Electromagnetic wave irradiation device

Abstract

This electromagnetic wave irradiation device comprises: a first irradiation unit that irradiates a first electromagnetic wave; a change unit that changes the traveling direction of the first electromagnetic wave; a first optical member including a first surface on which the first electromagnetic wave from the change unit is incident; a second optical member; and a first detection unit. The second optical member faces the first surface. The second optical member reflects the first electromagnetic wave that has been incident on the first surface and causes the first electromagnetic wave to travel to the first surface. The first detection unit detects the first electromagnetic wave reflected by the second optical member and output from the first surface.

Description

Electromagnetic Wave Irradiation Device Cross-reference to Related Applications

[0001] This application claims the priority of Japanese Patent Application No. 2024-207798, filed in Japan on November 28, 2024, and incorporates the entire disclosure of the previous application herein for reference.

[0002] This disclosure relates to an electromagnetic wave irradiation device.

[0003] In recent years, devices for acquiring information about surrounding objects and the like from the results of detecting electromagnetic waves have been developed. For example, Patent Document 1 discloses a LIDAR (LIght Detection And Ranging) system including a collimator lens that converts laser light into parallel light and a prism that emits the laser light incident on a first surface from a second surface.

[0004] Japanese Patent Application Laid-Open No. 2022-059924

[0005] An electromagnetic wave irradiation device according to an embodiment of this disclosure includes: a first irradiation unit that irradiates a first electromagnetic wave; a changing unit that changes the traveling direction of the first electromagnetic wave; a first optical member including a first surface on which the first electromagnetic wave from the changing unit is incident; a second optical member that faces the first surface and reflects the first electromagnetic wave incident on the first surface to make it travel on the first surface; and a first detection unit that detects the first electromagnetic wave reflected by the second optical member and emitted from the first surface.

[0006] It is a side view of an example of an electromagnetic wave irradiation device according to an embodiment of this disclosure. It is a perspective view of the electromagnetic wave irradiation device shown in FIG. 1. It is a front view of the electromagnetic wave irradiation device shown in FIG. 1. It is a side view of an electromagnetic wave irradiation device according to a comparative example. It is a front view of an electromagnetic wave irradiation device according to a comparative example. It is a side view of an example of an electromagnetic wave irradiation device according to another embodiment of this disclosure.

[0007] If an electromagnetic wave irradiation device that irradiates electromagnetic waves can be miniaturized, it is useful. According to an embodiment of this disclosure, an electromagnetic wave irradiation device can be miniaturized. Hereinafter, embodiments according to this disclosure will be described with reference to the drawings.

[0008] Figure 1 is a side view of an example of an electromagnetic wave irradiation device 1 according to one embodiment of the present disclosure. Figure 2 is a perspective view of the electromagnetic wave irradiation device 1 shown in Figure 1. Figure 3 is a front view of the electromagnetic wave irradiation device 1 shown in Figure 1.

[0009] As shown in Figure 1, the electromagnetic wave irradiation device 1 comprises a first irradiation unit 10, an optical system 11, a second irradiation unit 12, an optical system 13, a demultiplexer 14, a modifier 15, a demultiplexer 16 (third optical member), an optical member 17 (first optical member), and an optical member 18 (second optical member). As shown in Figure 2, the electromagnetic wave irradiation device 1 comprises a plurality of first detection units 19, an optical system 20, an optical system 21, an optical system 22, and a second detection unit 23. As shown in Figure 1, the electromagnetic wave irradiation device 1 comprises a control device 30. For the sake of explanation, the control device 30 is shown only in Figure 1. In Figure 1, the control lines from the control device 30 to the components are shown by dashed lines.

[0010] Figures 1 and 3 show the path 2 of the first electromagnetic wave L1. The first electromagnetic wave L1 is a monitoring electromagnetic wave used to detect the state of the modification unit 15.

[0011] Figure 2 shows the path 3 of the second electromagnetic wave L2. The second electromagnetic wave L2 is an electromagnetic wave used to scan an object outside the electromagnetic wave irradiation device 1. In other words, the second electromagnetic wave L2 is irradiated outside the electromagnetic wave irradiation device 1. The second electromagnetic wave L2 irradiated outside the electromagnetic wave irradiation device 1 is reflected by the object. The reflected wave of the second electromagnetic wave L2 that has been reflected by the object returns to the electromagnetic wave irradiation device 1. Hereafter, the reflected wave of the second electromagnetic wave L2 that has been reflected by the object will simply be referred to as "reflected wave L3 of the second electromagnetic wave". The electromagnetic wave irradiation device 1 measures the distance from the electromagnetic wave irradiation device 1 to the object by detecting the reflected wave L3 of the second electromagnetic wave. Figure 2 shows the path 4 of the reflected wave L3 of the second electromagnetic wave.

