JP5065701B2 - Laser scanning device - Google Patents

Description

  The present invention relates to a laser scanning device that scans a laser beam by moving an optical element in a direction perpendicular to an optical axis.

  2. Description of the Related Art Laser scanning devices that scan laser light and perform distance measurement are used in vehicle-mounted distance measuring devices and the like. For example, Japanese Patent Application Laid-Open No. 10-123252 discloses a laser scanning device in which a lens holder provided with a light projection lens is supported by a plurality of coil springs. By supporting the light projecting lens with a coil spring, the apparatus configuration can be simplified and the cost can be reduced.

  In Japanese Patent Laid-Open No. 10-123252, the lens is simply scanned, but in recent years, in order to improve the accuracy of distance measurement, it is required to control the projection position, that is, the position control of the projection lens. In order to control the position of the projection lens, it is necessary to accurately know the position of the projection lens.

If a position detection element that detects the position of the center of gravity of light is used as this position sensor, highly accurate position detection can be realized. That is, it is possible to detect at the micron order at the lens holder portion and control the light projection position at a 0.1 degree level. In this position detection, for example, the position detection element is fixed to the fixing portion, and a slit that allows light to pass through in a thin line shape is attached to the lens holder. Then, the light emitting diode is fixed to a fixing portion on the opposite side of the position detection element across the slit, and the light moves on the position detection element by the movement of the slit. And position detection is performed as the gravity center position of this light. When the maximum sensitivity wavelength is 960 nm, if there is the same wavelength, a 960 nm light emitting diode is used. If there is no same wavelength, for example, a light emitting diode that emits light at 950 nm is used.
JP-A-10-123252

  By the way, the wavelength of the laser beam to be scanned is around 870 nm. The position detection element has sensitivity in a wide range of 760 to 1100 nm even when the maximum sensitivity wavelength is 960 nm. Therefore, the position detection element also responds to the laser beam to be scanned. When the laser light leaks into the position detection element, the position detection element performs erroneous detection, and the obtained position information becomes incorrect.

  The laser light is intermittently lit for distance measurement. If this leaks into the position detection element, the position signal will oscillate at intermittent intervals. This appears in the position signal as noise, and accurate position detection cannot be performed, and control based on such a position signal causes a problem that the projection lens swings.

  The present invention has been made paying attention to such a problem, and an object of the present invention is to provide a laser scanning apparatus capable of suppressing the influence of the laser beam to be scanned and accurately detecting the position.

In order to achieve the above object, a laser scanning apparatus according to a first aspect of the present invention includes an optical element, a holder that holds the optical element, and the holder in a direction perpendicular to the optical axis of the optical element. Support means for movably supporting, a first light emitting element for emitting laser light to be incident on the optical element, a position detection sensor for detecting the position of the center of gravity for detecting the position of the holder, and the position A laser scanning device for use in an in-vehicle distance measuring device comprising: a second light emitting element that emits light incident on the detection sensor, wherein the light receiving surface of the position detection sensor is: (1) light of the optical element It is perpendicular to the axial direction and faces the exit surface side of the optical element, and is arranged at a position on the exit surface side of the optical element with respect to the entrance surface of the optical element with respect to the optical axis direction of the optical element , or ( 2) The light It is perpendicular to the optical axis direction of the optical element and faces the incident surface side of the optical element, and is disposed at a position on the incident surface side of the optical element with respect to the exit surface of the optical element with respect to the optical axis direction of the optical element. It is characterized by that .

  According to the first aspect of the present invention, it is possible to prevent the reflected light from the incident surface of the scanning laser beam from entering the position detection sensor, thereby enabling accurate position detection. .

According to the invention described in claim 1, further unnecessary light from the optical element exit surface of the scanning laser beam can be prevented from entering the position detecting sensor, an accurate position detection by this be able to.

According to the second aspect of the present invention, it is possible to attenuate the reflected light on the optical element incident surface of the laser beam to be scanned to prevent the laser beam from entering the position detection sensor, thereby performing accurate position detection. be able to.

According to the third aspect of the present invention, the reflected light from the optical element incident surface of the laser beam to be scanned can be sufficiently attenuated to prevent the laser beam from entering the position detection sensor, thereby enabling accurate position detection. It can be carried out.

According to the fourth aspect of the present invention, the reflected light from the optical element incident surface of the laser beam to be scanned can be sufficiently attenuated to prevent the laser beam from entering the position detection sensor, thereby enabling accurate position detection. It can be carried out.

