JP7434776B2 - Guided light sensor, collision prevention system and mobile information terminal - Google Patents

Description

The present invention relates to a guided optical sensor, a collision prevention system, and a mobile information terminal.

Conventionally, when users of mobile information terminals such as smartphones perform ``walking smartphone'', which involves walking while looking at the screen, this is to prevent users of mobile information terminals from colliding with other pedestrians or obstacles. devices, systems and programs have been invented.

Patent Document 1 discloses a system that uses a position detection device such as a GPS (Global Positioning System) to calculate the distance between the user's smartphone and surrounding terminal users, and presents the risk of collision to the user via the smartphone. Collision prevention devices, etc. are described.

Patent Document 2 describes a method that uses a LIDAR (Light Detection and Ranging) element to measure the distance and direction between a smartphone user and an object in front, and presents the risk of collision to the user via the smartphone. A hazard avoidance support program is described.

Unexamined Japanese Patent Publication No. 2018-160002 JP2017-183787A

The collision prevention device described in Patent Document 1 uses GPS and the like, and cannot present the risk of collision with a non-user of a terminal such as a smartphone that cannot be recognized by GPS or the like.

In order to make the danger avoidance support program effective, the danger avoidance support program described in Patent Document 2 requires that the back of the smartphone be tilted downward due to the limit of the measurement range of the LIDAR element provided on the back of the smartphone. If the angle exceeds 1/2 of the angle of view of the LIDAR element, measurement in the horizontal direction becomes impossible.

In view of the above circumstances, the present invention is capable of detecting the risk of collision from the front, including from people other than the mobile information terminal user, when using the smartphone while walking, and the sensor installation surface is facing vertically downward. Another object of the present invention is to provide a guided optical sensor, a collision prevention system, and a mobile information terminal that can detect the risk of a collision from the front.

A light sensor with a guide according to the present invention includes a light emitting element that emits a light beam when a voltage is applied thereto, a light guide section that changes the traveling direction of the light beam emitted from the light emitting element, and a light guide section that changes the traveling direction of the light beam that is emitted from the light guide section and hits an object. a light-receiving element that receives the reflected light beam and generates a voltage, and the light guide section has a half that diffuses the light beam emitted from the light guide section and does not transmit the light beam that hits an object and is reflected. The present invention is characterized by comprising a diffuser plate with a mirror, and a condensing section for changing the traveling direction of the light beam emitted from the light guide section, hitting an object and reflecting, and guiding the light beam to the light receiving element .

The collision prevention system of the present invention includes a plurality of the guided light sensors, a partition section that separates a range in which the light beam is emitted for each of the plurality of guided light sensors, a control section, and an acceleration sensor, The control unit includes a display unit, a determination unit that determines whether the display unit is activated or stopped, receives a signal corresponding to the magnitude of acceleration from the acceleration sensor, receives a determination result from the determination unit, and controls the display unit. a permission unit that permits the application of voltage to the light emitting element only when the light emitting element is activated and the acceleration is greater than a specified value; and a permission unit that applies voltage to the light emitting element at regular time intervals so that the light receiving element emits light. a voltage processing unit that detects voltage and specifies the distance to the object; a storage unit that stores the distance to the object specified by the voltage processing unit; and a storage unit that stores the distance to the object stored in the storage unit and the distance to the object. a calculation unit that determines whether the object has approached based on the result of comparing the distance to the object after a certain time interval and whether the distance to the object after the certain time interval is less than a certain value; and an alarm unit that displays an alarm on the display unit when a determination that the object approaches is received from the calculation unit.

A portable information terminal according to the present invention is characterized by comprising the collision prevention system described above.

The optical sensor with guide, the collision prevention system, and the mobile information terminal of the present invention are capable of detecting the risk of collision from the front, including those other than the user of the mobile information terminal, when "walking with a smartphone". Even if the surface is facing vertically downward, it is possible to detect the risk of a collision from the front.