[0012] The first irradiation unit 10 irradiates with a first electromagnetic wave L1. As described above, the first electromagnetic wave L1 is a monitoring electromagnetic wave for detecting the state of the modification unit 15. In this embodiment, the deflection angle of the modification unit 15 is detected as the state of the modification unit 15. Therefore, in this embodiment, the first electromagnetic wave L1 is a monitoring electromagnetic wave for detecting the deflection angle of the modification unit 15. The first electromagnetic wave L1 is, for example, visible light. However, the first electromagnetic wave L1 is not limited to visible light. As other examples, the first electromagnetic wave L1 may be infrared rays, ultraviolet rays, or radio waves. The first irradiation unit 10 is configured to include, for example, at least one of a laser diode (LD), a diode laser, and a light-emitting diode (LED).

[0013] The first irradiation unit 10 is fixed and positioned such that the first electromagnetic wave L1 irradiated by the first irradiation unit 10 is incident on the modification unit 15 via the optical system 11 and the demultiplexing unit 14.

[0014] The optical system 11 is incident on the first electromagnetic wave L1 from the first irradiation unit 10. The optical system 11 converts the first electromagnetic wave L1 incident on the first irradiation unit 10 into parallel light. The optical system 11 is configured to include, for example, at least one of a lens and a mirror. The optical system 11 is fixed and positioned at least one of the following: the first electromagnetic wave L1 from the first irradiation unit 10 is incident on it and the incident first electromagnetic wave L1 is emitted to the demultiplexer 14.

[0015] The second irradiation unit 12 irradiates with a second electromagnetic wave L2. The second electromagnetic wave L2 is, for example, infrared light. However, the second electromagnetic wave L2 may be ultraviolet light, visible light, or radio waves. The second irradiation unit 12 is configured to include, for example, at least one of a laser diode, a diode laser, and a light-emitting diode.

[0016] The second irradiation unit 12 is fixed and positioned such that the second electromagnetic wave L2 irradiated by the second irradiation unit 12 is incident on the optical system 20 via the optical system 13.

[0017] The optical system 13 receives the second electromagnetic wave L2 from the first irradiation unit 12. The optical system 13 converts the second electromagnetic wave L2 incident from the second irradiation unit 12 into parallel light. The optical system 13 is configured to include, for example, at least one of a lens and a mirror. The optical system 13 is fixed and positioned at least one of the following: the second electromagnetic wave L2 from the second irradiation unit 12 is incident on it, and the incident second electromagnetic wave L2 is emitted to the optical system 20.

[0018] As shown by path 2 in Figure 1, the first electromagnetic wave L1 is incident on the demultiplexer 14 from the first irradiation unit 10 via the optical system 11. As shown by path 3 in Figure 2, the second electromagnetic wave L2 is incident on the demultiplexer 14 from the second irradiation unit 12 via the optical system 20. As shown by path 4 in Figure 2, the reflected wave L3 of the second electromagnetic wave is incident on the demultiplexer 14 via the modification unit 15. The demultiplexer 14 separates the first electromagnetic wave L1 from the second electromagnetic wave L2 and the reflected wave L3 of the second electromagnetic wave. In this embodiment, the demultiplexer 14 separates the first electromagnetic wave L1 from the second electromagnetic wave L2 and the reflected wave L3 of the second electromagnetic wave by transmitting the incident first electromagnetic wave L1 as shown in Figure 1 and reflecting the incident second electromagnetic wave L2 and the reflected wave L3 of the second electromagnetic wave as shown in Figure 2. The demultiplexer 14 is configured to include, for example, a hot mirror. This hot mirror transmits, for example, a first electromagnetic wave L1 which is visible light, and reflects a second electromagnetic wave L2 which is infrared radiation, and a reflected wave L3 of the second electromagnetic wave.

[0019] The demultiplexer 14 is fixed and positioned such that the first electromagnetic wave L1 from the optical system 11 passes through it and is emitted to the modifier 15. The demultiplexer 14 is fixed and positioned such that the second electromagnetic wave L2 is incident on it from the optical system 20, reflected by the demultiplexer 14, and the reflected second electromagnetic wave L2 propagates to the modifier 15. The demultiplexer 14 is fixed and positioned such that the reflected wave L3 of the second electromagnetic wave from the modifier 15 is incident on it, reflected by the demultiplexer 14, and the reflected wave L3 of the second electromagnetic wave propagates to the optical system 20.

[0020] The first electromagnetic wave L1 is incident on the modification section 15 from the demultiplexer 14, as shown by path 2 in Figure 1. The second electromagnetic wave L2 is incident on the modification section 15 from the demultiplexer 14, as shown by path 3 in Figure 2. The reflected wave L3 of the second electromagnetic wave is incident on the modification section 15 from the demultiplexer 16, as shown by path 4 in Figure 2.