According to the fifth aspect of the present invention, the effects of any of the first to fourth aspects of the invention can be enjoyed better.

According to the sixth aspect of the invention, good optical characteristics can be obtained.

According to the seventh aspect of the invention, good optical characteristics can be obtained.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

(First embodiment)
FIGS. 1 to 15 show a first embodiment of the present invention. FIGS. 1 to 3 are perspective views of the laser scanning apparatus of the present invention, and FIG. 4 is a laser cut along line AA in FIG. 5 is a cross-sectional perspective view of the entire scanning apparatus, FIG. 5 is a cross-sectional view thereof, FIG. 6 is a cross-sectional view of the entire laser scanning apparatus cut along line BB in FIG. 5, FIG. 7 is an exploded perspective view, and FIGS. FIG. 10 is a sectional view of the entire biaxial actuator section taken along the line CC in FIG. 5, and FIGS. 11 and 12 are exploded perspective views of the biaxial actuator section set. FIG. 13 is an exploded perspective view of the spring receiving portion set constituting the biaxial actuator portion set, FIG. 14 is an example of use of the in-vehicle ranging device using the laser scanning device according to the first embodiment, and FIG. It is a figure for demonstrating the structure used as the characteristic of 1st Embodiment. In each figure, the coordinate axes of X, Y, and Z are shown. Here, in each axis, the direction of the arrow is defined as the + direction, and the direction opposite to the arrow is defined as the-direction. For example, in the case of the X axis, the direction of the arrow is the X + direction (X + side), and the direction opposite to the arrow is the X− direction (X− side). Similarly, for the Y axis, the direction of the arrow is the Y + direction (Y + side), and the direction opposite to the arrow is the Y− direction (Y− side). Similarly, for the Z axis, the direction of the arrow is the Z + direction (Z + side), and the direction opposite to the arrow is the Z− direction (Z− side).

  As shown in FIG. 5 and FIG. 10, a scanning lens (hereinafter simply referred to as a lens) 5 is bonded and fixed as an optical element by being applied in the Z direction to a stepped portion 8 of a holder 7 made of polyphenylene sulfide resin containing glass. Yes. In the X + direction of the holder 7, an air-core azimuth coil 15 wound with a copper clad aluminum wire is bonded and fixed so that the center air-core portion is fitted to the convex portion 9 provided on the holder 7. ing. At both ends in the Y direction, air-core elevation coils 16a and 16b wound with copper-clad aluminum wires are fitted into the convex portions 10a and 10b provided on the holder 7 with the center air-core portions thereof, Bonded and fixed.

  The substrate 17 is also bonded and fixed to the holder 7. Although not shown, the ends of the azimuth coil 15 and the elevation coils 16 a and 16 b are soldered to the substrate 17.

  In the Z-direction of the holder 7, a stepped portion 21 of the holder 20 made of a liquid crystal polymer containing carbon fibers is applied to the tip end portion 14 of the holder 7 and is fixedly bonded. Here, the stepped portion 23 of the holder 20 faces the lens 5 and the rib-shaped portion 22 faces the substrate 17 with a very slight gap of about 0.05 mm. By applying an adhesive to the gap, the gap is filled with the adhesive, and the lens 5 and the substrate 17 are not only bonded and fixed to the holder 7 but also fixed between the holder 7 and the holder 20. As a result, it is fixed more firmly. Furthermore, if heat caulking is used together for fixing the holder 7 and the holder 20, the durability can be further improved.

  As shown in FIG. 11, the holder 20 is provided with slits 24a and 24b as optical elements. In the longitudinal direction of the slits 24a and 24b, the slit 24a is in the Y direction and the slit 24b is in the X direction. In order to allow light to pass through the slits 24 a and 24 b, the holder 7 is provided with holes 12 as shown in FIGS. 5 and 13, and the substrate 17 is provided with holes 19.

  The group consisting of the holder 7 and the parts fixed to the holder 7 is referred to as the movable unit 27.