FIG. 1 is a sectional view showing a guided optical sensor according to a first embodiment of the present invention. FIG. 3 is a cross-sectional view showing the guided optical sensor when emitting light. FIG. 3 is a cross-sectional view showing the optical sensor with a guide when a light beam enters the sensor. It is a figure which shows the case where the same optical sensor with a guide is mounted in a portable information terminal. FIG. 2 is a configuration diagram showing a collision prevention system according to a second embodiment of the present invention. It is a flowchart showing a processing procedure for the same collision prevention system to detect the risk of collision and display a warning. FIG. 3 is a diagram showing a display section of the collision prevention system. FIG. 3 is a diagram showing a display section when the collision prevention system detects a risk of collision. FIG. 3 is a sectional view showing a guided optical sensor according to a third embodiment of the present invention. FIG. 3 is a cross-sectional view showing the guided optical sensor when emitting light. FIG. 3 is a cross-sectional view showing the optical sensor with a guide when a light beam enters the sensor. It is a sectional view showing a modified example of the optical sensor with a guide according to the first embodiment of the present invention when a light beam is incident. It is a sectional view showing the same modified example when a light beam enters.

Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. 1 to 4.
FIG. 1 is a sectional view of a guided optical sensor 1 according to this embodiment. The guided optical sensor 1 includes an optical sensor 2 and a light guide section 3. The guided optical sensor 1 is a device that emits a light ray Ra, detects the light ray Ra reflected by hitting an object, specifies the distance to the object, and detects the risk of collision with the object.

Here, the direction in which the optical sensor 2 emits the light ray Ra is referred to as the downward direction in the vertical direction, and the direction from a part of the light guide section 3 from a part close to the optical sensor 2 to a part far from the optical sensor 2 is referred to as a forward direction, an up-down direction, and a front-rear direction. The orthogonal directions are defined as left and right directions. As shown in FIG. 1, the direction of arrow U is the upward direction in the vertical direction, and the direction of arrow D is the downward direction in the vertical direction. The direction of arrow F is the front direction in the front-rear direction, and the direction of arrow B is the rear direction in the front-rear direction. The direction of arrow R is the right direction in the left-right direction, and the direction of arrow L is the left direction in the left-right direction.

The optical sensor 2 includes a light emitting element 21 and a light receiving element 22. The light emitting element 21 is an element that emits a light beam Ra when a voltage is applied thereto, and a known LED or the like is used. The light receiving element 22 is an element that generates a voltage upon receiving the light beam Ra, and a known photodiode or the like is used.

The light guide section 3 is provided below the optical sensor 2, has a substantially rectangular parallelepiped shape, receives the light ray Ra emitted from the optical sensor 2, and changes the traveling direction of the light ray Ra. The light guide section 3 includes a prism 31, a diffusion plate 32 with a half mirror, a light condensing section 33, and a base material layer 34.

The prism 31 has a corner cube shape in this embodiment. A plurality of prisms 31 are arranged using the base material layer 34 as a base. A first array section 31A of prisms 31 is formed below the light guide section 3 along the front-rear direction, and a second array section 31B of prisms 31 is formed above the light guide section 3 along the front-rear direction. .

In the first arrangement section 31A, the plurality of prisms 31 are arranged from near the optical sensor 2 toward the front. The delivery prism 31F located at the frontmost position has a delivery surface IF that is tilted forward and upward and faces the diffuser plate 32 with a half mirror. The other prisms 31 have an input/output surface PF facing upward, a first reflective surface FF located at the rear and tilted with respect to the vertical direction, and a second reflective surface SF located in front and tilted with respect to the vertical direction. , has. The prism 31 further has a third reflective surface (not shown), and the first reflective surface FF, the second reflective surface SF, and the third reflective surface are orthogonal to each other. The prism 31 closest to the optical sensor 2 is arranged so that the first reflective surface FF is located directly below the optical sensor 2.

In the second arrangement section 31B, the plurality of prisms 31 are arranged from near the optical sensor 2 toward the front. Each prism 31 has an input/output surface PF facing downward, a first reflective surface FF located at the rear and tilted with respect to the vertical direction, and a second reflective surface SF located in front and tilted with respect to the vertical direction. has. The prism 31 further has a third reflective surface (not shown), and the first reflective surface FF, the second reflective surface SF, and the third reflective surface are orthogonal to each other. Further, the prism 31 closest to the optical sensor 2 is arranged so as not to overlap between the optical sensor 2 and the prism 31 closest to the optical sensor 2 in the first arrangement section 31A.

