reception is also curved so as to maintain a large curvature. It is extending. By increasing the curvatures of the optical waveguide 410 for light projection and the optical waveguide 420 for light reception, the width of the photodetector unit 400 becomes wider, but due to the layout of the photodetector unit 400, the width of the photodetector unit 400 becomes wider. If it is acceptable, the light loss can be reduced by using a pattern having a large curvature as in this example.

As shown in FIG. 27A, a light emitting mirror surface 432 can be provided at the tip of the light projecting optical waveguide 410. Similarly, a light incident mirror surface 433 can be provided at the tip of the light receiving optical waveguide 420 (see FIG. 26).

As shown in FIG. 27B, by setting the direction of the tip surface 410a of the light projection optical waveguide 410 by the direction setting member 472, the light emission direction can be set to a direction in which limited reflection is possible. Similarly, the incident side of light can be set by a direction setting member (not shown).

FIG. 28 is a plan view of the photodetector unit 400 showing an example of an optical waveguide pattern in which the outer size is prioritized. The vicinity of the tip side of the light-emitting optical waveguide 410 extends in a direction away from the light-receiving optical waveguide 420, and the vicinity of the tip end side of the light-receiving optical waveguide 420 extends in a direction away from the light-receiving optical waveguide 410. Compared with the example shown in FIG. 26, the distance between the vicinity of the tip end side of the light emitting optical wave guide 410 and the vicinity of the tip end side of the light receiving optical wave guide 420 is set shorter. As a result, the width of the photodetector unit 400 can be narrowed, so that it is possible to cope with the case where the width of the installation location is narrow. A light emitting mirror surface 432 can be provided at the tip of the light emitting optical waveguide 410, and a light incident mirror surface 433 can be provided at the tip of the light receiving optical waveguide 420. The configurations shown in FIGS. 27A and 27B can also be applied to the example shown in FIG. 28.

FIG. 29 shows an example in which a plurality of optical fibers are arranged in a horizontal direction, respectively, in an optical waveguide 410 for light projection and an optical waveguide 420 for light reception. That is, the optical waveguide 410 for light projection is composed of a bundled optical fiber 413 in which a plurality of optical fiber wires are bundled, and the optical waveguide 410 for light projection is formed by arranging the optical fiber wires of the bundled optical fiber 413 in the horizontal direction. is made of. The light-receiving optical waveguide 420 is also composed of the bundled optical fiber 423, and the light-receiving optical waveguide 420 is formed by arranging the optical fiber lines of the bundled optical fiber 423 in the horizontal direction. The optical fiber wire of the light projecting optical waveguide 410 and the optical fiber wire of the light receiving optical waveguide 420 are covered by the upper covering member 440 and the lower covering member 450. Although not shown, the horizontal end of FIG. 29 of the upper covering member 440 and the lower covering member 450 sandwiching the light-flooding optical waveguide 410 and the light-receiving optical waveguide 420 above and below is the covering member 440. And the lower covering member 450 can be attached and fixed.

FIG. 30 shows an example of limited reflection that emits light from the tip of an optical waveguide. In this example, the core 411 of the light-emitting optical waveguide 410 reaches the tip of the light-emitting optical waveguide 410, and the core 421 of the light-receiving optical waveguide 420 reaches the tip of the light-receiving optical waveguide 420. Has reached. Therefore, light can be emitted from the tip of the light projecting optical wave guide 410 in the longitudinal direction of the light projecting optical wave guide 410 to irradiate the work WK. The light from the detection region R can be incident on the tip of the light receiving optical waveguide 420.

In the example shown in FIG. 5, light is emitted from the main surface of the light projecting optical waveguide 410 to the detection region, and the light reflected by the work WK is received by the main surface of the light receiving optical waveguide 420. However, in the example shown in FIG. 30, the end surface (side surface) on the distal end side of the optical waveguide 410 for light emission is the light emitting surface, and the end surface (side surface) on the distal end side of the optical waveguide 420 for light reception is the light receiving surface. In this way, it is possible to use a surface other than the main surface of the light-flooding optical waveguide 410 and the light-receiving optical waveguide 420 as the light-emitting surface.

Further, as shown in FIGS. 24, 26, 28, and 30, the core pattern can be freely drawn in the plane other than the linear pattern in the optical waveguides 410 and 420, and the optical path in the optical waveguides 410 and 420 can be freely drawn. High degree of design freedom.

FIG. 31 shows another example of limited reflection that emits light from the tip of an optical waveguide. In this example, the light that has traveled through the core 411 of the light projecting optical wave guide 410 may be emitted from the tip of the light projecting optical wave guide 410 in the longitudinal direction of the light projecting optical wave guide 410 to irradiate the work WK. can. The light from the detection region R can be incident from the tip of the light receiving optical waveguide 420. The example shown in FIG. 31 is the same optical path as in FIG. 30, but instead of the pattern in the optical waveguide, by cutting the side surface of the optical waveguide diagonally, the difference in refractive index between the optical waveguide and the outside is used. It is also possible to change the optical path.