[0021] The modification unit 15 changes the propagation direction of the incident first electromagnetic wave L1, second electromagnetic wave L2, and reflected wave L3 of the second electromagnetic wave. The modification unit 15 is configured to include a reflective mirror, for example, as shown in Figure 1. The first electromagnetic wave L1, second electromagnetic wave L2, and reflected wave L3 of the second electromagnetic wave are incident on the reflective mirror. The modification unit 15 changes the propagation direction of the first electromagnetic wave L1, second electromagnetic wave L2, and reflected wave L3 of the second electromagnetic wave incident on the reflective mirror by changing the orientation of the reflective surface of the reflective mirror. As an example, the reflective mirror can change the orientation of its reflective surface along a predetermined direction as a deflection angle from angle θ1 to angle θn by oscillating around a predetermined axis as the axis of rotation. In this embodiment, the deflection angle of the modification unit 15 detected by the first electromagnetic wave L1 becomes the deflection angle of the reflective mirror.

[0022] In this embodiment, the reflective mirror of the modified section 15 is a MEMS (Micro Electro Mechanical Systems) mirror. However, the reflective mirror is not limited to a MEMS mirror. As another example, the reflective mirror may be a polygon mirror or a galvanometer mirror, etc.

[0023] As shown in Figures 1 and 2, the modification unit 15 is fixed and positioned such that the first electromagnetic wave L1 and the second electromagnetic wave L2 are incident on it from the demultiplexing unit 14, and the first electromagnetic wave L1 and the second electromagnetic wave L2, after their direction of propagation has been changed, are emitted to the demultiplexing unit 16. Furthermore, as shown in Figure 2, the modification unit 15 is fixed and positioned such that the reflected wave L3 of the second electromagnetic wave is incident on it from the demultiplexing unit 16, and the reflected wave L3 of the second electromagnetic wave, after its direction of propagation has been changed, is emitted to the demultiplexing unit 14.

[0024] The first electromagnetic wave L1 and the second electromagnetic wave L2, whose propagation direction has been changed by the modification unit 15, propagate to the demultiplexing unit 16. Here, because the propagation direction of the first electromagnetic wave L1 is changed by the modification unit 15, the path 2 of the first electromagnetic wave L1 changes after the modification unit 15 according to the deflection angle of the modification unit 15. In this embodiment, as shown in Figure 3, the path 2 of the first electromagnetic wave L1 after the modification unit 15 includes paths 2A and 2B. In this embodiment, when the deflection angle of the modification unit 15 becomes a first angle between angle θ1 and angle θn, the first electromagnetic wave L1 propagates along path 2A. Also, when the deflection angle of the modification unit 15 becomes a second angle between angle θ1 and angle θn, the first electromagnetic wave L1 propagates along path 2B. The first angle and the second angle are different angles.

[0025] The first electromagnetic wave L1 is incident on the demultiplexer 16 from the modification unit 15, as shown by path 2 in Figure 1. The second electromagnetic wave L2 is incident on the demultiplexer 16 from the modification unit 15, as shown by path 3 in Figure 2. The reflected wave L3 of the second electromagnetic wave is incident on the demultiplexer 16 from outside the electromagnetic wave irradiation device 1, as shown by path 4 in Figure 2.

[0026] The wave demultiplexer 16 separates the incident first electromagnetic wave L1 from the incident second electromagnetic wave L2 and the reflected wave L3 of the second electromagnetic wave. The wave demultiplexer 16 separates the incident first electromagnetic wave L1 from the incident second electromagnetic wave L2 and the reflected wave L3 of the second electromagnetic wave by reflecting the incident first electromagnetic wave L1 as shown in Figure 1 and by transmitting the incident second electromagnetic wave L2 and the reflected wave L3 of the second electromagnetic wave as shown in Figure 2. The wave demultiplexer 16 is configured, for example, to include a dichroic mirror.

[0027] The demultiplexer 16 propagates the first electromagnetic wave L1 from the modifier 15 to the optical member 17, as shown by path 2 in Figure 1. The demultiplexer 16 is fixed and positioned in such a way that the first electromagnetic wave L1 is incident on it from the modifier 15, and the first electromagnetic wave L1 reflected by the demultiplexer 16 propagates to the optical member 17.

[0028] The demultiplexer 16 propagates the first electromagnetic wave L1 from the modifier 15 to the optical member 17, and propagates the second electromagnetic wave L2 to the outside of the electromagnetic wave irradiation device 1 as shown by path 3 in Figure 2. The demultiplexer 16 is fixed and positioned in such a way that the second electromagnetic wave L2 is incident on it from the modifier 15, passes through the demultiplexer 16, and is emitted to the outside of the electromagnetic wave irradiation device 1.

[0029] The wave splitter 16 propagates the reflected wave L3 of the second electromagnetic wave to the modification unit 15, as shown by path 4 in Figure 2. The wave splitter 16 is fixed and positioned in such a way that the reflected wave L3 of the second electromagnetic wave from outside the electromagnetic wave irradiation device 1 is incident on it, passes through the wave splitter 16, and the transmitted reflected wave L3 propagates to the modification unit 15.