Further, the center of the two adjacent prisms 31 of the first array section 31A and the side between the first reflective surface FF and the second reflective surface SF of each prism 31 of the second array section 31B are in the front-rear direction. are placed in the same position.

The half-mirror-equipped diffuser plate 32 has a disk-like shape and is arranged at the center of the front end of the light guide section 3 in the vertical direction. The half-mirror-equipped diffuser plate 32 includes a diffuser plate 32S and a reflective film 32R. As the diffuser plate 32S, a sheet material, a film material, a paper material, or the like that has light transmittance and has a roughened surface can be used. The reflective film 32R is provided behind the diffuser plate 32S. The half-mirror-equipped diffuser plate 32 allows the light rays Ra traveling from the rear to the front to pass through, and does not transmit the light rays Ra traveling from the front to the rear due to the reflective film 32R.

The light condensing section 33 is arranged at the front end of the light guide section 3 in the vertical direction. The light condensing section 33 is a lens having a convex shape toward the front or the rear, preferably a lens having a convex shape toward the front, and in this embodiment is a known Fresnel lens.

The base material layer 34 is made of a light-transmissive material such as a resin material, and serves as a base on which the prism 31, the diffuser plate 32 with a half mirror, and the light condensing section 33 are arranged.

Next, a method for detecting the risk of collision with an object using the guided optical sensor 1 will be described.

The user first applies a voltage to the light emitting element 21 of the optical sensor 2 using an appropriate method. As shown in FIG. 2, the light emitting element 21 to which a voltage is applied emits a light ray Ra toward the rearmost prism 31 of the first arrangement section 31A of the light guide section 3.

The rearmost prism 31 of the first arrangement section 31A allows the light ray Ra to proceed straight on the input/output surface PF, and reflects the light ray Ra received on the first reflection surface FF in the forward direction, and impinges on the second reflection surface SF. The light ray Ra received by the second reflecting surface SF is reflected upward, the light ray Ra emitted from the light input/output surface PF is made to proceed straight, and the light ray Ra is emitted toward the rearmost prism 31 of the second arrangement section 31B. Note that although the third reflecting surface described above may also be involved in the reflection of the light ray Ra, the explanation thereof will be omitted for the sake of brevity.

The rearmost prism 31 of the second arrangement section 31B allows the light ray Ra to travel straight on the input/output surface PF, and reflects the light ray Ra received on the first reflection surface FF in the forward direction, and impinges on the second reflection surface SF. The light ray Ra received by the second reflecting surface SF is reflected downward, the light ray Ra emitted from the light input/output surface PF is made to proceed straight, and the light ray Ra is emitted toward the rearmost prism 31 of the first arrangement section 31A.

Thereafter, such retroreflection is repeated by the first array section 31A and the second array section 31B, and the light ray Ra is advanced forward of the light guide section 3 and reaches the delivery surface IF of the delivery prism 31F of the first arrangement section 31A. guess.

The delivery prism 31F of the first array section 31A reflects the light ray Ra forward and upward, and causes it to advance toward the half mirror-equipped diffuser plate 32.

The half-mirror-equipped diffuser plate 32 receives the light ray Ra, diffuses the light ray Ra over a wide range in front, and emits it from the light guide section 3 .

As shown in FIG. 3, a part of the light ray Ra emitted from the light guide section 3, diffused over a wide range, and reflected by hitting an object enters the condensing section 33. The condensing section 33 receives a part of the light ray Ra, refracts it, and applies it to the delivery surface IF of the delivery prism 31F of the first arrangement section 31A.

The delivery prism 31F of the first arrangement section 31A reflects the light beam Ra upward toward the frontmost prism 31 of the second arrangement section 31B.