As shown in FIG. 32, light can be emitted and incident from the side surface of the optical waveguide. In this example, the light that has traveled through the core 411 of the light projecting optical wave guide 410 can irradiate the work WK from the side surface of the light projecting optical wave guide 410. Similarly, the light from the detection region R can be incident on the light receiving optical waveguide 420 from the side surface. This can be achieved by the formation pattern of the cores 411 and 412.

FIG. 33 shows another example of limited reflection that emits light from the side surface of an optical waveguide. By providing the light emitting mirror surface 432 at the tip of the light projecting optical wave guide 410, the work WK can be irradiated with light from the side surface of the light projecting optical wave guide 410. By providing the light incident mirror surface 433 at the tip of the light receiving optical waveguide 420, the light from the detection region R can be incident on the light receiving optical waveguide 420 from the side surface. In this example, the formation pattern of the cores 411 and 412 may remain linear.

FIG. 34 shows an example in which the photodetector unit 400 is used as a multi-point reflection type photodetector unit. The photodetector unit 400 is formed with a core 411 (421) capable of projecting light in multiple directions and receiving light from multiple directions. As a result, light is emitted from the tip of the photodetection unit 400 in multiple directions, and light from multiple directions can be received by the tip of the photodetection unit 400, so that, for example, the surface of the work WK has irregularities. Even if it exists, its influence can be reduced and the detection accuracy can be improved.

As shown in FIG. 35, the tip of the light-flooding optical waveguide 410 and the tip of the light-receiving optical waveguide 420 of the photodetection unit 400 may be bent. As a result, the light of the light projection optical waveguide 410 can be irradiated in the bent direction, and the light from the detection region R can be received from the direction in which the light receiving optical waveguide 420 is bent. Further, the tip of the optical waveguide 410 for light projection and the tip of the optical waveguide 420 for light reception can be bent according to the core pattern in a plane without being bent.

FIG. 36A shows an example in which the optical waveguide and the mirror member are combined. The light projection mirror member 480 is arranged so as to face the tip end portion of the light projection optical waveguide 410. A light emitting mirror surface 480a is formed on the light emitting mirror member 480, and light can be emitted above the light emitting optical waveguide 410 by the light emitting mirror surface 480a. Further, the light receiving mirror member 481 is arranged so as to face the tip end portion of the light receiving optical waveguide 420. A light incident mirror surface 481a is formed on the light receiving mirror member 481, and light can be incident from above the light receiving optical waveguide 420 by the light incident mirror surface 481a.

FIG. 36B shows another example of combining the optical waveguide and the mirror member. The tip of the light projecting optical wave guide 410 and the light projecting mirror member 480 are arranged so as to abutt against each other, and even with this configuration, light is emitted above the light projecting optical wave guide 410 by the light emitting mirror surface 480a. Can be done. Further, the tip of the light-receiving optical waveguide 420 and the light-receiving mirror member 481 are abutted and arranged, and light can be incident from above the light-receiving optical waveguide 420 also with this configuration.

FIG. 37 shows an example of irradiating the regression reflector 485 with the light emitted from the light projection optical waveguide 410. In this example, the light reflected from the regression reflector 485 can be received at the tip of the light receiving optical waveguide 420. If a work WK exists between the retroreflector 485 and the light projecting optical waveguide 410 and the light receiving optical waveguide 420, the work WK blocks the light, so that the light receiving optical waveguide 420 receives the light. You will not be able to. This example can be applied to a detection method utilizing this.

(Transmissive light detection unit)
In the above example, the case where the present invention is applied to the detection method by limited reflection has been mainly described, but the present invention can also be used as a transmission type photodetection unit 400.

FIG. 38A shows an example of the transmission type photodetection unit 400 in the case where the light emitting optical waveguide 410 and the light receiving optical waveguide 420 extend in the same direction. The light emitting mirror surface 432 provided at the tip of the light projecting optical wave guide 410 changes the direction of the light traveling through the light projecting optical wave guide 410 toward the light receiving optical wave guide 420. The light emitted from the light-emitting optical wave-guide 410 is received by the light-receiving optical wave-guide 420, is directed by the light incident mirror surface 433, and travels through the light-receiving optical wave-guide 420.

FIG. 38B shows an example of the transmission type photodetection unit 400 when the light-emitting optical wave guide 410 and the light-receiving optical wave guide 420 extend in opposite directions. As in this example, the reflection angle of the light advancing through the light projecting optical wave guide 410 can be set by the light emitting mirror surface 432, whereby the light projecting optical wave guide 410 and the light receiving optical wave guide 420 are reversed. The work WK can be detected even if it is arranged so as to extend in the direction.

FIG. 39 shows an example in which the tip of the optical waveguide 410 for light projection and the tip of the optical waveguide 420 for light reception face each other. As in this example, the tip of the light-flooding optical waveguide 410 and the tip of the light-receiving optical waveguide 420 are arranged at predetermined intervals, and the light emitted from the tip of the light-flooding optical waveguide 410 is emitted. Light can be received at the tip of the light receiving optical waveguide 420. In this case, the work WK between the tip of the light-flooding optical waveguide 410 and the tip of the light-receiving optical waveguide 420 can be detected.