[0030] As shown in Figure 1, the optical member 17 includes a first surface 17a. The first electromagnetic wave L1 from the modification unit 15 is incident on the first surface 17a via the demultiplexing unit 16. In this embodiment, the optical member 17 is a cylindrical lens. This cylindrical lens is plano-convex. The first surface 17a is the cylindrical surface of the cylindrical lens. The convex portion of the cylindrical surface of the first surface 17a faces the demultiplexing unit 16.

[0031] As shown in Figure 1, the optical member 17 includes a second surface 17b opposite to the first surface 17a. The second surface 17b is a plane. The first electromagnetic wave L1 incident from the first surface 17a propagates toward the second surface 17b.

[0032] The optical member 17 is a cylindrical lens and, as shown in Figure 2, has a power direction D1 with power (refractive force) and a no-power direction D2 without power (refractive force). The optical member 17 is fixed and positioned such that the power direction D1 of the optical member 17 is aligned with the direction in which the first electromagnetic wave L1 from the demultiplexer 16 spreads out in a beam shape. The optical member 17 is also fixed and positioned such that the first electromagnetic wave L1 from the demultiplexer 16 is incident on the first surface 17a, and the first electromagnetic wave L1 incident on the first surface 17a is reflected by the optical member 18 and emitted to the first detection unit 19.

[0033] As shown in Figure 1, the optical member 18 faces the first surface 17a of the optical member 17. The optical member 18 reflects the first electromagnetic wave L1 incident on the first surface 17a and causes it to propagate back to the first surface 17a. The optical member 18 is positioned parallel to the second surface 17b. In this embodiment, the optical member 18 is a reflective surface formed on the second surface 17b. Because the optical member 18 is a reflective surface formed on the second surface 17b, the optical member 18 is positioned parallel to the second surface 17b. The reflective surface of the optical member 18 is, for example, a planar mirror. When the optical member 18 is a planar mirror, the angle of incidence of the first electromagnetic wave L1 incident on the optical member 18 and the angle of reflection of the first electromagnetic wave L1 reflected by the optical member 18 are the same.

[0034] As shown in Figure 2, the multiple first detection units 19 include first detection units 19A and 19B. The first detection units 19A and 19B are aligned along the no-power direction D2 of the optical member 17, which is a cylindrical lens. As shown in Figure 3, the first detection units 19 are not located on the path 2 of the first electromagnetic wave L1 from the modification unit 15 to the first surface 17a of the optical member 17. The first detection units 19 are located on the path 2 of the first electromagnetic wave L1 after it has been reflected by the optical member 18 and emitted from the first surface 17a. In Figure 3, the first detection unit 19A is located on the path 2A of the first electromagnetic wave L1 after it has been emitted from the first surface 17a. The first detection unit 19B is located on the path 2B of the first electromagnetic wave L1 after it has been emitted from the first surface 17a.

[0035] As shown in Figure 1, the first detection unit 19 detects the first electromagnetic wave L1 that is reflected by the optical member 18 and emitted from the first surface 17a of the optical member 17. The first detection unit 19 is configured to include, for example, a photodiode (PD). In this embodiment, the first detection unit 19A detects the first electromagnetic wave L1 propagating along path 2A. The first detection unit 19B detects the first electromagnetic wave L1 propagating along path 2B.

[0036] The first detection unit 19 is fixed and positioned such that the first electromagnetic wave L1, which is reflected by the optical member 18 and emitted from the first surface 17a of the optical member 17, is incident on it. In Figure 3, the first detection unit 19A is fixed and positioned such that the first electromagnetic wave L1 propagating along path 2A, from among the first electromagnetic waves L1 whose direction of propagation has been changed by the modification unit 15, is incident on it. The first detection unit 19B is fixed and positioned such that the first electromagnetic wave L1 propagating along path 2B, from among the first electromagnetic waves L1 whose direction of propagation has been changed by the modification unit 15, is incident on it.

[0037] The second electromagnetic wave L2 is incident on the optical system 20 from the optical system 13, as shown by path 3 in Figure 2. The optical system 20 includes a reflective surface that reflects the second electromagnetic wave L2 at the position where the second electromagnetic wave L2 is incident from the optical system 13. The reflective surface is, for example, a mirror. For example, when the second electromagnetic wave L2 from the optical system 13 is incident on the center 20a of the optical system 20, the optical system 20 includes a reflective surface in its center 20a. The optical system 20 reflects the second electromagnetic wave L2 from the optical system 13 using this reflective surface. The second electromagnetic wave L2 reflected by the optical system 20 propagates towards the demultiplexer 14.