The most forward prism 31 of the second array section 31B causes the light ray Ra to travel straight on the input/output surface PF, and reflects the light ray Ra received on the second reflection surface SF in the rear direction, and hits the first reflection surface FF. The light ray Ra received by the first reflecting surface FF is reflected downward, the light ray Ra emitted from the light input/output surface PF is made to proceed straight, and the light ray Ra is emitted toward the prism 31 of the first arrangement section 31A.

The prism 31 of the first arrangement section 31A allows the light ray Ra to proceed straight on the light input/output surface PF, and reflects the light ray Ra received on the second reflection surface SF in the rear direction, so that the reflected light ray hits the first reflection surface FF. The light ray Ra received by the first reflecting surface FF is reflected upward, the light ray Ra emitted from the light input/output surface PF is made to proceed straight, and the light ray Ra is emitted toward the prism 31 of the second arrangement section 31B.

Thereafter, such retroreflection is repeated in the first arrangement section 31A and the second arrangement section 31B, and the light ray Ra is advanced to the rear of the light guide section 3, and is sent from the rearmost prism 31 of the first arrangement section 31A to the light receiving element. Release towards 22.

The light receiving element 22 receives the light ray Ra and generates a voltage. By measuring the voltage generated in the light receiving element 22 using an appropriate method, the user determines the distance to the object in front and detects the risk of collision with the object.

The guided optical sensor 1 of this embodiment, which is configured and operated as described above, illuminates an object with the light ray Ra emitted from the guided optical sensor 1 and receives the reflected light Ra, thereby preventing collision with the object. In order to detect the danger of a collision from the front, it is possible to detect the danger of a collision from the front, including from people other than the user of the mobile information terminal. Furthermore, even when the light ray Ra is emitted vertically downward from the optical sensor 2, the light guide section 3 can change the traveling direction of the light ray Ra and emit it over a wide area in front of the sensor. Even if the installation surface is facing vertically downward, it is possible to detect the risk of a collision from the front.

For example, the guided optical sensor 1 of this embodiment can be used by being attached to a mobile information terminal MT as shown in FIG. The guided optical sensor 1 mounted on the back surface BF of the mobile information terminal MT emits a light ray Ra toward the front FW in the horizontal direction and receives the light ray Ra reflected by hitting an object, even if the back surface BF faces vertically downward VD. By doing so, the distance to the object in the front FW in the horizontal direction can be specified.

Next, a second embodiment of the present invention will be described with reference to FIGS. 5 to 8.
FIG. 5 is a configuration diagram of the collision prevention system 7 according to this embodiment. The collision prevention system 7 includes a sensor unit 4, a control section 5, and an acceleration sensor 6. The collision prevention system 7 is implemented, for example, in a mobile information terminal having a display device, and when the user of the mobile information terminal is considered to be viewing the display device while moving and not visually checking the direction of movement, the collision prevention system 7 This system detects the risk of collision with objects in the direction of movement and presents the danger to the user.

The sensor unit 4 is a combination of a plurality of guided optical sensors 1 of the first embodiment. The sensor unit 4 includes a black, plate-shaped partition 41 at the front between the plurality of guided optical sensors 1 . The plate surface of the partition portion 41 has a constant inclination with respect to the front-rear direction of the optical sensor 1 with a guide. The sensor unit 4 is fixed to the back surface of the mobile information terminal, etc., so that the front of each guided optical sensor 1 faces the direction in which the user of the mobile information terminal moves. By providing the partition portion 41, the range in which the light ray Ra is emitted from each guided optical sensor 1 is divided, and the light ray Ra is received by the guided optical sensor 1 from which the light ray Ra is emitted.

The control section 5 includes a display section 51, a determination section 52, a permission section 53, a voltage processing section 54, a storage section 55, a calculation section 56, and an alarm section 57.

The control unit 5 is a processing device capable of executing programs, which includes a processor (not shown), a memory capable of reading programs, a storage device capable of storing programs and data, an input/output device, and other dedicated hardware. including. The functions of the collision prevention system 7 are realized by a processor executing a program provided to the control unit 5.

