Optical sensor

Abstract

To obtain an optical sensor that adopts an above-mentioned transmission type photointerrupter configuration, and that can achieve measures against stray light from a light emitting element to a light receiving element with a configuration at reduced cost.SOLUTION: An emission part in a first portion is more distant from a light emitting element than an incident part on which light from the light emitting element in the first portion is incident, and light from the first portion is emitted from the emission part. The width of the emission part in a direction perpendicular to both a direction perpendicular to a surface of a substrate and a direction in which light emitted from the light emitting element is directed from the first portion to a second portion, is smaller than the width of the incident part in the direction perpendicular to both directions.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to an optical sensor that detects an object by using a light-emitting element and a light-receiving element, and to a configuration thereof. [Background technology]

[0002] A conventional transmissive photointerrupter, as shown in Figure 18, has a lead type LED (light emitting element), a lead type Ptr (light receiving element), and a housing. Hereafter, the light emitting element will be called LED and the light receiving element will be called Ptr. The LED and Ptr are placed inside the housing with their optical axes facing each other, and the light emitted from the LED enters the Ptr straight. If the space between the LED and Ptr is blocked by the light shielding flag, the light will not reach the Ptr, so the presence or absence of the light shielding flag is determined by whether or not light has entered the Ptr.

[0003] In recent years, the mainstream of semiconductor packages has been changing from lead type to surface mount type. Therefore, a transparent photointerrupter using a surface mount type LED and Ptr as shown in Figure 19 has been proposed.

[0004] Figure 11 is composed of a chip LED with its optical axis perpendicular, a chip Ptr with its optical axis perpendicular, and a housing with an internal reflective surface, in which light emitted vertically from the LED is reflected twice by the reflective surface of the housing and enters Ptr from the vertical direction.

[0005] Furthermore, as a method for constructing a transmissive photointerrupter using a surface-mount type element at a lower cost, an inexpensive transmissive photointerrupter configuration using a light guide formed from transparent resin as in Patent Document 1, instead of a housing having an internal reflective surface, can be considered. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent Publication No. 2021-034674 Summary of the Invention [Problem to be solved by the invention]

[0007] In the optical sensor employing the above-mentioned transmissive photointerrupter configuration, there is a demand for an optical sensor that can realize a measure against stray light from the light emitting element to the light receiving element with a reduced cost configuration. [Means for solving the problem]

[0008] In order to achieve the above object, the present invention provides: The optical sensor has a light-emitting element, a light-receiving element that receives light emitted from the light-emitting element, a substrate on which the light-emitting element and the light-receiving element are mounted, and a light-guiding member formed of a transparent resin that is arranged on the surface of the substrate, the light-guiding member having a first portion and a second portion that guide the light emitted from the light-emitting element to the light-receiving element, the first portion and the second portion facing each other across a space, the light emitted from the light-emitting element being guided to exit the first portion and enter the second portion through the space, and the optical sensor detects a detected object when a detected object blocks the light exiting the first portion in the space, the optical sensor being characterized in that the exit portion of the first portion is farther from the light-emitting element than the entrance portion into which light from the light-emitting element of the first portion enters, and the width of the exit portion from which light exits the first portion in a direction perpendicular to both a direction perpendicular to the substrate surface and a direction in which the light emitted from the light-emitting element moves from the first portion to the second portion is smaller than the width of the entrance portion in a direction perpendicular to both of the directions.

[0009] As a means to achieve another goal, The optical sensor has a light-emitting element, a light-receiving element that receives light emitted from the light-emitting element, a substrate on which the light-emitting element and the light-receiving element are mounted, and a light-guiding member formed of a transparent resin that is arranged on the surface of the substrate, the light-guiding member having a first portion and a second portion that guide the light emitted from the light-emitting element to the light-receiving element, the first portion and the second portion facing each other across a space, the light emitted from the light-emitting element is guided to exit the first portion and enter the second portion through the space, and the optical sensor detects a detected object when a detected object blocks the light exiting the first portion in the space, the optical sensor being characterized in that the exit portion of the first portion is farther from the light-emitting element than the entrance portion through which light from the light-emitting element of the first portion enters, and the area from which the light exits the exit portion is lens-shaped so that the luminous flux width of the light emitted from the exit portion narrows as it travels to the second portion.