[0038] The optical system 20 is fixed and positioned such that the second electromagnetic wave L2 is incident on it from the optical system 13, and the second electromagnetic wave L2 reflected by the optical system 20 propagates to the demultiplexer 14.

[0039] The reflected wave L3 of the second electromagnetic wave is incident on the optical system 20 from the demultiplexer 14, as shown by path 4 in Figure 2. The optical system 20 includes a transparent surface at the position where the reflected wave L3 of the second electromagnetic wave is incident from the demultiplexer 14. For example, if the optical system 20 includes the aforementioned reflective surface in the center 20a of the optical system 20, the optical system 20 includes a transparent surface at a position other than the center 20a. The transparent surface may be an anti-reflective coating. By including a transparent surface at the position where the reflected wave L3 of the second electromagnetic wave from the demultiplexer 14 is incident on the optical system 20, the optical system 20 transmits the reflected wave L3 of the second electromagnetic wave from the demultiplexer 14. The reflected wave L3 of the second electromagnetic wave that has passed through the optical system 20 propagates to the optical system 21.

[0040] The optical system 20 is fixed and / or positioned such that the reflected wave L3 of the second electromagnetic wave is incident from the wavelength division unit 14 and the reflected wave L3 that has passed through the optical system 20 is output to the optical system 21.

[0041] The reflected wave L3 of the second electromagnetic wave is incident on the optical system 21 from the optical system 20. The optical system 21 is configured to include at least one of, for example, a lens and a mirror. The optical system 21 is fixed and / or positioned such that the reflected wave L3 of the second electromagnetic wave is incident from the optical system 20 and the incident reflected wave L3 of the second electromagnetic wave is output to the optical system 22. The reflected wave L3 of the second electromagnetic wave is incident on the optical system 22 from the optical system 21. The optical system 22 is configured to include at least one of, for example, a lens and a mirror. The optical system 22 is fixed and / or positioned such that the reflected wave L3 of the second electromagnetic wave is incident from the optical system 21 and the incident reflected wave L3 of the second electromagnetic wave is output to the second detection unit 23.

[0042] The optical systems 21 and 22 focus the reflected wave L3 of the second electromagnetic wave. The reflected wave L3 of the second electromagnetic wave focused by the optical systems 21 and 22 is incident on the second detection unit 23.

[0043] The reflected wave L3 of the second electromagnetic wave is incident on the second detection unit 23 from the optical system 22. The second detection unit 23 detects the reflected wave L3 of the second electromagnetic wave. The second detection unit 23 is configured to include at least one of, for example, an APD (Avalanche PhotoDiode), a photodiode (PD), and a distance measurement image sensor. The second detection unit 23 is fixed and / or positioned such that the reflected wave L3 of the second electromagnetic wave from the optical system 22 is incident.

[0044] The control device 30 includes a storage unit 31 and a control unit 32.

[0045] The storage unit 31 is configured to include at least one semiconductor memory, at least one magnetic memory, at least one optical memory, or at least two combinations thereof. The storage unit 31 may function as a main memory, an auxiliary memory, or a cache memory. The storage unit 31 stores data used for the operation of the electromagnetic wave irradiation device 1 and data obtained by the operation of the electromagnetic wave irradiation device 1. The storage unit 31 may store a program executed by the control unit 32. The storage unit 31 may store the angle detection table described later.

[0046] The control unit 32 is configured to include at least one processor, at least one dedicated circuit, or a combination thereof. The processor is, for example, a general-purpose processor such as a CPU (Central Processing Unit) or a GPU (Graphics Processing Unit), or a dedicated processor specialized for a specific process. The dedicated circuit is, for example, an FPGA (Field-Programmable Gate Array) or an ASIC (Application Specific Integrated Circuit). The control unit 32 controls each part of the electromagnetic wave irradiation device 1 and executes processes related to the operation of the electromagnetic wave irradiation device 1.

[0047] The control unit 32 detects the state of the changing unit 15 based on the detection result of the first electromagnetic wave L1 by the first detection unit 19. In the present embodiment, the control unit 32 detects the deflection angle of the changing unit 15 as the state of the changing unit 15 based on the detection results of the first detection units 19A and 19B. Here, as described above, when the deflection angle of the changing unit 15 becomes the first angle between the angle θ1 and the angle θn, the first electromagnetic wave L1 propagates along the path 2A. When the deflection angle of the changing unit 15 becomes the second angle between the angle θ1 and the angle θn, the first electromagnetic wave L1 propagates along the path 2B. Therefore, the control unit 32 can detect the timings at which the deflection angle of the changing unit 15 becomes the first angle and the second angle based on the timings at which the first detection units 19A and 19B respectively detect the first electromagnetic wave L1. The control unit 32 may detect the deflection angle of the changing unit 15 at an arbitrary timing based on the angle detection table stored in the storage unit 31. The angle detection table associates the timing at which the deflection angle of the changing unit 15 becomes the first angle or the second angle, the elapsed time from that timing, and the deflection angle of the changing unit 15 at that elapsed time. The angle detection table may associate the timings at which the deflection angle of the changing unit 15 becomes the first angle and the second angle respectively, the elapsed times from those respective timings, and the deflection angles of the changing unit 15 at those respective elapsed times. With such an angle detection table, the control unit 32 can detect the deflection angle of the changing unit 15 at an arbitrary timing.