The display unit 51 is, for example, a liquid crystal display or an organic EL (Electro Luminescence) display. The display section 51 communicates with the alarm section 57, and displays an alarm in the alarm display area 51A in response to a request from the alarm section 57. Although not shown, the display section 51 communicates with a storage section 55 and a calculation section 56, and also serves as a display device of a portable information terminal, and is capable of displaying various information.

The determination unit 52 communicates with the display unit 51, determines whether the display unit 51 is displaying or not, and transmits the determination result to the permission unit 53.

The permission unit 53 acquires the determination result of whether the display unit 51 is displaying or not from the determination unit 52, acquires the acceleration value from the acceleration sensor 6, and determines whether the display unit 51 is displaying or not. If the value exceeds the specified value, the voltage processing unit 54 and alarm unit 57 are permitted to operate.

When the operation is permitted by the permission unit 53, the voltage processing unit 54 applies a predetermined voltage to the light emitting element 21 of each guided optical sensor 1 of the sensor unit 4 at very short fixed time intervals, and receives light. The voltage occurring in the element 22 is measured.

The voltage processing unit 54 uses the well-known TOF (Time of Flight) method to specify the distance between each guided light sensor 1 and the object based on the measurement result of the voltage generated in the light receiving element 22, and determines the distance between each guided light sensor 1 and the object. Information on the distance between the sensor 1 and the object is transmitted to the storage section.

The storage unit 55 stores information about the distance between the guided optical sensor 1 and the object, which is received from the voltage processing unit 54 .

The calculation unit 56 refers to the information on the distance between the guided optical sensor 1 and the object stored in the storage unit 55, and determines that the distance between the guided optical sensor 1 and the object is approaching and that the guided optical sensor 1 It is determined whether the distance between the object and the object is less than a certain value, and the result is transmitted to the alarm section 57.

The alarm unit 57 is permitted to operate by the permission unit 53, and is notified by the calculation unit 56 that the distance between the guided optical sensor 1 and the object is approaching and the distance between the guided optical sensor 1 and the object is below a certain level. When the determination is obtained, the display section 51 is requested to display a warning.

The acceleration sensor 6 is provided so as to be fixed in position relative to the sensor unit 4, and detects the walking of the user of the mobile information terminal fixed to the sensor unit 4.

FIG. 6 is a flowchart showing the operation of the collision prevention system 7. In step S1, the control unit 5 determines whether the display unit 51 is displaying information. If the display unit 51 is displaying, it is considered that the user is visually viewing the display unit 51, so the control unit 5 proceeds to step S2 below in order to determine whether or not an alarm display is necessary. If the display section 51 is not displaying, the control section 5 determines that the user is not viewing the display section 51, and the operation is completed.

In step S2, the control unit 5 determines whether the acceleration detected by the acceleration sensor 6 exceeds a specified value. If the acceleration exceeds the specified value, it is considered that the user is walking, so the control unit 5 proceeds to step S3 below to determine whether or not an alarm display is necessary. If the acceleration does not exceed the specified value, the control unit 5 determines that the user is not walking, and proceeds to step S4.

In step S4, the control section 5 stops the alarm on the display section 51 when there is a possibility that an alarm is displayed on the display section 51 and the alarm display is unnecessary. After the control unit 5 performs the process in step S4, the process returns to step S1.

In step S3, the control unit 5 applies a voltage of a predetermined magnitude to the light emitting element 21 of each guided optical sensor 1. This is a process for emitting the light ray Ra from the light emitting element 21 and hitting the object in order to specify the distance between the guided optical sensor 1 and the object. After the control unit 5 performs the process in step S3, the process proceeds to step S5.

In step S5, the control unit 5 measures the voltage generated in the light receiving element 22 that received the light ray Ra emitted from the guided optical sensor 1 in step S3 and reflected by hitting the object, and measures the voltage generated in the light receiving element 22 that receives the light ray Ra that was emitted from the guided optical sensor 1 in step S3 and reflected. Specify the distance (reference distance Db). After the control unit 5 performs the process in step S5, the process proceeds to step S6.

In step S6, the control unit 5 stores the reference distance Db in the storage unit 55. After performing the process in step S5, the control unit 5 proceeds to step S7.