FIG. 40 shows an example in which the work WK is detected in the light detection unit 400. The light detection unit 400 is provided with a work WK insertion portion 459 formed of recesses and holes. The light that has traveled through the light-flooding optical waveguide 410 is projected into the insertion portion 459 and can be received at the tip of the light-receiving optical waveguide 420. When the work WK is inserted into the insertion portion 459, the light projected from the optical waveguide 410 for light projection is blocked.

FIG. 41 shows an example of a transmissive photodetector unit 400 in which a large number of optical paths are formed. Light is projected from the tip of the optical waveguide 410 for light projection so as to form a large number of optical paths. Corresponding to this, the tip of the light receiving optical waveguide 420 can receive light from a large number of optical paths. In this example, the detection range can be widened.

(Connector part 500)
The form shown in FIG. 4 is a form having a connector portion 500, and shows a state before the connector portion 500 is connected to the light emitting optical wave guide 410 and the light receiving optical wave guide 420. The connector portion 500 is a member that connects the base end portion of the light projecting optical wave guide 410 and the base end portion of the light receiving optical wave guide 420. The connector portion 500 directly or indirectly connects the base end portion of the light emitting optical waveguide 410 and the base end portion of the light receiving optical waveguide 420 to the light emitting hole 376 and the light receiving hole 378 of the optical sensor 1, respectively. It is a member that is optically connected and is detachably attached to a light emitting hole 376 and a light receiving hole 378. The material constituting the connector portion 500 can be, for example, a resin material, and the color of the resin material is preferably a color that does not transmit light or a color that hardly transmits light.

The connector portion 500 according to the first example of the present embodiment shown in FIGS. 42 to 46 has a main body portion 501, a light emitting side convex portion 502 and a light receiving side convex portion 503 protruding from the main body portion 501. The connector portion 500 can integrate the light projecting optical waveguide 410 and the light receiving optical waveguide 420. The light-emitting side convex portion 502 and the light-receiving side convex portion 503 are portions that are inserted into the light-emitting hole 376 and the light-receiving hole 378 (shown in FIG. 3) of the optical sensor 1, respectively. Therefore, the distance between the light emitting side convex portion 502 and the light receiving side convex portion 503 is substantially the same as the distance between the light emitting hole 376 and the light receiving hole 378 of the optical sensor 1.

The cross section of the light projecting side convex portion 502 is a substantially circular shape surrounding the periphery of the light projecting optical waveguide 410, and substantially coincides with the cross section of the light projecting hole 376 of the optical sensor 1. The outer diameter of the projection side convex portion 502 is set to be larger than the thickness dimension of the light projection optical waveguide 410. Further, the outer diameter of the light projecting side convex portion 502 can be set to be slightly smaller than the light projecting hole 376 of the optical sensor 1, but the state in which the light projecting side convex portion 502 is inserted into the light projecting hole 376. The gap formed between the two is very small. As a result, the projection side convex portion 502 is positioned in the radial direction. Further, the length of the light projecting side convex portion 502 corresponds to the depth of the light projecting hole 376, and the light projecting side convex portion 502 with the light projecting side convex portion 502 inserted into the light projecting hole 376. The tip surface of the reflector is in contact with or close to the end surface of the reflector 380 shown in FIG. The insertion depth of the projecting side convex portion 502 can be defined by bringing the tip surface of the projecting side convex portion 502 into contact with the end surface of the reflector 380. The insertion depth of the projection side convex portion 502 can also be specified by pressing the main body portion 501 against a part of the optical sensor 1.

The light receiving side convex portion 503 is also configured in the same manner as the light emitting side convex portion 502, and has a substantially circular shape surrounding the light receiving optical waveguide 420. Positioning is performed in the radial direction and the insertion direction in a state where the light receiving side convex portion 503 is inserted into the light receiving hole 378 of the optical sensor 1.

As shown in FIG. 44, the main body 501 is formed with a light guide insertion hole 501a into which the base end of the light guide 401 is inserted. An elastic material 504 made of rubber, an elastomer, or the like is provided between the base end portion of the light guide portion 401 and the inner surface of the light guide portion insertion hole 501a. The elastic material 504 is formed so as to cover the outer peripheral surface of the base end portion of the light guide portion 401. A plurality of engaging protrusions 504a are formed on the elastic material 504. The main body 501 is formed with an engaging hole 501b with which the engaging projection 504a of the elastic material 504 is engaged. The elastic material 504 is prevented from coming off from the main body 501 in a state where the engaging protrusion 504a of the elastic material 504 is engaged with the engaging hole 501b of the main body 501. The elastic material 504 may be omitted.

The light emitting optical waveguide 410 of the light guide unit 401 passes through the inside of the light emitting side convex portion 502. As in the first example shown in FIG. 47, the tip end portion of the light projecting optical waveguide 410 reaches the tip surface of the light projecting side convex portion 502 and is exposed to the tip surface. The tip of the light projecting optical wave guide 410 and the tip surface of the light projecting side convex portion 502 may be flush with each other, or the tip of the light projecting optical wave guide 410 may be the tip surface of the light projecting side convex portion 502. You may be deep inside. When it is recessed, it is possible to prevent damage to the tip of the optical waveguide 410 for light projection. When it is recessed, the distance between the tip of the light projecting optical waveguide 410 and the tip surface of the light projecting side convex portion 502 is preferably set to 0.5 mm or less. This is to suppress a decrease in the amount of light.