[0048] The control unit 32 detects the irradiation direction of the second electromagnetic wave L2 irradiated to the outside of the electromagnetic wave irradiation device 1 by detecting the deflection angle of the changing unit 15. The changing unit 15 changes the traveling direction of the incident first electromagnetic wave L1 and also changes the traveling direction of the second electromagnetic wave L2. Therefore, by detecting the deflection angle of the changing unit 15, the irradiation direction of the second electromagnetic wave L2 irradiated to the outside of the electromagnetic wave irradiation device 1 can be detected.

[0049] The control unit 32 detects the distance from the electromagnetic wave irradiation device 1 to the object based on the detection result of the reflected wave L3 of the second electromagnetic wave by the second detection unit 23 and the detected irradiation direction of the second electromagnetic wave L2.

[0050] Here, the electromagnetic wave irradiation device 1X according to the comparative example will be described with reference to Figures 4 and 5. Figure 4 shows a side view of the electromagnetic wave irradiation device 1X according to the comparative example. Figure 5 shows a front view of the electromagnetic wave irradiation device 1X according to the comparative example. Figures 4 and 5 show the path 2X of the first electromagnetic wave L1. As shown in Figure 5, the path 2X of the first electromagnetic wave L1 includes paths 2AX and 2BX.

[0051] Unlike the electromagnetic wave irradiation device 1, the electromagnetic wave irradiation device 1X does not include an optical member 18. Instead of an optical member 18, the electromagnetic wave irradiation device 1X includes a reflective mirror 18X. The reflective mirror 18X reflects the first electromagnetic wave L1 emitted from the second surface 17b of the optical member 17. Unlike the optical member 18, the reflective mirror 18X is not positioned directly opposite the first surface 17a of the optical member 17, but is positioned at an angle to the first surface 17a. The reflective mirror 18X is fixed and positioned in such a way that the reflected first electromagnetic wave L1 travels to the first detection unit 19.

[0052] Thus, the electromagnetic wave irradiation device 1X according to the comparative example is equipped with a reflective mirror 18X instead of the optical member 18. Therefore, the height of the electromagnetic wave irradiation device 1X is higher than the height of the electromagnetic wave irradiation device 1 according to this embodiment by the amount indicated by arrow A in Figures 4 and 5.

[0053] In contrast, the electromagnetic wave irradiation device 1 according to this embodiment includes an optical member 18 facing the first surface 17a of the optical member 17, as shown in Figure 1. Furthermore, the optical member 18 reflects the first electromagnetic wave L1 incident on the first surface 17a and propagates it to the first surface 17a. With this configuration, the height of the electromagnetic wave irradiation device 1 is lower than the height of the electromagnetic wave irradiation device 1X according to the comparative example by the amount indicated by arrow A in Figures 4 and 5. Therefore, according to this embodiment, the electromagnetic wave irradiation device 1 can be miniaturized.

[0054] Furthermore, in the electromagnetic wave irradiation device 1 according to this embodiment, as shown by path 2 in Figure 1, the first electromagnetic wave L1 is incident on the first surface 17a of the optical member 17, then reflected by the optical member 18 and emitted from the first surface 17a. With this configuration, in this embodiment, the first electromagnetic wave L1 passes through the first surface 17a, which is the cylindrical surface of the cylindrical lens, twice. In contrast, in the electromagnetic wave irradiation device 1X according to the comparative example, as shown by path 2X in Figure 1, the first electromagnetic wave L1 passes through the first surface 17a, which is the cylindrical surface of the cylindrical lens, once. Now, let's consider focusing the first electromagnetic wave L1 at the same position in both this embodiment and the comparative example. In this case, in this embodiment, because the first electromagnetic wave L1 passes through the first surface 17a, which is the cylindrical surface of the cylindrical lens, twice, the curvature of the first surface 17a can be made smaller than in the comparative example. In other words, in this embodiment, the radius of curvature of the first surface 17a can be made larger. With this configuration, the thickness of the optical element 17 can be reduced in this embodiment. As a result, the electromagnetic wave irradiation device 1 can be further miniaturized.

[0055] <Other Embodiments> In the electromagnetic wave irradiation device 1 shown in Figure 1, the optical member 18 (second optical member) was described as a reflective surface formed on the second surface 17b of the optical member 17 (first optical member). However, in the electromagnetic wave irradiation device of this disclosure, the second optical member is not limited to a reflective surface formed on the second surface of the first optical member. The electromagnetic wave irradiation device of this disclosure may include a second optical member that faces the first surface and reflects the first electromagnetic wave L1 incident on the first surface, causing it to propagate to the first surface. Hereinafter, an electromagnetic wave irradiation device 101 according to another embodiment of this disclosure will be described.