In step S7, the control unit 5 determines whether a certain period of time has elapsed. If a certain period of time has elapsed, if there is a change in the relative position between the guided optical sensor 1 and the object, the distance will change, so the control unit 5 determines whether or not the two are approaching each other. , proceed to step S8 below. If the certain period of time has not elapsed, the control unit 5 repeatedly performs step S7.

In step S8, the control unit 5 applies a voltage of a predetermined magnitude to the light emitting element 21 of each guided optical sensor 1, similarly to step S3. After performing the process in step S8, the control unit 5 proceeds to step S9.

In step S9, the control unit 5 specifies the distance (comparison distance Dc) between the guided optical sensor 1 and the object in the same manner as in step S5. After performing the process of step S9, the control unit 5 proceeds to step S10.

In step S10, the control unit 5 stores the comparison distance Dc in the storage unit 55. After the control unit 5 performs the process in step S10, the process proceeds to step S11.

In step S11, the control unit 5 determines whether the comparison distance Dc is less than or equal to a certain value. If the comparison distance Dc is less than or equal to a certain value, it is considered that there is a high risk of collision between the user and the object, so the control unit 5 proceeds to step S12 below to determine whether or not to display a warning. If the comparison distance Dc exceeds a certain value, the control unit 5 determines that the risk of collision between the user and the object is low, and proceeds to step S4.

In step S12, the control unit 5 determines whether the difference between the comparison distance Dc and the reference distance Db is a negative value. If the difference between the comparison distance Dc and the reference distance Db is negative, the user and the object are close, so the control unit 5 determines that an alarm display is necessary and proceeds to step S13 below. . If the difference between the comparison distance Dc and the reference distance Db is not negative, the user and the object are not close, and the control unit 5 determines that the alarm display is unnecessary and proceeds to step S4.

In step S13, the control section 5 displays a warning on the display section 51. After performing the process of step S13, the control unit 5 returns to step S1.

7 and 8 are diagrams showing the screen of the display unit 51 when the collision prevention system 7 is in operation. In FIG. 7, the display section 51 is displaying information, and since a user (not shown) is walking in the traveling direction D, the acceleration sensor 6 disposed on the back surface of the display section 51 is detecting the walking. Therefore, the light ray Ra is emitted and received from the sensor unit 4 arranged on the back surface of the display section 51, and the distance between the guided optical sensor 1 and the object M is specified by the control section 5. .

In FIG. 8, the object M is moving in the opposite direction to the direction of movement D of the user, and the guided optical sensor 1 and the object M are approaching each other, so an alarm is displayed in the alarm display area 51A of the display unit 51. ing.

The collision prevention system 7 of this embodiment, which is configured and operated as described above, uses the guided optical sensor 1 as a sensor, so it can prevent collisions from the front, including those other than the mobile information terminal user. Danger can be detected, and even if the sensor installation surface is facing vertically downward, it is possible to detect the risk of a collision from the front. As the operating conditions are that the display unit 51 is displaying and that the acceleration detected by the acceleration sensor 6 exceeds a specified value, the user is protected from collisions from the front only when using the smartphone while walking. It is possible to present the danger of In addition, by comparing the reference distance Db and the comparison distance Dc to determine the risk of collision, even if the distance to the object is short, there is no change in the relative position. Alternatively, it is possible to only consider the risk of collision when objects are close together.

Although each embodiment of the present invention has been described above, the technical scope of the present invention is not limited to the above embodiments, and the combination of components may be changed or each component may be modified without departing from the spirit of the present invention. It is possible to make various changes to or delete them.

For example, instead of the array of prisms 31, the light guide section 3 of the guided optical sensor 1 may have a structure in which optical fibers, mirrors, or beads are used to reflect the light rays Ra.

As shown in FIG. 9, a guided optical sensor 1A using an optical fiber includes a core 11 and a cladding 12 in a light guide section 3A. The refractive index of the core 11 is greater than the refractive index of the cladding 12. As shown in FIGS. 10 and 11, the light ray Ra is emitted or received inside the core 11 having a large refractive index, is totally reflected at the interface with the cladding 12, and travels inside the core 11, thereby forming the light emitting element 21. It goes in and out of the light receiving element 22.