[0010] As a means to achieve another goal, The optical sensor comprises a light-emitting element, a light-receiving element that receives light emitted from the light-emitting element, a substrate on which the light-emitting element and the light-receiving element are mounted, and a light-guiding member formed of transparent resin that is arranged on the surface of the substrate, the light-guiding member having a first portion and a second portion that guides the light emitted from the light-emitting element to the light-receiving element, the first portion and the second portion facing each other across a space, the light emitted from the light-emitting element is guided to exit the first portion and enter the second portion through the space, and the optical sensor detects a detected object when the detected object blocks the light exiting from the first portion in the space, and is characterized in that at least one of the light-emitting element and the light-receiving element is mounted on the surface opposite to the side on which the light-guiding member is arranged so that the light-guiding member emits light or receives light through an opening provided in the substrate. Effect of the Invention

[0011] As described above, in an optical sensor that employs the above-mentioned transmissive photointerrupter configuration, it is possible to obtain an optical sensor that can realize measures against stray light from the light-emitting element to the light-receiving element with a reduced cost configuration. [Brief description of the drawings]

[0012] [Figure 1] FIG. 2 is a front view of the optical sensor according to the first embodiment. [Diagram 2] 3 is an equivalent circuit of the optical sensor in the first embodiment. [Diagram 3] FIG. 2 is a perspective view of an optical sensor according to the first embodiment. [Figure 4] FIG. 4 is an image diagram of the optical path of light at cross section 1 of FIG. 3 in Example 1. [Diagram 5] FIG. 4 is an output characteristic diagram of the optical sensor in the first embodiment. [Figure 6] FIG. 11 is a perspective view of an optical sensor according to a second embodiment. [Figure 7] FIG. 6 is an image diagram of the optical path of light at cross section 1 of FIG. 5 in Example 2. [Figure 8] FIG. 11 is a perspective view of an optical sensor according to a third embodiment. [Figure 9] FIG. 11 is an image diagram of the optical path of light at cross section 1 of FIG. 8 in Example 3. [Figure 10] FIG. 13 is a front view of a conventional optical sensor. [Figure 11] FIG. 13 is a front view of the optical sensor according to the fourth embodiment. [Figure 12] FIG. 13 is a perspective view of an optical sensor according to a fourth embodiment. [Figure 13] FIG. 13 is a comparison diagram of output characteristics of the optical sensor in the fourth embodiment and the conventional example. [Figure 14] FIG. 13 is a front view of an optical sensor according to a fifth embodiment. [Figure 15] FIG. 13 is a perspective view of an optical sensor according to a fifth embodiment. [Figure 16] FIG. 13 is a front view of an optical sensor according to a sixth embodiment. [Figure 17] FIG. 13 is a perspective view of an optical sensor according to a sixth embodiment. [Figure 18]An example of a conventional optical sensor. [Figure 19] An example of a conventional optical sensor. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] [Example 1] An optical sensor according to a first embodiment of the present invention will be described with reference to FIGS. 1(A) and 1(B). In this embodiment, an LED with a perpendicular optical axis is used as the light-emitting element 101, and a Ptr (phototransistor) with a perpendicular optical axis is used as the light-receiving element 103. In this embodiment, a surface-mount type element capable of being reflow mounted is used. However, it is not limited to the surface-mount type element, and a lead type element may be used. The substrate 104 is a substrate for mounting components, and the light-emitting element 101 and the light-receiving element 103 are mounted side by side on the substrate 104. The light guide 105 formed of a transparent resin is a light-guiding member that guides the light emitted from the light-emitting element 101 in a direction perpendicular to the surface of the substrate 104 to the light-receiving element 103 by internal reflection. As shown in FIGS. 1(A) and 1(B), the light guide 105 has a first portion 201 and a second portion 202 surrounded by a dotted line, and the first portion 201 and the second portion 202 face each other via a spatial gap 110. The light guide 105 is attached to the substrate 104 after the light emitting element 101 and the light receiving element 103 are reflow mounted. FIG. 1A shows a case where there is no light shielding flag (detection object) 111 in the spatial gap 110, and FIG. 1B shows a case where there is a light shielding flag 111 in the spatial gap 110. The solid arrow indicates an optical path in which light emitted from the light emitting element 101 enters the light guide 105 from the entrance portion 203 of the first portion 201, is guided to the exit portion 204 of the first portion 201 by internal reflection, exits from the exit portion 204, and enters the light receiving element 103 by internal reflection. When there is no light shielding flag 111 in the spatial gap 110, as shown by the solid arrow in FIG. 1A, the light entering the light guide 105 from the light emitting element 101 passes through the spatial gap 110 and is guided by internal reflection at the second portion 202 of the light guide 105 to reach the light receiving element 103. When the light-shielding flag 111 is present in the spatial gap 110, as shown by the solid arrow in FIG. 1B, the light incident on the light guide 105 from the light-emitting element 101 is blocked by the light-shielding flag 111 in the spatial gap 110 and does not reach the light-receiving element 103.