As shown in FIG. 48, the light projecting side convex portion 502 is formed with a concave light projecting side accommodating portion 502a for accommodating the light projecting optical waveguide 410. The light emitting side accommodating portion 502a is opened on the outer peripheral surface of the light emitting side convex portion 502. The light emitting side accommodating portion 502a is provided with a holding member 505 for holding the light emitting optical waveguide 410 by holding it down. The pressing member 505 engages with the inner surface of the light emitting side accommodating portion 502a and is held at a predetermined position, whereby the relative position of the light emitting optical waveguide 410 with respect to the light emitting side convex portion 502 is determined. Therefore, the light projecting side convex portion 502 is inserted into the light projecting hole 376 of the optical sensor 1 and is located at the center position of the light emitting surface of the light emitting element 104 shown in FIG. Position the tip of the. The pressing member 505 may be omitted, and the optical waveguide 410 for light projection may be adhered to the inner surface of the light emitting side accommodating portion 502a.

Further, the light receiving side convex portion 503 is formed with a concave light emitting side accommodating portion 503a for accommodating the light receiving optical waveguide 420. The light receiving side accommodating portion 503a is open on the outer peripheral surface of the light receiving side convex portion 503. The light receiving side accommodating portion 503a is provided with a pressing member 506 for pressing and holding the light receiving optical waveguide 420. The pressing member 506 engages with the inner surface of the light receiving side accommodating portion 503a and is held at a predetermined position, whereby the relative position of the light receiving optical waveguide 420 with respect to the light receiving side convex portion 503 is determined. Therefore, in a state where the light receiving side convex portion 503 is inserted into the light receiving hole 378 of the optical sensor 1, the tip end portion of the light receiving optical waveguide 420 is placed at the center position of the light receiving surface of the light receiving element 204 shown in FIG. Position.

FIG. 49 shows the connector portion 500 according to the second example of the present embodiment. The main body 510 of the connector portion 500 of the second example is composed of an upper member 511 and a lower member 512. The upper member 511 and the lower member 512 may be integrated with a screw or the like, or may be integrated with an adhesive or the like.

The lower member 512 has a first groove portion 512a that holds the light projecting optical waveguide 410 protected by the protective elastic material 513, and a second groove portion 512a that holds the light receiving optical waveguide 420 protected by the protective elastic material 514. A groove portion 512b is formed. The upper member 511 is formed with a first fitting portion 511a to be fitted into the first groove portion 512a and a second fitting portion 511b to be fitted into the second groove portion 512b. By fitting the first fitting portion 511a into the first groove portion 512a, the optical waveguide 410 for light projection can be sandwiched and held between the tip surface of the first fitting portion 511a and the bottom surface of the first groove portion 512a. By fitting the second fitting portion 511b into the second groove portion 512b, the light receiving optical waveguide 420 can be sandwiched and held between the tip surface of the second fitting portion 511b and the bottom surface of the second groove portion 512b.

Further, the upper member 511 is formed with a third fitting portion 511c to be fitted into the light emitting side accommodating portion 502a and a fourth fitting portion 511d to be fitted into the light emitting side accommodating portion 503a. The third fitting portion 511c and the fourth fitting portion 511d are alternative portions to the pressing members 505 and 506 of the first example, and the third fitting portion 511c and the fourth fitting portion 511d provide the optical waveguide 410 for light projection and the optical waveguide 410 and the fourth fitting portion 511d. The light receiving optical waveguide 420 can be held down.

FIG. 50 shows the connector portion 500 according to the third example of the present embodiment. In the connector portion 500 of the third example, the main body portion 520, the light emitting side convex portion 522, and the light receiving side convex portion 523 are composed of separate members. The light emitting side convex portion 522 and the light receiving side convex portion 523 are each composed of rod-shaped members. The projection side convex portion 522 is composed of a base member 522a having a partially cutout shape and a fitting member 522b that fits into the cutout portion. By arranging the light projecting optical wave guide 410 in the notched portion of the base member 522a, the light projecting optical wave guide 410 can be positioned with respect to the base member 522a. By fitting the fitting member 522b to the notched portion of the base member 522a in the state where the light projecting optical wave guide 410 is positioned, the light projecting optical wave guide 410 can be held so as not to move. It has become. The light receiving side convex portion 523 is also configured in the same manner, and has a base member 523a and a fitting member 523b.

As shown in FIG. 51, the main body portion 520 is held in a state where the light emitting side convex portion 522 is inserted and the light emitting side holding hole 520a and the light receiving side convex portion 523 are inserted. A light receiving side holding hole 520b is formed. The light projecting side convex portion 522 can be rotated around the center line of the light projecting side convex portion 522 with the light emitting side convex portion 522 inserted into the light emitting side holding hole 520a. Further, the light receiving side convex portion 523 can be rotated in the same manner. The main body 520 can be made of rubber or the like. The main body 520 may be omitted.