[0056] Figure 6 is a side view of an example of an electromagnetic wave irradiation device 101 according to another embodiment of the present disclosure. Like the electromagnetic wave irradiation device 1, the electromagnetic wave irradiation device 101 comprises a first irradiation unit 10, an optical system 11, a second irradiation unit 12, an optical system 13, a demultiplexing unit 14, a modification unit 15, a demultiplexing unit 16 (third optical member), and an optical member 17 (first optical member). Like the electromagnetic wave irradiation device 1, the electromagnetic wave irradiation device 101 comprises a plurality of first detection units 19, an optical system 20, an optical system 21, an optical system 22, a second detection unit 23, and a control device 30. However, unlike the electromagnetic wave irradiation device 1, the electromagnetic wave irradiation device 101 comprises an optical member 118 (second optical member).

[0057] The optical member 118 reflects the first electromagnetic wave L1 emitted from the second surface 17b of the optical member 17. The optical member 118 is, for example, a reflective mirror. The optical member 118 is positioned parallel to the second surface 17b of the optical member 17. The optical member 118 is positioned away from the second surface 17b of the optical member 17. However, the optical member 118 may be positioned in close contact with the second surface 17b of the optical member 17. The optical member 118 is positioned on the opposite side of the first surface 17a of the optical member 17 from the second surface 17b of the optical member 17. The optical member 118 is fixed and positioned such that the first electromagnetic wave L1 is incident on the optical member 17 from the second surface 17b, reflected by the optical member 118, and then emitted from the first surface 17a of the optical member 17 and incident on the first detection unit 19. The reflective mirror of the optical element 118 is, for example, a planar mirror. When the optical element 118 is a planar mirror, the angle of incidence of the first electromagnetic wave L1 incident on the optical element 118 and the angle of reflection of the first electromagnetic wave L1 reflected by the optical element 118 are the same.

[0058] Other configurations of the electromagnetic wave irradiation device 101 according to other embodiments are the same as or similar to those of the electromagnetic wave irradiation device 1 shown in Figure 1. Such electromagnetic wave irradiation devices 101 according to other embodiments can achieve the same or similar effects as the electromagnetic wave irradiation device 1 shown in Figure 1.

[0059] While embodiments relating to this disclosure have been described based on the drawings and examples, it should be noted that those skilled in the art can make various modifications or alterations based on this disclosure. Therefore, it should be noted that these modifications or alterations are included within the scope of this disclosure. For example, the functions included in each component can be rearranged in a logically consistent manner, and multiple components can be combined into one or separated. These are also to be understood as being included within the scope of this disclosure.

[0060] For example, in the embodiment described above, the electromagnetic wave irradiation device 1,101 was described as comprising two first detection units 19, namely first detection units 19A and 19B. However, the electromagnetic wave irradiation device 1,101 may comprise one first detection unit 19, or three or more first detection units 19.

[0061] For example, an embodiment is also possible in which a general-purpose computer functions as the electromagnetic wave irradiation device 1 or electromagnetic wave detection device 101 according to the above-described embodiment. Specifically, a program describing the processing content that realizes each function of the electromagnetic wave irradiation device 1 or electromagnetic wave detection device 101 according to the above-described embodiment is stored in the memory of the general-purpose computer, and the processor reads and executes the program. Therefore, this disclosure can also be realized as a program that can be executed by a processor, or as a non-temporary computer-readable medium that stores the program.

[0062] In one embodiment, (1) the electromagnetic wave irradiation device includes a first irradiation unit that irradiates a first electromagnetic wave; a changing unit that changes the direction of propagation of the first electromagnetic wave; a first optical member including a first surface to which the first electromagnetic wave from the changing unit is incident; a second optical member that faces the first surface and reflects the first electromagnetic wave incident on the first surface, causing it to propagate to the first surface; and a first detection unit that detects the first electromagnetic wave that is reflected by the second optical member and emitted from the first surface.

[0063] (2) In the electromagnetic wave irradiation device described in (1) above, the first optical member is a cylindrical lens, the first surface is the cylindrical surface of the cylindrical lens, the cylindrical lens includes a planar second surface on the opposite side of the first surface, and the second optical member is a reflective surface formed on the second surface.

[0064] (3) In the electromagnetic wave irradiation device described in (1) above, the first optical member is a cylindrical lens, the first surface is the cylindrical surface of the cylindrical lens, the cylindrical lens includes a second planar surface on the opposite side of the first surface, and the second optical member reflects the first electromagnetic wave emitted from the second surface.