[0014] 2 shows an equivalent circuit of the optical sensor and the drive circuit. The anode of the light-emitting element 101 is connected to a DC power supply via a current limiting resistor 114, and the cathode is connected to GND. The collector of the light-receiving element 103 is connected to the power supply via a pull-up resistor 112, and the emitter is connected to GND. The voltage output unit 113 is connected to the collector of Ptr, and indicates the voltage between the collector terminal of Ptr and GND. The voltage output unit 113 outputs L when Ptr is in the ON state where light is incident on it, and outputs H when no light is incident on it in the OFF state.

[0015] The features of this embodiment will be described with reference to FIG. 3 and FIG. 4. FIG. 3 shows a perspective view of FIG. 1. FIG. 4 shows an image of the light path of light in the cross section 1 of FIG. 3. The light shielding flag 111 moves in the -Y direction in the spatial gap. As shown in FIG. 3, this embodiment is characterized in that the Y-direction width d1 of the surface where light enters the light guide 105 from the light emitting element 101 (the width in the direction perpendicular to both the direction perpendicular to the surface of the substrate 104 and the direction in which the light emitted from the light emitting element 101 travels from the first portion 201 to the second portion 202) is larger than the Y-direction width d2 of the surface where the light is emitted from the light guide 105 to the spatial gap 110. The Y-direction width d3 of the surface that refracts the light emitted vertically from the light emitting element 101 in the horizontal direction is equal to d2. The image of the light path in the cross section 1 of FIG. 3 will be described with reference to FIG. 4. The light passing through the spatial gap 110 passes through the spatial gap with the width of the Y-direction width d2 of the light guide. When the light-shielding flag 111 moves a distance d2 in the -Y direction, it changes from a non-light-shielded state to a completely light-shielded state. If the speed at which the light-shielding flag 111 moves in the -Y direction is v, the transition time T required for the light-shielding flag 111 to change from the non-light-shielded state to the completely light-shielded state is determined by equation (1). T=d2 / v formula (1) The transition time T is an important parameter relating to responsiveness.

[0016] The relationship between time T and responsiveness will be described with reference to FIG. 5. The horizontal axis indicates time, and the vertical axis indicates the amount of light incident on the light receiving element 103. The time T determined by the light beam width d and the light shielding flag moving speed v differs depending on whether the light beam width in the spatial gap 110 is large or small. The time T at which the non-light shielding state transitions to the completely light shielding state is T2 when the light beam width is large, and T1 when the light beam width is small. The time from when the light shielding flag 111 starts shielding the light beam to when the amount of light incident on the light receiving element 103 drops to the light shielding flag detection threshold is t1 or t2. From FIG. 5, the smaller the light beam width in the spatial gap 110 is, the shorter the detection delay time of the light shielding flag 111 is, based on the relationship between t1 and t2. Also, from FIG. 5, the variation in the light shielding flag detection threshold is Δt1 or Δt2, which corresponds to the variation in the timing of the light shielding flag detection time. That is, the smaller the light flux width in the spatial gap 110, the smaller the variation in the detection timing for the presence or absence of the light blocking flag 111.

[0017] As described above, in this embodiment, the width of the surface where light from the light emitting element 101 enters the light guide 105 is large, and the refraction surface and the exit surface from the light guide to the spatial gap are narrowed. This makes it possible to efficiently take in the light from the light emitting element 101 into the light guide while narrowing the light flux width in the spatial gap. Therefore, it is possible to provide an optical sensor with good responsiveness and little detection timing error without using a non-transparent resin.

[0018] [Example 2] An optical sensor according to a second embodiment of the present invention will be described with reference to Figs. 6 and 7. Descriptions of the same contents as those in the previous embodiments will be omitted. Fig. 6 shows an image of the optical sensor in this embodiment. The difference from the first embodiment is that the shape of the light guide 105 is partially different. Specifically, as shown in Fig. 7, the shape of the light guide 105 in cross section 1 is trapezoidal.