As shown in FIG. 52, the optical sensor 1 may be provided with the pre-installation adapter 540 in advance. In this example, the photodetector unit 400 can be connected to the optical sensor 1 via the pre-installed adapter 540.

As shown in FIG. 53, the shape of the light emitting hole 376 and the light receiving hole 378 insertion port 376a and 378a of the optical sensor 1 may be a slit shape. Since the slit-shaped insertion ports 376a and 378a substantially match the cross-sectional shapes of the light-flooding optical waveguide 410 and the light-receiving optical waveguide 420, the light-flooding optical waveguide 410 and the light-receiving light are received without providing the connector portion 500. The base end portion of the optical waveguide 420 can be directly connected to the light emitting hole 376 and the light receiving hole 378.

FIG. 54 shows the light emitting side connector portion 550 and the light receiving side connector portion 551 according to the fourth example of the embodiment. The light-emitting side connector portion 550 is formed in a columnar shape that can be positioned by being inserted into the light-emitting hole 376 of the optical sensor 1. The light projecting side connector portion 550 is formed with a slit-shaped hole portion 550a into which the light projecting optical waveguide 410 is inserted. The light-receiving side connector portion 551 is also configured in the same manner, and is formed in a columnar shape that can be positioned by being inserted into the light-receiving hole 378 of the optical sensor 1, and has a slit-shaped hole portion 551a.

The light emitting side connector part 550 and the light receiving side connector part 551 are inserted all the way into the light emitting hole 376 and the light receiving hole 378 of the optical sensor 1, and the light emitting optical waveguide 410 and the light receiving hole are inserted into the holes 550a and 551a. By inserting the optical waveguide 420 all the way, it can be connected to the optical sensor 1.

(Structure of relay part)
As in the structure of the first example of the relay portion shown in FIGS. 55A, 55B, 55C, 56A and 56B, the optical waveguide 410 for light projection, the optical waveguide 420 for light reception, and the bundled optical fiber are connected to the relay connector portion. It can be connected by 580. The relay connector portion 580 is connected to the base end portion of the optical waveguide 410 for light projection, and is optical-coupled to the light projection hole 376 of the optical sensor 1 so as to be optically coupled to the light projection side optical fiber 560 and the optical wave guide for light reception. It is a member that integrally bundles the light receiving side optical fiber 561 that is connected to the base end portion of 420 and is optically coupled to the light receiving hole 378 of the optical sensor 1 so as to be insertable and removable. The light emitting side optical fiber 560 and the light receiving side optical fiber 561 are made of a bundled optical fiber in which a plurality of optical fiber wires are bundled.

The relay connector unit 580 can be used when extending the photodetection unit 400. The relay connector portion 580 includes a connector case 581 made of a resin material or the like that does not transmit light or hardly transmits light. The light emitting side optical fiber 560 and the light receiving side optical fiber 561 are held by the fiber adapters 560b and 561b in a state where the optical fiber lines 560a and 561a are arranged in the horizontal direction (the width direction of the optical waveguides 410 and 420), respectively. .. The fiber adapters 560b and 561b are fixed in a state of being housed in the connector case 581. In the connector case 581, the light emitting side and the light receiving side are optically isolated.

A light-emitting side adapter 490 and a light-receiving side adapter 491 are attached to the base ends of the light-emitting optical waveguide 410 and the light-receiving optical waveguide 420, respectively. The floodlight side adapter 490 and the light receiving side adapter 491 are fixed in a state of being housed in the connector case 581.

The arrangement direction of the optical fiber lines 560a constituting the light projecting side optical fiber 560 coincides with the width direction of the light projecting optical wave guide 410, and the optical fiber line 560a has the width of the light projecting optical wave guide 410. It is arranged from the part corresponding to one end in the direction to the part corresponding to the other end. Similarly, on the light receiving side, the arrangement direction of the optical fiber wires 561a and the width direction of the light receiving optical waveguide 420 coincide with each other, and the optical fiber wire 561a starts from a portion corresponding to one end in the width direction of the light receiving optical waveguide 420. It is arranged up to the part corresponding to the other end.

A projecting-side rod lens 582 long in the width direction of the projecting optical waveguide 410 is provided between the tip of the projecting-side optical fiber 560 and the base end of the projecting optical waveguide 410. Further, a light receiving side rod lens 583 that is long in the width direction of the light receiving optical waveguide 420 is provided between the tip end portion of the light receiving side optical fiber 561 and the base end portion of the light receiving optical waveguide 420. A transparent elastic material or adhesive may be provided instead of the light emitting side rod lens 582 and the light receiving side rod lens 583. Further, the light emitting side rod lens 582 and the light receiving side rod lens 583 may be omitted, and the tip end portion of the light emitting side optical fiber 560 and the base end portion of the light emitting optical waveguide 410 may be abutted against each other. The tip end of the optical fiber 561 and the base end of the light receiving optical waveguide 420 may be abutted against each other. It should be noted that one core may be used without using a plurality of optical fiber wires.

Then, instead of combining the light-flooding optical waveguide 410 and the light-receiving optical waveguide 420 into one case 581, the light-flooding optical waveguide 410 and the light-receiving optical waveguide 420 may be divided.