  As shown in FIG. 11, holes 18 a to 18 h (not shown because 18 a and 18 e to 18 h are not visible) are provided in the substrate 17, and beryllium copper wire springs 28 a to 28 h (holder support means) are inserted into one end. Are soldered (solder is not shown). Also in the holder 7, holes 13a to 13h are provided in portions where the wire springs 28a to 28h pass as shown in FIG. Also in the holder 20, holes 25a to 25d are formed on the Z-side of the wire springs 28a to 28h as shown in FIG. Soldering of the wire springs 28a to 28h to the substrate 17 is performed using the holes 25a to 25d after the assembly of the movable portion 27 is completed. Thereby, the bonding work of the holder 7 and the holder 20 can be performed without the wire springs 28a to 28h, the wire springs 28a to 28h can be prevented from being bent or broken, and workability can be improved.

  The wire springs 28 a to 28 h are connected to the azimuth coil 15 and the elevation coils 16 a and 16 b through the substrate 17. Wire springs 28c and 28d are connected to one end of the azimuth coil 15, and wire springs 28g and 28h are connected to the other end. That is, two wire springs are connected in parallel to the azimuth coil 15. The elevation coils 16a and 16b are connected in series on the substrate 17. Similarly, wire springs 28a and 28b are connected to one end, and wire springs 28e and 28f are connected to the other end.

  Next, the spring receiving portion set 29 will be described. As shown in FIGS. 5 and 13, the lens 6 is inserted into the stepped portion 37 of the hole 36 of the spring receiver 30 made of polyphenylene sulfide resin containing glass. A holding spring 45 made of silicone rubber is fitted to the stepped portion 38 on the Z-side of the lens 6, and a holding can 46 made of glass-filled polyphenylene sulfide resin is stepped on the Z-side. Part 39 is fitted.

  A substrate 48 is disposed on the Z + side of the spring receiver 30, and an iron yoke 55 is disposed on the Z− side. The board 48 and the yoke 55 are fixed by screwing screws 54 a and 54 b through the holes 52 a and 52 b of the board 48 and the holes 33 a and 33 b of the spring receiver 30 and screwing them into the screw holes 57 a and 57 b of the yoke 55. That is, the board 48 and the spring receiver 30 are sandwiched between the screw head and the yoke 55 by the two screws 54a and 54b.

  As shown in FIG. 9, the substrate 48 is positioned by the holes 53 a and 53 b of the substrate 48 and the convex portions 40 a and 40 b of the spring receiver 30. The hole 53a is a long hole, and prevents the assembly by dimensional deviation due to tolerance. In the center of the substrate 48, a hole 50 for passing light is provided.

  On the other hand, as shown in FIGS. 10 and 13, the yoke 55 is positioned in the Y direction by aligning the Y-surface 65 of the spring receiver 30 and the Y-end 61 of the yoke 55. The X direction is positioned by the convex portion 34 of the spring receiver 30 and the hole 60 of the yoke 55.

  If there is nothing, the presser can 46 described above is more convex than the spring receiver 30 in the Z-direction due to the elasticity of the presser spring 45. As shown in FIG. 5, this is pressed by the yoke 55, the pressing can 46 is in the same position as the spring receiver 30 in the Z-direction, and the lens 6 is fixed by the elasticity of the pressing spring 45. In addition to the substrate 48 and the yoke 55, the lens 6 is also fixed by the two screws 54a and 54b.

  In the spring receiver 30, a light emitting diode 47 (second light emitting element) is also fitted in the cylindrical hole 32 at the back of the hole 31, and the legs are soldered through the holes 51 a and 51 b of the substrate 48. The light receiving portion of the light emitting diode 47 and the substrate 48 are fixed so as to sandwich the spring receiver 30.

  In the above, the part made up of the spring receiver 30 and the parts fixed to the spring receiver 30 is referred to as the spring receiver part set 29.

  The opposite side of the wire springs 28 a to 28 h soldered to the movable portion 27 is inserted into the holes 41 a to 41 d of the spring receiver 30 through the holes 56 a to 56 d of the yoke 55.

  The inside of the holes 41a to 41d of the spring receiver 30 is represented by a portion D in FIG. The hole 41d becomes a thin hole 43g on the Z + side. Furthermore, the hole 42g has a diameter slightly larger than the wire spring 28g on the Z + side. Two wire springs 28g and 28h are inserted into the hole 41d, but the number of the holes 41d is one. On the other hand, one hole 43g, 43h, 42g, 42h (43h, 42h is not shown) is provided for each wire spring, and the hole 41d is divided into two at the back. The holes 43g and 43h are connected to the conical side surface from the hole 41d.