[0019] As in the first embodiment, the light shielding flag 111 moves in the -Y direction in the spatial gap. In this embodiment, as shown in FIG. 6, the Y direction width d1 of the surface where light enters the light guide 105 from the light emitting element 101 is larger than the Y direction width d2 of the surface where the light is emitted from the light guide 105 to the spatial gap 110. On the other hand, the Y direction width d3 of the surface that refracts the light emitted vertically from the light emitting element 101 to the horizontal direction is longer than d2. By making the Y direction width d3 of the refracting surface larger than that of the first embodiment, more of the light emitted from the light emitting element 101 can be collected in the spatial gap 110. In addition, by partially increasing the thickness of the light guide 105, the effect of ensuring the strength of the light guide 105 can be obtained.

[0020] An image of the light path in cross section 1 in FIG. 6 will be described with reference to FIG. 7. A light ray passing through spatial gap 110 passes through a spatial gap with a width of d2 in the Y direction of the light guide. When light-shielding flag 111 moves a distance d2 in the -Y direction, it changes from a non-light-shielding state to a completely light-shielding state. If the speed at which light-shielding flag 111 moves in the -Y direction is v, the transition time T required to change from a non-light-shielding state to a completely light-shielding state is determined by equation (1). Therefore, the transition time T is equivalent to that of embodiment 1.

[0021] As a result, the present embodiment can achieve the same effects as the first embodiment.

[0022] [Example 3] An optical sensor according to a third embodiment of the present invention will be described with reference to Figs. 8 and 9. Descriptions of the same contents as those in the previous embodiments will be omitted. Fig. 8 shows an image of the optical sensor in this embodiment. A difference from the first embodiment is that the shape of the light guide 105 is partially different. As in the first embodiment, the light shielding flag 111 moves in the spatial gap in the -Y direction.

[0023] In this embodiment, as shown in Fig. 8, the Y-direction width d1 of the surface where light enters the light guide 105 from the light emitting element 101 is greater than the Y-direction width d2 of the surface where the light exits from the light guide 105 to the spatial gap 110. As shown in Fig. 9, the exit surface (the region from which light exits from the exit portion 204) of the light guide 105 that outputs light to the spatial gap 110 in the cross section 1 has a hemispherical shape (lens shape), and the light that has been output to the spatial gap is focused near the entrance surface where the light enters the light guide again from the spatial gap.

[0024] In the first and second embodiments, the width of the exit surface of the light guide 105 to the spatial gap 110 is narrowed to narrow the light beam width. However, in the third embodiment, the exit surface is made to have a hemispherical lens shape to condense the light, thereby narrowing the light beam width. An image of the light path in the cross section 1 of FIG. 8 will be described with reference to FIG. 9. The light passing through the spatial gap 110 is condensed by the lens shape when it is emitted to the spatial gap 110 with a width of d2 in the Y direction of the light guide 105, and the light beam width becomes d4 at the detection position of the light shielding flag 111 in the X direction. When the light shielding flag 111 moves a distance d4 in the -Y direction, it goes from a non-light shielding state to a completely light shielding state. If the speed at which the light shielding flag 111 moves in the -Y direction is v, the transition time T required for the light shielding flag 111 to go from a non-light shielding state to a completely light shielding state is determined by the formula (2). T=d4 / v Equation (2) If d4 is set to a length equivalent to d2 in the first and second embodiments, the transition time T will be approximately the same as in the first embodiment.

[0025] As described above, in this embodiment, the surface through which light incident from the light emitting element 101 into the light guide 105 is emitted to the spatial gap 110 is made to have a hemispherical lens shape. This makes it possible to narrow the light flux width at the detection position of the light-shielding flag 111 in the X direction by concentrating the light emitted from the light guide 105. In addition, concentrating the light makes it possible to improve the transmission efficiency of light that reaches the light receiving element 103 from the light emitting element 101 when the light is not blocked. By improving the transmission efficiency of the light emitting element 101 and the light receiving element 103, it becomes possible to use elements that emit less light, thereby reducing component costs and saving power.