Further, the light leaked due to the coupling between the tip of the light projecting optical fiber 560 and the base end of the light emitting optical waveguide 410 is used as an operation indicator, the tip of the light receiving side optical fiber 561 and the light receiving optical waveguide 420. The light leaked due to the coupling of the base end portion can also be used as an output indicator lamp 585 (shown in FIG. 55A).

Although the indicator lamp 585 is provided on the light receiving side in FIG. 55A, it may be provided on the light emitting side. Further, the light source of the indicator lamp may be the LED 212 shown in FIG. 3, or the light emitted from the light emitting element 104 used for detection or the light reflected by the work WK. Further, it may be realized by partially cutting the surface of the indicator lamp or the optical waveguide, but the leaked light generated at the coupling end face of the optical waveguide 410 or 420 and the optical fiber 560 or 561 can be successfully detected by the indicator lamp. By doing so, the loss of the detected light can be reduced.

As shown in FIGS. 55A and 55B, the relay connector 580 may also be provided with a through hole 588. Of the through holes 588 of the relay connector 580, the through hole on the tip end side communicates with the through hole provided between the optical waveguides or in the optical light guide path.

Further, a reinforcing plate 461 is provided at the tips of the optical waveguides 410 and 420. The reinforcing plate 461 is preferably made of metal or resin, and is thin and has high strength. Further, by attaching the reinforcing plate 461 on the lower covering member 450 with an adhesive or double-sided tape, bending or deformation of the tip detection portion can be suppressed.

The reinforcing plate 461 may be provided only on the back surface of the optical waveguides 410 and 420, only on the front surface, or on both sides. In FIG. 56, the reinforcing plate 461 is provided only on the back surfaces of the optical waveguides 410 and 420. Further, the surface on which the reinforcing plate 461 is provided is not limited to the main surfaces of the optical waveguides 410 and 420, and the end faces of the three sides of the detection unit can be surrounded by the reinforcing plate 461. Further, the reinforcing plate 461 is wider than the optical waveguide 410, 420 or the sheet-shaped covering member.

The reinforcing plate 461 may also be provided with holes that communicate with the third through holes 404 and the fourth through holes 405 of the optical waveguides 410 and 420. This hole can be used as a fixing hole for screwing.

The fixing method of the reinforcing plate 461 is not limited to screwing, and the reinforcing plate 461 can also be fixed on the fixing surface by a method such as adhesion, double-sided tape, or sandwiching.

Although not shown, characters can be written on the front and back surfaces of the tapes of the relay connector case 581 or the optical waveguides 410 and 420 for display discrimination by sticker, silk printing, engraving, or the like.

Although the outline of the relay connector portion 581 has been described with reference to FIGS. 55A to 55C, when the optical waveguides 410 and 420 and the optical fibers 560 and 561 are optically coupled to each other at the relay connector portion 581 with reference to FIG. 56B. I will briefly explain how to assemble. By adopting the configuration as shown in FIG. 56B, the tip end portion of the light receiving side optical fiber 561 and the base end portion of the light receiving optical waveguide 420 can be efficiently abutted.
(Explanation of the configuration of the relay connector portion of FIG. 56B)
1. 1. The tip coatings of the optical fibers 560 and 561 (bundle fibers) are stripped, and the bundle fibers are lined up on the fiber adapters 560b and 561b.
2. The optical waveguides 410 and 420 are taped together to determine the pitch interval in the width direction, and the coupling portion with the optical fibers 560 and 561 is slightly projected.
3. 3. The fiber adapters 560b and 561b are fitted into the connector case 581, and the width direction is positioned by the positioning boss (on the ellipse).
4. The optical waveguides 410 and 420 are fitted into the connector case 581, and the width direction is positioned by the positioning boss (on the ellipse).
5. The fiber adapters 560b, 561b and the optical waveguide 410, 420 fitted in the connector case 581 are moved in the longitudinal direction, and the fiber adapters 560b, 561b and the optical waveguide 410, with the optical coupling end face abutted or a small gap left. The root of 420 is fixed with a firm adhesive, and the optical coupling portion is fixed by filling the bonding gap with a transparent elastic material or adhesive.
6. Finally, the lid of the connector case 581 is closed. At this time, the lid should not be opened by adhesive, double-sided tape, or welding.

As in the structure of the second example of the relay portion shown in FIGS. 57 and 58, the relay connector portion 590 may be composed of three parts. The relay connector portion 590 includes a first holding member 591 that holds the light emitting side optical fiber 560 and the light receiving side optical fiber 561, and a second holding member 592 that holds the light emitting optical waveguide 410 and the light receiving optical waveguide 420. It includes an intermediate member 593 arranged between the first holding member 591 and the second holding member 592.

As shown in FIG. 58, the first holding member 591 is formed with holding holes 591a and 591b in which the tip portions of the light emitting side optical fiber 560 and the light receiving side optical fiber 561 are held in a state of being inserted. The second holding member 592 is formed with holding holes 592a and 592b in which the base ends of the light-flooding optical waveguide 410 and the light-receiving optical waveguide 420 are inserted.