The structure of the optical sensor with guide 1 may be symmetrical in the front-rear direction or the left-right direction, so that the user can detect the risk of collision even if the direction of travel is toward the rear or left and right of the optical sensor with guide.

The light guide portion 3 of the optical sensor 1 with a guide is not provided with the diffuser plate 32S, and when the light beam Ra is emitted from the light guide portion 3, the portion of the delivery surface IF of the delivery prism 31F that is hit by the light beam Ra is roughened to reduce the light beam Ra. It may be diffused.

The light guide section 3 of the guided optical sensor 1 may be a light condensing section consisting of a plurality of lenses instead of the condensing section 33 consisting of one lens. As shown in FIG. 12, the guided optical sensor 1B equipped with a light condensing section 33B including a plurality of lenses refracts light rays Ra having the same incident angle to the same angle in the light condensing section 33B, thereby refracting more light rays. The light ray Ra can be received by the light receiving element 22, and the light ray Ra can be easily detected.

In the light guide section 3 of the guided optical sensor 1, a wavelength selection filter may be provided in the condensing section 33. As shown in FIG. 13, the guided optical sensor 1C equipped with the light condensing section 33C provided with the wavelength selection filter 33F does not receive the noise light ray Ra' having a different wavelength from the light ray Ra emitted by the light emitting element 21, but collides with the noise light ray Ra'. Error detection can be prevented.

1, 1A, 1B, 1C Optical sensor with guide 11 Core 12 Clad 2 Optical sensor 21 Light emitting element 22 Light receiving element 3, 3A, 3B, 3C Light guide section 31 Prism 32 Diffusion plate with half mirror 32R Reflection film 32S Diffusion plate 33, 33B, 33C Concentrating section 33F Wavelength selection filter 4 Sensor unit 5 Control section 6 Acceleration sensor 7 Collision prevention system Ra Light beam

Claims (6)

a light-emitting element that emits light when a voltage is applied;
a light guide section that changes the traveling direction of the light beam emitted from the light emitting element;
a light-receiving element that generates a voltage by receiving the light beam emitted from the light guide portion and reflected by hitting an object;
Equipped with
The light guide section includes a diffusion plate with a half mirror that diffuses the light beams emitted from the light guide section and does not transmit the light beams that are reflected by hitting an object , and a diffusion plate that diffuses the light beams that are emitted from the light guide section and is reflected by hitting the object. A light sensor with a guide , comprising: a condensing section for changing the traveling direction of a light beam and guiding the light beam to the light receiving element . The light guide section includes a prism.
The guided optical sensor according to claim 1. The light guide section includes an optical fiber.
The guided optical sensor according to claim 1. the light condensing section is a Fresnel lens;
A guided optical sensor according to any one of claims 1 to 3. A plurality of the guided optical sensors according to any one of claims 1 to 4 ,
a partition section that separates a range in which the light beam is emitted for each of the plurality of guided optical sensors;
a control unit;
Equipped with an acceleration sensor,
The control unit includes:
A display section;
a determination unit that determines whether the display unit is displaying;
Upon receiving the value of acceleration detected by the acceleration sensor and receiving a determination result from the determination unit, application of voltage to the light emitting element is permitted only when the display unit is displaying and the acceleration is greater than a specified value. a permission department to
a voltage processing unit that applies a voltage to the light emitting element at regular time intervals, detects the voltage emitted by the light receiving element, and determines the distance to the object;
a storage unit that stores the distance to the object specified by the voltage processing unit;
The result of comparing the distance to the object stored in the storage unit with the distance to the object after the certain time interval, and whether the distance to the object after the certain time interval is less than a certain value. a calculation unit that determines whether or not the object has approached;
an alarm unit that displays an alarm on the display unit when a determination that the object approaches is received from the calculation unit;
Collision prevention system. comprising the collision prevention system according to claim 5 ;
Mobile information terminal.

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