  The holes 43g and 43h are filled with an ultraviolet curable silicone gel 67. Filling is performed from the hole 56 d of the yoke 55 and the hole 41 d of the spring receiver 30. The filling operation is performed with the Z-side up, and the silicone gel 67 is guided to the holes 43g and 43h through the hole 41d shaped like a conical side surface. The work ends when the hole 41d is shaped like a conical side surface. At this time, the silicone gel flows accurately through the holes 42g and 42h. However, the silicone gel has a high viscosity and is difficult to flow into a narrow gap even before curing. Therefore, the silicone gel can be prevented from flowing into the holes 42g and 42h by quickly working and curing with ultraviolet rays.

  The other wire springs 28a to 28f and the holes 41a to 41c of the spring receiver 30 have the same configuration. The vibration of the wire springs 28a to 28h is damped by the silicone gel.

  The wire springs 28a to 28h protrude from the spring receiver 30 in the Z + direction, and are inserted into the holes 49a to 49h of the substrate 48 and soldered. The board 48 is connected to a control board (not shown). In the azimuth coil 15 and the elevation coils 16a and 16b, the light emitting diode 47 is also connected to the control board via the wire springs 28a to 28h.

  The movable portion 27 is supported by the wire springs 28a to 28h so as to be movable in the X direction and the Y direction. Here, if the movable portion 27 is simply supported so as to be movable in the X direction and the Y direction, four wire springs are sufficient. The reason why the number of wires is eight is that the wires of the azimuth coil 15 and the elevation coils 16a and 16b are arranged in parallel with two wire springs, so that the resistance value of the wire spring portion is reduced.

  Next, as shown in FIG. 12, the iron yoke 68 to which the azimuth magnet 78 and the elevation magnets 79a and 79b are bonded covers the movable portion 27 from the Z-direction as shown in FIG. Fixed to the set 29.

  The yoke 68 is attached to the yoke 55 by the attraction force of the azimuth magnet 78 and the elevation magnets 79a and 79b. At this time, as shown in FIG. 8, the corners 76a and 76b of the yoke 68 and the convex part 63 of the yoke 55 are combined, and as shown in FIG. 9, the corners 74a and 74b of the yoke 68 and the convex parts 62a and 62b of the yoke 55 are combined. Position.

  The Y dimension (distance between Y-end 61 and Y + ends 64a and 64b) of the portion of yoke 55 to which yoke 68 is attached is 0 with respect to the Y dimension (distance between Y-plane 65 and Y + plane 66) of spring receiver 30. It is about 1mm larger. As shown in FIG. 10, the Y-side 65 of the spring receiver 30 on the Y-side, the Y-end 61 of the yoke 55, and the contact portion 75 of the yoke 68 are in the same position as in the Y direction. From the Y + surface 66, the Y + ends 64a and 64b of the yoke 55 and the contact portions 77a and 77b of the yoke 68 are outside. This prevents the contact portions 77a and 77b of the yoke 68 from coming into contact with the Y + surface 66 of the spring receiver 30 and not coming into contact with the Y + ends 64a and 64b of the yoke 55 due to deviation due to tolerances. 68 can be contacted to form an efficient magnetic circuit.

  The yoke 68 is attracted to the yoke 55 only by the attraction force of the azimuth magnet 78 and the elevation magnets 79a and 79b. However, the screws 68a and 84b are used as shown in FIGS. The spring receiver 30 is screwed. The screws 84 a and 84 b are inserted into holes 35 a and 35 b provided in the spring receiver 30, and are fastened to the screw holes 70 a and 70 b of the yoke 68. The holes 35a and 35b are sized so that the heads of the screws 84a and 84b can enter, but the diameter is narrow so that only the screw portion passes through the back.

  As shown in FIGS. 8 and 11, the substrate 68 is fixed to the yoke 68 by screw holes 71a and 71b of the yoke 60, holes 82a and 82b of the substrate 80, and screws 83a and 83b.

  As shown in FIG. 12, position sensors 81a and 81b whose output current changes depending on the position of the center of gravity of light are soldered to the substrate 80. As shown in FIG. 5, the position sensors 81 a and 81 b are formed so as to protrude from the hole 72 of the yoke 68 toward the Z + side. The light receiving surfaces 85a and 85b of the position sensors 81a and 81b are directed in the direction Z + side of the light emitting diode 47, and are on the Z + side in the Z direction from the incident surface 86 of the lens 5.

  Although not shown, the board 80 is connected to a control board (not shown) via an electric wire, and the position sensors 81a and 81b are connected to the control board.