[0026] [Example 4] An optical sensor according to a fourth embodiment of the present invention will be described. The same contents as those of the above-mentioned embodiment will not be described. First, the problems in the conventional example will be described with reference to FIG. 10. The light emitting element 101 uses a surface mount type LED with a vertical optical axis that can be mounted by reflow, and the light receiving element 103 uses a Ptr (phototransistor) with a vertical optical axis. As shown in FIG. 10, the light emitting element 101 and the light receiving element 103 are mounted side by side on the substrate 104. The light guide 105 formed of transparent resin guides the light emitted in the vertical direction from the light emitting element 101 to the light receiving element 103 by internal reflection. The light guide 105 is attached to the substrate 104 after the light emitting element 101 and the light receiving element 103 are mounted on the substrate 104 by reflow. The solid line arrow indicates an optical path in which the light emitted in the vertical direction from the light emitting element 101 is guided to pass through the spatial gap 110 by internal reflection of the light guide, and the light that enters the light guide 105 again is guided to enter the light receiving element 103. The dotted arrow indicates the optical path of light emitted horizontally from the light-emitting element 101, which enters the light-receiving element 103 as stray light. If there is a light-shielding flag 111 in the spatial gap 110, the optical path is blocked, and the amount of light vertically incident on the light-receiving element 103 is reduced. Light passing through the optical path indicated by the dotted arrow is incident on the light-receiving element 103 horizontally, regardless of the presence or absence of the light-shielding flag 111. The optical sensor determines whether or not there is a light-shielding flag 111 in the spatial gap 110 based on changes in the amount of light entering the light-receiving element 103, and therefore, if there is stray light, it is not possible to accurately detect the presence or absence of the light-shielding flag 111.

[0027] FIG. 11 shows a front view of this embodiment, and FIG. 12 shows a perspective view. In this embodiment, in order to eliminate the influence of the stray light, unlike FIG. 10 of the conventional example, the light emitting element 101 and the light receiving element 103 are mounted on the surface opposite to the side where the light guide 105 is located on the substrate 104, as shown in FIG. 11 and FIG. 12. The light emitting element 101 and the light receiving element 103 are used as the LED with the optical axis perpendicular and the Ptr (phototransistor) with the optical axis perpendicular, which are rear-mount type elements that can be reflow mounted. The light emitting element 101 and the light receiving element 103 are mounted on the surface opposite to the surface where the light guide 105 is attached, so as to be fitted into the opening on the substrate 104. The light emitted vertically from the light emitting element 101 enters the light guide through the opening of the substrate 104, and the light emitted from the light guide is guided by the internal reflection of the light guide and enters the light receiving element 103 through the opening of the substrate 104. However, the light emitting element 101 and the light receiving element 103 are not limited to the surface mounting type, and a lead type may be used. 11, the light emitted horizontally from the light emitting element 101 is attenuated by the inner wall of the substrate 104. That is, the substrate 104 existing between the light emitting element 101 and the light receiving element 103 functions as a shield for blocking stray light, so that the influence of the stray light due to the light emitted horizontally can be prevented.

[0028] As described above, by mounting the light emitting element 101 and the light receiving element 103 on the surface opposite to the surface on which the light guide 105 is attached, so as to be fitted into the opening in the substrate 104, it is possible to provide an optical sensor that is less susceptible to the effects of stray light. The output characteristics of the optical sensor in this embodiment are shown in FIG. 13.

[0029] The horizontal axis indicates the current flowing through the light emitting element 101, and the vertical axis indicates the voltage of the voltage output unit 113. The amount of light emitted by the light emitting element 101 is proportional to the current flowing. (In the experiment, the DC input voltage was 3.3V, and the LED used was a rated 50mA product.) The voltage of the voltage output unit 113 is connected to a logic IC, and is compared with a reference voltage inside the logic IC to be determined as two values, H output and L output. For example, a logic IC that operates with an input of 3.3V recognizes 2.6V or more as H output and 0.6V or less as L output, and cannot correctly recognize H and L between 0.6V and 2.6V. The amount of light emitted by the light emitting element 101 changes depending on the ambient temperature, the accumulated lighting time, the light emitting efficiency of the light emitting element 101, and the optical axis. The light receiving sensitivity characteristic of the light receiving element 103 changes depending on the ambient temperature, the Ptr sensitivity, and the variation in the internal reflectance of the clear mold. In the experiment, the current flowing through the light emitting element 101 was changed to confirm the influence of the variation.