The first holding member 591, the intermediate member 593, and the second holding member 592 are integrated by a screw 594. That is, the screw 594 penetrates the first holding member 591 and the intermediate member 593 from the first holding member 591 side, and then is screwed into the second holding member 592. The position of the screw 594 is not limited to the position shown in FIG. 58. For example, as in the third example of the relay portion shown in FIG. 59, if the distance between the light emitting side optical fiber 560 and the light receiving side optical fiber 561 is wide. A screw 594 can be provided between the light emitting side optical fiber 560 and the light receiving side optical fiber 561.

Further, the optical fibers 560 and 561 extending from the relay connector 580 may be used as free-cut optical fibers. For a free-cut optical fiber, the length of the optical fiber can be adjusted by using a free-cut jig.

Further, in the first to third examples of the relay portion, when a small-diameter optical fiber is used as the optical fibers 560 and 561 extending from the relay connector portion 580 to the optical sensor 1 side, the optical fiber and optics are used. An adapter for connecting to the type sensor 1 may be used to facilitate optical coupling.

Any fiber diameter of the optical fibers 560 and 561 can be used. Similar to the tip of the optical waveguide, it is desired that the relay connector portion 580 be made thinner in order to increase the degree of freedom in the installation space. The larger the diameter of the optical fiber, the thicker the relay connector 580. Therefore, it is better that the fiber diameter is as small as possible, but there is a degree of freedom in design that can be freely designed in consideration of the coupling efficiency with the optical waveguide.

In the present embodiment, as shown in FIGS. 6 and 8, the core 411 has been described as having one layer, but the present invention is not limited to this, and the core 411 may have two or more layers.

Further, as shown in FIG. 1, when the optical sensor 1 is installed upright so that the display unit 334 is located on the upper surface, the light emitting hole 376 and the light receiving hole 378 are provided with respect to the housing 10. They are arranged side by side in the vertical direction, and the light emitting path and the light receiving path of the optical waveguide are arranged in the horizontal direction of the sheet. Therefore, since two vertically aligned lines are arranged horizontally, a twist portion for horizontally arranging vertically aligned objects is required between the optical sensor 1 and the tip of the optical waveguide. It becomes. It is easier to twist a thin linear optical fiber than to twist a sheet-shaped optical waveguide, and it is possible to reduce disconnection, light leakage, and loss.

(Action and effect of the embodiment)
According to the present embodiment, the optical waveguides 410 and 420 form a wide sheet in the horizontal direction, and have cores 411 and 421 and clads 412 and 422 provided in layers in the vertical direction. It is possible to secure the amount of light of the optical waveguides 410 and 420 while thinning the optical waveguides 410 and 420. Since the clads 412 and 422 of the optical waveguides 410 and 420 are covered with sheet-shaped covering members 440 and 450, and the covering members 440 and 450 serve as an installation surface for the mounting target, thin optical waveguides 410 and 420 are mounted. It can be easily installed on the target.

Further, the optical waveguides 410 and 420 can be connected to the optical sensor 1 by the connector portion 500. Since the connector portion 500 is detachably attached to the optical sensor 1, it is easy to connect the photodetector unit 400 to the optical sensor 1 or replace the photodetector unit 400 as needed. Become.

Further, the photodetection unit 400 is easy to handle as a unit because the light emitting / receiving side is integrated by a covering member, a connector portion, a relay connector portion, and the like.

The above embodiments are merely exemplary in all respects and should not be construed in a limited way. Furthermore, all modifications and modifications that fall within the equivalent scope of the claims are within the scope of the present invention.

As described above, the present invention can be used, for example, when detecting the presence or absence of an article.

1 Optical sensor 104 Light emitting element 204 Light receiving element 308a Signal generation unit 376 Light projection hole (light projection connection)
378 Light receiving hole (light receiving connection)
400 Photodetection Units 402 to 405 First to Fourth Insertion Holes (Fixed Part)
410 Optical waveguide for light projection 411 Core 412 Clad 420 Optical waveguide for light reception 421 Core 422 Clad 440 Upper coating member 430 Light extraction member 432 Light emission mirror surface (light emission part)
433 Light incident mirror surface (light incident part)
450 Lower covering member 461 Reinforcing plate (reinforcing metal)
500 Connector part 502 Light emitting side convex part 503 Light receiving side convex part 560 Light receiving side optical fiber 560a Optical fiber line 561 Light receiving side optical fiber 561a Optical fiber line 582 Light emitting side rod lens 583 Light receiving side rod lens 585 Indicator light 588 Intermediate connector Through hole of the part

Claims (18)