  As is apparent from FIG. 4, the position sensor 81a is disposed at the slit 24a, and the position sensor 81b is disposed at a position facing the slit 24b. Light from the light emitting diode 47 spreads and enters both the slits 24a and 24b. The yoke 55 in the middle is provided with a hole 58 for passing light. Although the slits 24a and 24b are moved by the movement of the movable portion 27, the light from the light emitting diode 47 is sufficiently spread in the moving range, and the light passing through the slits 24a and 24b reaches the position sensors 81a and 81b. When the light passing through the slits 24a and 24b moves due to the movement of the movable portion 27, the center of gravity of the light on the position sensors 81a and 81b moves, and the position of the movable portion 27 is detected.

  In addition, since the light emitting diode 47 emits infrared rays, the light is not actually visible. As the position sensors 81a and 81b, those having sensitivity in the infrared region of 760 to 1100 nm are used.

  Each of the position sensors 81a and 81b is a one-dimensional sensor that detects a position in one direction. The position sensor 81a facing the slit 24a whose Y direction is the longitudinal direction is a slit whose detection direction is the X direction and whose X direction is the longitudinal direction. In the position sensor 81b facing 24b, the detection direction is the Y direction.

  By moving the lens 5 mounted on the movable portion 27, the irradiation position of light from a laser diode (first light emitting element) 1 described later is moved, but the irradiation position is inclined with respect to the optical axis of the lens 5. The position of the substrate 80 is adjusted and fixed in the XY plane so that the output of the position sensors 81a and 81b becomes an output indicating the 0 position when the desired position such as the 0 position is reached. . For this reason, the holes 82a and 82b of the substrate 80 are large in view of the adjustment allowance.

  As shown in FIG. 12, the holder 7 is provided with convex portions 11a to 11d, and the holder 20 is provided with convex portions 26a to 26d as shown in FIG. When the movable portion 27 moves, the former hits the hole 59 of the yoke 55 and the latter hits the hole 73 of the yoke 68, which serves as a stopper that limits the amount of movement. Since the convex portions are at the four corners and the holes are also square, movement in the X direction, the Y direction, and both directions can be restricted. If one side is provided on both sides in the Z direction, the movable part 27 rotates around the Y axis in the X direction movement, and around the X axis in the Y direction movement, and the wire springs 28a to 28h may be bent. It is because there is sex.

  The assembly configured as described above is called a biaxial actuator 87.

  As shown in FIGS. 3 and 7, the biaxial actuator 87 is screwed to a main body 89 made of glass-containing polyphenylene sulfide resin by screws 88a to 88c. The screws 88 a to 88 c are screwed into the screw holes 69 a to 69 c of the yoke 68 of the biaxial actuator 87. Although not shown, the spring receiver 30 is provided with a recess for escaping the ends of the screws 88a to 88c. A hole is formed in the main body 89 corresponding to the screws 88a to 88c.

  The main body 89 is provided with a convex portion 90 in the Y + direction. The position adjustment of the substrate 80 of the biaxial actuator 87 is performed after the biaxial actuator 87 is attached to the main body 89. As shown in FIGS. 2 and 6, since the screw 83 b is not covered with the convex portion 90, it can be normally tightened even after the biaxial actuator 87 is attached to the main body 89. On the other hand, since the screw 83 a is hidden behind the convex portion 90, a hole 91 is provided in the convex portion 90. The screw 83a can be tightened from the hole 91 through the driver.

  The mirror 4 is bonded to a surface 92 that forms an angle of 45 degrees with respect to the XY plane and the YZ plane of the main body 89. A hole 95 is provided in the surface 92, and as shown in FIG. 5, the surface 96 on the hole 95 side of the mirror 4 is a reflecting surface.

  As shown in FIGS. 6 and 7, a lens frame 98 is fixed to the main body 89 by screws 103. The screw 103 is passed through the hole 98 of the main body, and the tip is screwed into the screw hole 102 of the lens frame 98, and the lens frame 98 is fixed to the main body 89 with a so-called pulling screw. The lens 2 is bonded and fixed to the stepped portion 100 of the hole 99 of the lens frame 98, and the lens 3 is bonded and fixed to the stepped portion 101.

  The lens frame 98 is inserted into the hole 93 of the main body 89. The diameter of the hole 93 is slightly larger than the diameter of the lens frame 98. When the lens frame 98 is moved in the X direction along the hole 93 and the lens 2 and the lens 3 are moved, the size of the spot of light emitted from this apparatus changes. Therefore, the lens frame 98 is moved in the X direction so that the spot size is adjusted to a predetermined size. For this adjustment, the hole 98 of the main body 89 is a long hole in the X direction.