[0030] In FIG. 13, the solid line data indicates the output when there is no light shielding flag in the spatial gap 110 and the influence of stray light is removed. The dashed line data indicates the output when there is a light shielding flag in the spatial gap 110 and the influence of stray light is present. The dotted line data indicates the output when there is a light shielding flag in the spatial gap 110 and the influence of stray light is removed. The solid line data is an L output independent of the current flowing through the light-emitting element 101, so it can be said that it is possible to determine whether there is a light shielding flag. The dashed line data is an H output independent of the current flowing through the light-emitting element 101, so it cannot be said that there is a light shielding flag. The dotted line data is an H output independent of the current flowing through the light-emitting element 101, so it can be said that there is a light shielding flag. As described above, if there is an influence of stray light, it is indispensable to remove the influence of stray light because the optical sensor cannot determine whether there is a light shielding flag.

[0031] [Example 5] An optical sensor according to a fifth embodiment of the present invention will be described with reference to Figs. 14 and 15. The same contents as those of the above-mentioned embodiments will not be described. Fig. 14 shows a front view of this embodiment, and Fig. 15 shows a perspective view. The fifth embodiment is different from the fourth embodiment in that a copper through hole 106 is provided between the light emitting element 101 and the light receiving element 103 on the substrate 104. Although it depends on the material of the substrate 104, the inner layer of a general paper phenol substrate or a glass epoxy resin substrate is not completely non-transparent. Therefore, as described in the fourth embodiment, although the substrate 104 existing between the light emitting element 101 and the light receiving element 103 blocks and attenuates stray light, the light receiving element 103 may receive stray light depending on the amount of light emitted from the light emitting element 101.

[0032] Therefore, by providing a copper through hole 106 on the optical path of the stray light as in this embodiment, the stray light can be completely blocked because copper does not transmit light. A plurality of copper through holes 106 may be provided as necessary. Furthermore, the through hole 106 is not limited to copper, and any non-transparent material may be used. As described above, the light emitting element and the light receiving element 103 are mounted on the surface opposite to the surface on which the light guide 105 is attached by fitting them into the openings on the substrate 104. Furthermore, by providing the copper through hole 106 between the light emitting element 101 and the light receiving element 103, it is possible to provide an optical sensor that is not affected by stray light.

[0033] [Example 6] An optical sensor according to a sixth embodiment of the present invention will be described with reference to Figs. 16 and 17. The same contents as those of the above-mentioned embodiments will not be described. Fig. 16 shows a front view of this embodiment, and Fig. 17 shows a perspective view. In this embodiment, in order to eliminate the influence of the stray light, as shown in Figs. 16 and 17, only the light emitting element 101 is mounted on the surface opposite to the side on the substrate 104 on which the light guide 105 is arranged. This embodiment is not limited to this, and only the light receiving element 103 may be mounted on the surface opposite to the side on the substrate 104 on which the light guide 105 is arranged. In other words, including the fourth embodiment, at least one of the light emitting element 101 and the light receiving element 103 may be mounted on the surface opposite to the side on which the light guide 105 is arranged. The light emitting element 101 is mounted on the substrate 104 on the surface opposite to the surface on which the light guide 105 is attached, so as to be fitted into an opening on the substrate 104. Light emitted vertically from the light-emitting element 101 passes through an opening in the substrate 104 and enters the light guide. The light is guided by internal reflection of the light guide and exits from the light guide, and enters the light-receiving element 103.

[0034] Since the light emitting element 101 and the light receiving element 103 are mounted at different positions in the direction perpendicular to the optical axis, it is possible to prevent light emitted in the horizontal direction from the light emitting element 101 from entering the light receiving element 103 as stray light. The light emitting element 101 and the light receiving element 103 are not limited to the surface mounting type, and a lead type may also be used.

[0035] As described above, by mounting only the light-emitting element in an opening on the substrate 104 on the side opposite to the side on which the light guide 105 is attached and the side on which the light-receiving element 103 is mounted, it is possible to provide an optical sensor that is not affected by stray light.

[0036] The contents of each of the first to sixth embodiments may be combined. For example, the contents of the fourth to sixth embodiments, in which at least one of the light emitting element 101 and the light receiving element 103 is mounted on the surface opposite to the side where the light guide 105 is disposed, may be combined with the contents of the first to third embodiments, in which the width and shape of the emission part 204 are devised.

[0037] [Note] The above embodiments disclose at least the following optical sensors.