[0065] (4) In the electromagnetic wave irradiation device described in any one of (1) to (3) above, the first detection unit is not located on the path of the first electromagnetic wave from the modification unit to the first surface.

[0066] (5) The electromagnetic wave irradiation device described in any one of (1) to (4) above further comprises a third optical member that propagates the first electromagnetic wave from the modification unit to the first optical member.

[0067] (6) The electromagnetic wave irradiation device described in (5) above further comprises a second irradiation unit that irradiates a second electromagnetic wave, the modification unit changes the direction of propagation of the first electromagnetic wave and the second electromagnetic wave, the first electromagnetic wave and the second electromagnetic wave whose direction of propagation has been changed by the modification unit propagate to the third optical member, and the third optical member causes the first electromagnetic wave to propagate to the first optical member and the second electromagnetic wave to propagate to the outside of the electromagnetic wave irradiation device.

[0068] (7) The electromagnetic wave irradiation device described in (6) above further comprises a second detection unit for detecting the reflected wave of the second electromagnetic wave that has been reflected by an object.

[0069] (8) The electromagnetic wave irradiation device described in any one of (1) to (7) above further comprises a control unit that detects the state of the modification unit based on the detection result of the first electromagnetic wave of the first detection unit.

[0070] In this disclosure, the designations "First," "Second," etc., are identifiers used to distinguish the configurations. Configurations distinguished by the designations "First," "Second," etc., in this disclosure may have their numbers swapped. For example, the first irradiation unit may swap the identifiers "First" and "Second" with the second irradiation unit. The swapping of identifiers occurs simultaneously. The configurations remain distinguishable even after the swapping of identifiers. Identifiers may be deleted. Configurations from which identifiers have been deleted are distinguished by codes. The designations "First," "Second," etc., in this disclosure should not be used alone to interpret the order of the configurations or to justify the existence of smaller numbered identifiers.

[0071] 1, 101: Electromagnetic wave irradiation device, 2A, 2B: Path of the first electromagnetic wave, 3: Path of the second electromagnetic wave, 4: Path of the reflected wave of the second electromagnetic wave, 10: First irradiation unit, 11: Optical system, 12: Second irradiation unit, 13: Optical system, 14: Demultiplexing unit, 15: Modification unit, 16: Demultiplexing unit (third optical element), 17: Optical element (first optical element), 17a: First surface, 17b: Second surface, 18, 118: Optical element (second optical element), 20: Optical system, 21: Optical system, 22: Optical system, 30: Control device, 31: Memory unit, 32: Control unit, L1: First electromagnetic wave, L2: Second electromagnetic wave, L3: Reflected wave of the second electromagnetic wave

Claims

1. An electromagnetic wave irradiation device comprising: a first irradiation unit that irradiates a first electromagnetic wave; a changing unit that changes the direction of propagation of the first electromagnetic wave; a first optical member including a first surface to which the first electromagnetic wave from the changing unit is incident; a second optical member facing the first surface and reflecting the first electromagnetic wave incident on the first surface to propagate it to the first surface; and a first detection unit that detects the first electromagnetic wave that is reflected by the second optical member and emitted from the first surface.

2. The electromagnetic wave irradiation device according to claim 1, wherein the first optical member is a cylindrical lens, the first surface is the cylindrical surface of the cylindrical lens, the cylindrical lens includes a planar second surface on the opposite side of the first surface, and the second optical member is a reflective surface formed on the second surface.

3. The electromagnetic wave irradiation device according to claim 1, wherein the first optical member is a cylindrical lens, the first surface is the cylindrical surface of the cylindrical lens, the cylindrical lens includes a second planar surface on the opposite side of the first surface, and the second optical member reflects the first electromagnetic wave emitted from the second surface.

4. The electromagnetic wave irradiation device according to any one of claims 1 to 3, wherein the first detection unit is not located on the path of the first electromagnetic wave from the modification unit to the first surface.

5. The electromagnetic wave irradiation device according to any one of claims 1 to 4, further comprising a third optical member for propagating the first electromagnetic wave from the modified portion to the first optical member.

6. The electromagnetic wave irradiation device according to claim 5, further comprising a second irradiation unit for irradiating a second electromagnetic wave, wherein the modification unit changes the propagation direction of the first electromagnetic wave and the second electromagnetic wave, the first electromagnetic wave and the second electromagnetic wave whose propagation direction has been changed by the modification unit propagate to the third optical member, and the third optical member causes the first electromagnetic wave to propagate to the first optical member and the second electromagnetic wave to propagate to the outside of the electromagnetic wave irradiation device.

7. The electromagnetic wave irradiation device according to claim 6, further comprising a second detection unit for detecting the reflected wave of the second electromagnetic wave that has been reflected by an object.

8. The electromagnetic wave irradiation device according to any one of claims 1 to 7, further comprising a control unit that detects the state of the modification unit based on the detection result of the first electromagnetic wave of the first detection unit.

Images