  As shown in FIGS. 1 and 7, the laser diode 1 is further fixed in the hole 93 of the main body 89. The laser diode 1 is press-fitted into a brass ita 104. The screws 106 a and 106 b are passed through the holes 105 a and 105 b of the ita 104 and screwed into the screw holes 94 a and 94 b of the main body 89, so that the ita 104 is screwed to the main body 89. At this time, the position of the ita 104 is adjusted in the YZ plane so that the optical axes of the laser diode 1 and the lenses 2 and 3 coincide. Although not shown, the laser diode 1 is connected to a laser driver substrate.

  As shown in FIGS. 4 and 5, the laser light emitted from the laser diode 1 passes through the lenses 2 and 3, the optical path is bent 90 degrees by the mirror 4, reaches the lens 5, and further passes through the lens 6. Has been. At this time, the light emitted from the laser diode 1 first passes through the hole 93 in the convex portion 90 of the main body 89, passes through the hole 99 in the lens frame 98, and then returns to the hole 93. The hole 95 is entered through 107, the direction is changed by the mirror 4, and the hole 95 is advanced. Light will first exit the body 89 at the outlet 108 in the hole 95. The convex portion 90 of the main body 89 has a convex portion 97 in the Z + direction so that the distance from the exit 108 to the incident surface 86 of the lens 5 is reduced. Further, the wall 128 of the convex portion 97 has a rough surface. The wavelength of the laser diode 1 is 870 nm, which is infrared, and the light cannot actually be seen visually.

  Next, the operation of the in-vehicle distance measuring device using the laser scanning device of the present embodiment configured as described above will be described.

  FIG. 14 schematically shows an in-vehicle distance measuring device using the laser scanning device of the present embodiment.

  Laser light emitted from the laser diode 1 is swung left and right as indicated by an arrow 110 by moving the lens 5 of the holder 7 supported by the wire spring 28 left and right as indicated by an arrow 109 via the lenses 2 and 3. In FIG. 14, the mirror 4 is omitted. Further, the light is finally formed into a desired beam shape and irradiated to the range indicated by the arrow 111 by passing through the lens 6. The light 114 reflected when the irradiated light 112 hits the obstacle 113 reaches the photodetector 116 via the light receiving lens 115, and the distance to the obstacle 123 is calculated by an electric circuit. Actually, the lens 5 is swung not only right and left but also vertically, and light is swung up and down.

  The mechanism for moving the lens 5 up, down, left and right will be described in more detail.

  As shown in FIG. 10, the elevation coils 16 a and 16 b are sandwiched between the magnets 79 a and 79 b fixed to the yoke 68 and the yoke 55. Since the mechanism of operation of the elevation coil 16a and the magnet 79a is the same as that of the elevation coil 16b and the magnet 79b, the explanation will be made here on the side of the elevation coil 16a and the magnet 79a.

  The polarity of the magnet 79a is as shown in FIG. The boundary of the magnetic pole is shown by a broken line for easy understanding. The boundary portion of an actual magnet is a neutral region having no magnetic pole with a width of 0.2 to 0.4 mm.

  Magnetic fields in the directions of arrows 119 and 120 reach the sides 117 and 118 of the elevation coil 16a. The magnetic flux emitted from the magnet 79a as indicated by the arrow 119 enters the yoke 55, travels through the yoke 55 as indicated by the arrow 121, and returns to the magnet 79a as indicated by the arrow 120. Further, a part returns to the magnet 79 a without going to the yoke 55 as indicated by the arrow 122.

  Since the direction of the current flowing through the sides 117 and 118 of the elevation coil 16a is opposite and the direction of the magnetic field 119 and 120 reaching is also opposite, the direction of the generated force is the same. The direction of the force is the Y direction perpendicular to the direction of the current and the direction of the magnetic field.

  The force in the X direction is generated on the remaining sides of the elevation coil 16a, that is, the sides 123 and 124 shown in FIG. 11, but the direction of the force received from the magnetic field indicated by the arrows 119 and 120 is reversed and cancels. It does not move in the direction.