[0038] (Item 1) A light-emitting element; a light receiving element that receives light emitted from the light emitting element; a substrate on which the light emitting element and the light receiving element are mounted; a light guiding member formed of a transparent resin and disposed on a surface of the substrate, the light guiding member having a first portion and a second portion for guiding the light emitted from the light emitting element to the light receiving element; The first portion and the second portion face each other across a space, The light emitted from the light emitting element is guided so as to exit the first portion and enter the second portion through the space, An optical sensor that detects a detection object by blocking light emitted from the first portion in the space, An optical sensor characterized in that an exit portion of the first portion is farther from the light-emitting element than an entrance portion through which light from the light-emitting element of the first portion enters, and the width of the exit portion from which light exits the first portion in a direction perpendicular to both a direction perpendicular to the surface of the substrate and a direction in which light emitted from the light-emitting element travels from the first portion to the second portion is smaller than the width of the entrance portion in a direction perpendicular to both of the directions.

[0039] (Item 2) Item 1, an optical sensor according to the present invention, the first portion reflects the light emitted from the light emitting element to cause the light to enter the second portion from the emission portion through the space; An optical sensor, characterized in that, when viewed from the surface of the substrate, the emission portion and the reflecting position are spaced apart by the same distance.

[0040] (Item 3) A light-emitting element; a light receiving element that receives light emitted from the light emitting element; a substrate on which the light emitting element and the light receiving element are mounted; a light guiding member formed of a transparent resin and disposed on a surface of the substrate, the light guiding member having a first portion and a second portion for guiding the light emitted from the light emitting element to the light receiving element; The first portion and the second portion face each other across a space, The light emitted from the light emitting element is guided so as to exit the first portion and enter the second portion through the space, An optical sensor that detects a detection object by blocking light emitted from the first portion in the space, An optical sensor characterized in that an exit portion of the first portion is farther from the light-emitting element than an entrance portion through which light enters from the light-emitting element of the first portion, and the area through which light exits the exit portion is lens-shaped so that the light flux width of the light emitted from the exit portion narrows as it travels toward the second portion.

[0041] (Item 4) Item 3. The optical sensor according to item 3, the first portion reflects the light emitted from the light emitting element to cause the light to enter the second portion from the emission portion through the space; An optical sensor, characterized in that, when viewed from the surface of the substrate, the emission portion and the reflecting position are spaced apart by the same distance.

[0042] (Item 5) A light-emitting element; a light receiving element that receives light emitted from the light emitting element; a substrate on which the light emitting element and the light receiving element are mounted; a light guiding member formed of a transparent resin and disposed on a surface of the substrate, the light guiding member having a first portion and a second portion for guiding the light emitted from the light emitting element to the light receiving element; The first portion and the second portion face each other across a space, The light emitted from the light emitting element is guided so as to exit the first portion and enter the second portion through the space, An optical sensor that detects a detection object by blocking light emitted from the first portion in the space, An optical sensor characterized in that at least one of the light-emitting element and the light-receiving element is mounted on a surface opposite to the side on which the light-guiding member is arranged so that at least one of the light-emitting element and the light-receiving element emits light or receives light through an opening provided in the substrate.

[0043] (Item 6) Item 6. The optical sensor according to item 5, An optical sensor, characterized in that at least one of the light emitting element and the light receiving element is mounted on the substrate so that the light emitting element and / or the light receiving element is disposed within the opening.

[0044] (Item 7) 7. The optical sensor according to items 5 to 6, An optical sensor comprising: a through hole provided on said substrate at a position between said light emitting element and said light receiving element, said through hole being arranged in a direction perpendicular to a surface of said substrate.

[0045] (Item 8) 8. The optical sensor according to items 5 to 7, The optical sensor is characterized in that the light guiding member is made of a transparent resin.

[0046] (Item 9) Item 9. The optical sensor according to item 8, An optical sensor characterized in that an exit portion of the first portion is farther from the light-emitting element than an entrance portion through which light from the light-emitting element of the first portion enters, and the width of the exit portion from which light exits the first portion in a direction perpendicular to both a direction perpendicular to the surface of the substrate and a direction in which light emitted from the light-emitting element travels from the first portion to the second portion is smaller than the width of the entrance portion in a direction perpendicular to both of the directions.