A light emitting element that projects the detection light toward the detection area,
A light receiving element that receives the detection light from the detection region and
A light projecting connection for optical coupling to the light emitting element,
A light-receiving connection for optical coupling to the light-receiving element,
An optical detection unit connected to an optical sensor having a signal generation unit that compares a light receiving signal generated by the light receiving element with a threshold value and generates a detection signal indicating a comparison result.
It guides light between the first end and the second end to form a wide sheet in the horizontal direction, has a core and a clad surrounding the core, and the core and the clad are layered in the vertical direction. The first end is connected to a light projecting connection or a light receiving connection so as to be photocoupled to the light emitting element or the light receiving element of the optical sensor, and the second end is projected. An optical waveguide that projects light into the detection area or receives light from the detection area as the light end or light receiving end.
The first end of the optical waveguide is connected, and the first end of the optical waveguide is optically optically connected to the light projection connection or the light reception connection of the optical sensor. And a connector part that is detachably attached to the light emitting connection part or the light receiving connection part
Light detection unit with. In the photodetection unit according to claim 1,
The connector portion is a light detection unit having a convex portion inserted into the light projection connection portion or the light receiving connection portion. In the photodetection unit according to claim 2.
The first end of the optical waveguide is exposed on the tip surface of the convex portion.
The convex portion is inserted into the light projecting connection portion or the light receiving connection portion, and the first end portion is placed at the center position of the light emitting surface of the light emitting element or the light receiving surface of the light receiving element. Light detection unit for positioning. In the photodetection unit according to claim 1,
The optical waveguide is connected to the light projecting connection portion of the optical sensor, and the optical wave guide for light projecting is connected to the light projecting connection portion, and the second end portion serves as a light projecting end to project light into a detection region, and the optical wave guide of the optical sensor. The second end is connected to the light receiving connection and includes a light receiving optical waveguide that receives light from the detection region as a light receiving end.
The connector portion is connected to the first end portion of the light projecting optical waveguide, and is optically coupled to the light projecting connection portion so as to be optically coupled to the light projecting side optical fiber, and the light receiving optical wave guide. An optical detection unit that integrally bundles a light-receiving side optical fiber that is connected to one end and is photocoupled to the light-receiving connection so that it can be inserted and removed. In the photodetection unit according to claim 4,
The light emitting side optical fiber and the light receiving side optical fiber are optical detection units that are bundled optical fibers in which a plurality of optical fiber wires are bundled. In the photodetection unit according to claim 5.
On the connection side of the light projecting side optical fiber with the light projecting optical waveguide, a plurality of fiber lines constituting the light projecting side optical fiber are arranged side by side in the width direction of the light projecting optical wave guide. Light detection unit. In the photodetection unit according to claim 6.
A light detection unit provided with a rod lens, a transparent elastic material, or a transparent adhesive material long in the width direction of the light projecting optical wave guide between the light projecting side optical fiber and the light projecting optical wave guide. .. A light projecting hole that is optically coupled to the light projecting element inside the housing,
A photodetector unit that is removably connected to an optical sensor having a light receiving hole that is optically coupled to a light receiving element in the housing.
The end on the sensor side is optically coupled to the light projection hole, the detection end is arranged so as to project the detection light toward the detection region, and a sheet-like shape having a core through which the light passes and a clad surrounding the core is provided. With the first optical waveguide
The sensor-side end is optically coupled to the light-receiving hole, the detection end is arranged to receive the detection light from the detection region, and a sheet-like second optical wave having a core through which the light passes and a clad surrounding the core. Waveguide and
A connector portion that integrates the first optical waveguide and the second optical waveguide,
A projection-side convex portion provided on the connector portion, having a substantially circular cross section surrounding the sensor-side end portion of the first optical waveguide, and having a size substantially the same as that of the projection hole.
A light-receiving side convex portion provided on the connector portion, having a substantially circular cross section surrounding the sensor-side end portion of the second optical waveguide, and having a size substantially the same as that of the light-receiving hole.
Light detection unit with. In the photodetection unit according to claim 8.
A photodetection unit in which the outer diameter of the projection side convex portion is set to be larger than the thickness dimension of the first optical waveguide. In the photodetection unit according to claim 8.
The light emitting side convex portion and the light receiving side convex portion are optical detection units which are optical fibers. In the photodetection unit according to any one of claims 8 to 10.
The light emitting hole and the light receiving hole of the optical sensor are arranged side by side in the vertical direction with respect to the housing.
The light emitting path and the light receiving path of the optical waveguide are arranged in a sheet-like horizontal direction.
An optical detection unit having a twisted portion between the detection region of the optical waveguide and the connection hole. In the photodetection unit according to claim 11.
The twisted portion is an optical detection unit which is an optical fiber portion. In the photodetection unit according to any one of claims 1 to 7.
Between the first end and the second end of the optical waveguide, an indicator lamp that takes out the light passing through the core of the optical waveguide to the outside is provided on the optical waveguide on the light emitting side or the light receiving side. unit. In the photodetection unit according to any one of claims 1 to 7.
The light emitting connection portion and the light receiving connecting portion are circular holes.
The portion of the connector portion that is detachably attached to the light projection connection portion or the light receiving connection portion is a photodetection unit in which the cores of the optical waveguide are arranged in a sheet shape. In the photodetection unit according to any one of claims 1 to 14.
The connector portion is a photodetection unit that grips the optical waveguide on the light emitting side and the light receiving side. In the photodetection unit according to any one of claims 1 to 15.
An optical detection unit having a through hole for fixing in the connector portion. In the photodetection unit according to any one of claims 1 to 16.
The portion where the optical fiber and the optical waveguide are optically coupled is an optical detection unit in the connector. In the photodetection unit according to any one of claims 1 to 17.
A photodetector unit provided with holes for fixing in the optical waveguide.

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