  The holder 20 is not covered on the magnet 79a side of the elevation coil 16a, but this cuts the space for placing the holder 20, brings the elevation coil 16a closer to the magnet 79a, and reduces the distance 125 therebetween. Because. Although the yoke 55 is disposed on the Z + side of the elevation coil 16a, but the magnet 79a is not disposed, the magnetic field strength is greater on the side closer to the magnet 79a and on the Z− side. When the distance 125 is reduced, a larger force can be received from the magnetic field with the same current, and power consumption can be reduced.

  Similarly, a force in the Y direction is generated for the elevation coil 16b. They are connected in series so that the forces in the Y direction generated by the elevation coils 16a and 16b are in the same direction. Thus, by passing a current through the elevation coils 16a and 16b, the movable portion 27 and the lens 5 attached thereto can be moved in the Y direction.

  The azimuth coil 15 and the azimuth magnet 78 also generate a force in the X direction in the same manner, just by switching the relationship between the X direction and the Y direction. Thereby, by passing an electric current through the azimuth coil 15, the movable part 27 and the lens 5 attached thereto can be moved in the X direction.

  As described above, the position of the movable portion 27 is obtained by receiving the light passing through the slits 24a and 24b of the movable portion 27 by the position sensors 81a and 81b, and the movement of the movable portion 27 based on the position information. Is done.

  In the first embodiment, as shown in FIG. 5, the light emitting diode 47 is on the Z + side with respect to the position sensors 81a and 81b. Therefore, the light receiving surfaces 85a and 85b of the position sensors 81a and 81b facing the direction of the light emitting diode 47 are facing the Z + direction and are located on the Z + side with respect to the Z axis with respect to the incident surface 86 of the lens 5. is doing. With such a configuration, it is possible to prevent the irradiation laser light from the laser diode 1 from entering the position sensors 81a and 81b. This will be described in detail below with reference to FIG. Since the functions of the position sensors 81a and 81b are the same, the position sensors 81a and 81b will be described as the position sensor 81 and the light receiving surfaces 85a and 85b will be described as the light receiving surface 85.

  The light receiving surface 85 of the position sensor 81 faces the direction of the light emitting diode 47 on the Z + side. However, when the light receiving surface 85 is located on the Z-side with respect to the Z axis from the incident surface 86 of the lens 5 as shown in FIG. 15A, a part of the light 126 from the laser diode 1 is incident on the lens 5. It is conceivable that the light is reflected at 86 and travels like an optical path 127. In this case, the light 126 from the laser diode 1 enters the light receiving surface 85 of the position sensor 81.

  On the other hand, in the configuration of the first embodiment shown in FIG. 15B, the light receiving surface 85 of the position sensor 81 faces the direction of the light emitting diode 47 on the Z + side further than that, and the incident surface of the lens 5 86 on the Z + side with respect to the Z axis. That is, the light receiving surface 85 is perpendicular to the optical axis direction of the lens 5 and faces the exit surface 201 side of the lens 5, and the position on the exit surface 201 side of the lens 5 with respect to the entrance surface 86 of the lens 5 with respect to the optical axis direction of the lens 5. Is provided. According to such a configuration, even if a part of the light 126 from the laser diode 1 is reflected by the incident surface 86 of the lens 5 and travels like the optical path 127, the optical path 127 is more Z than the incident surface 86 of the lens. Since it is on the minus side, the light 126 does not enter the light receiving surface 85 of the position sensor 81 on the Z + side.

  As described above, since the light from the laser diode 1 does not enter the position sensor 81, the position detection by the position sensor 81 is performed only by the light from the light emitting diode 47. Therefore, accurate position detection is performed. It can be carried out. Further, the laser diode 1 is intermittently lit for distance measurement, but this light can also prevent the position signal from appearing in the form of noise, which makes it impossible to accurately detect the position, or the lens 5 is shaken. It can be prevented from moving.

  FIG. 15C is a diagram for explaining a modification of the first embodiment. In the first embodiment described above, since the light emitting diode 47 is on the Z + side, the position of the light receiving surface 85 of the position sensor 81 facing the light emitting diode 47 side is relative to the Z axis with respect to the incident surface 86 of the lens 5. It was on the Z + side. On the other hand, as shown in FIG. 15C, the light emitting diode 47 is positioned on the Z− side of the position sensor 81, and the light receiving surface 85 of the position sensor 81 faces the Z− side where the light emitting diode 81 exists. There may be. In this case, the light receiving surface 85 of the position sensor 81 may be arranged on the Z− side with respect to the Z axis with reference to the emission surface 201 of the lens 5. That is, in this configuration, the light receiving surface 85 is perpendicular to the optical axis direction of the lens 5 and faces the incident surface 86 side of the lens 5, and the incident surface of the lens 5 with respect to the exit surface 201 of the lens 5 with respect to the optical axis direction of the lens 5. It is arranged at a position on the 86 side.