[0047] (Item 10) Item 9. The optical sensor according to item 8, 9. The optical sensor described in item 8, characterized in that the exit section of the first section is farther from the light emitting element than the entrance section through which light from the light emitting element of the first section enters, and the exit section has a lens shape so that the light flux width of the light emitted from the exit section through which light leaves the first section narrows as it travels to the second section. [Explanation of symbols]

[0048] 101 Light emitting element 103 Photodetector 104 Substrate 105 Light Guide 110 Spatial Gap

Claims

1. A light-emitting element; a light receiving element that receives light emitted from the light emitting element; a substrate on which the light emitting element and the light receiving element are mounted; a light guiding member formed of a transparent resin and disposed on a surface of the substrate, the light guiding member having a first portion and a second portion for guiding the light emitted from the light emitting element to the light receiving element; The first portion and the second portion face each other across a space, The light emitted from the light-emitting element is guided so as to exit the first portion and enter the second portion through the space, An optical sensor that detects an object by blocking light emitted from the first portion in the space, An optical sensor characterized in that an exit portion of the first portion is farther from the light-emitting element than an entrance portion into which light from the light-emitting element of the first portion enters, and the width of the exit portion from which light exits the first portion in a direction perpendicular to both a direction perpendicular to the surface of the substrate and a direction in which light emitted from the light-emitting element travels from the first portion to the second portion is smaller than the width of the entrance portion in a direction perpendicular to both of the directions.

2. the first portion reflects the light emitted from the light-emitting element to cause the light to enter the second portion from the emission portion through the space; 2. The optical sensor according to claim 1, wherein the emission portion and the position where the light is reflected are spaced apart by the same distance when viewed from the surface of the substrate.

3. A light-emitting element; a light receiving element that receives light emitted from the light emitting element; a substrate on which the light emitting element and the light receiving element are mounted; a light guiding member formed of a transparent resin and disposed on a surface of the substrate, the light guiding member having a first portion and a second portion for guiding the light emitted from the light emitting element to the light receiving element; The first portion and the second portion face each other across a space, The light emitted from the light-emitting element is guided so as to exit the first portion and enter the second portion through the space, An optical sensor that detects an object by blocking light emitted from the first portion in the space, An optical sensor characterized in that an exit portion of the first portion is farther from the light-emitting element than an entrance portion where light from the light-emitting element of the first portion enters, and the area from which light exits the exit portion is lens-shaped so that the light flux width of the light emitted from the exit portion narrows as it travels toward the second portion.

4. the first portion reflects the light emitted from the light-emitting element to cause the light to enter the second portion from the emission portion through the space; 4. The optical sensor according to claim 3, wherein the emission portion and the reflecting position are spaced apart by the same distance when viewed from the surface of the substrate.

5. A light-emitting element; a light receiving element that receives light emitted from the light emitting element; a substrate on which the light emitting element and the light receiving element are mounted; a light guiding member formed of a transparent resin and disposed on a surface of the substrate, the light guiding member having a first portion and a second portion for guiding the light emitted from the light emitting element to the light receiving element; The first portion and the second portion face each other across a space, The light emitted from the light-emitting element is guided so as to exit the first portion and enter the second portion through the space, An optical sensor that detects an object by blocking light emitted from the first portion in the space, An optical sensor characterized in that at least one of the light-emitting element and the light-receiving element is mounted on a surface opposite to the side on which the light-guiding member is arranged so that at least one of the light-emitting element and the light-receiving element emits light or receives light through an opening provided in the substrate.

6. 6. The optical sensor according to claim 5, wherein at least one of the light emitting element and the light receiving element is mounted on the substrate so that the at least one of the light emitting element and the light receiving element is disposed within the opening.

7. 6. The optical sensor according to claim 5, further comprising a through hole extending perpendicularly to the surface of the substrate at a position between the light emitting element and the light receiving element on the substrate.

8. The optical sensor according to claim 5 , wherein the light guide member is made of a transparent resin.

9. The optical sensor described in claim 8, characterized in that the exit portion of the first portion is farther from the light-emitting element than the entrance portion through which light from the light-emitting element of the first portion enters, and the width of the exit portion from which light exits the first portion in a direction perpendicular to both a direction perpendicular to the surface of the substrate and a direction in which light emitted from the light-emitting element travels from the first portion to the second portion is smaller than the width of the entrance portion in a direction perpendicular to both of the directions.

10. 9. The optical sensor according to claim 8, wherein the exit portion of the first portion is farther from the light-emitting element than the entrance portion through which light from the light-emitting element of the first portion enters, and the exit portion has a lens shape such that the light beam width of the light emitted from the exit portion through which light leaves the first portion narrows as it travels toward the second portion.

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