  According to such a configuration, stray light due to outside light that is not used among the light emitted from the laser diode 1 emitted from the emission surface 201 of the lens 5 can be prevented from entering the position sensor 81, thereby The same effect as described in the above can be obtained.

  In the present embodiment, the wall 128 of the convex portion 90 of the main body 89 has a rough surface. As shown in FIG. 15D, a part of the light 129 from the laser diode 1 is reflected by the incident surface 86 of the lens 5, travels like an optical path 130, and hits the wall 128. However, since the wall 128 has a rough surface 133, it is irregularly reflected here, and the light hitting the wall 128 does not cause a problem. On the other hand, when the rough surface 133 is not formed, the light 129 is reflected by the wall 128 and travels along the optical path 131. Further, the light 129 is reflected by the holder 20 provided with the slit 24, travels along the optical path 132, and enters the light receiving surface 85 of the position sensor 81.

  By making the portion of the wall 128 where the light 128 reflected by the lens 5 hits the rough surface 133, the reflected light 128 is prevented from entering the position sensor 81, and as described above, Accurate position detection can be performed.

  Various forms can be considered as the rough surface 133. However, if the surface has unevenness of 0.1 mm or more, light can be diffusely reflected, and a better effect can be obtained. In addition, the rough surface 133 may be formed by a surface in which concave and convex grooves of 0.1 mm or more are continuous, which makes it easier to diffusely reflect light and obtain a better effect.

(Second Embodiment)
FIG. 16 shows a second embodiment of the present invention and is a partial cross-sectional view corresponding to FIG. The same parts as those in the first embodiment are indicated by the same numbers.

  In the present embodiment, the configuration of the mounting portion of the lens 5 of the movable portion 27 and the convex portion 97 portion extending in the Z + direction from the convex portion 90 of the main body 89 (FIG. 2) are different from those of the first embodiment.

  In the movable portion 27, the mounting portion of the holder 5 and the lens 5 of the holder 20 has a convex shape in the Z-direction, and the lens 5 is fixed to a position that is further convex in the Z-direction than the holder 20.

  On the other hand, a convex portion 97 extending in the Z + direction from the convex portion 90 of the main body 89 is provided with a concave portion 134 at the light exit 108 portion from the laser diode 1, and the lens 5 enters the portion. No. 5 entrance surface 86 is completely contained. At the time of assembly, the biaxial actuator 87 may be combined with the main body 89 in such a manner that the biaxial actuator 87 is slid from the Z + direction, and even if the lens 5 enters the recess 134, the assembly is not impossible.

  Other configurations and operations are substantially the same as those in the first embodiment.

  In the present embodiment, as described in the first embodiment, the laser light emitted from the laser diode 1 is transmitted through the hole 93, the lens frame 98, the hole 93, the hole 107 in the convex portion 90 of the main body 89, A cover 200 is provided up to just before the lens 5 so as to go through the hole 95 and go out for the first time at the exit 108. Further, a recess 134 is provided at the exit portion, and the lens 5 enters the portion, and the cover 200 and the lens 5 overlap in the Z direction. Thereby, the laser beam does not leak directly to the outside up to the incident surface 86 of the lens 5, and the reflected light from the incident surface 86 does not leak directly to the outside. In addition, although the light reflected by the incident surface 86 and the light to the incident surface 86 may be repeatedly reflected and leaked, the intensity of the light is attenuated by repeating the reflection. Thereby, it is possible to prevent the light from the laser diode 1 from entering the position sensors 81a and 81b, and to perform accurate position detection based on the light from the light emitting diode 47. In addition, it is possible to prevent a signal such as noise from appearing in the position signal due to intermittent lighting of the laser diode 1 for distance measurement.

  As described in the first embodiment, if the surface 135 to which the reflected light of the incident surface 86 of the lens 5 hits is a rough surface, the light that leaks through repeated reflection can be further weakened, and the position signal can be improved. Can be.

(Third embodiment)
FIG. 17 shows a third embodiment of the present invention and is a partial cross-sectional view corresponding to FIG. The same parts as those in the first embodiment are indicated by the same numbers.

  In the present embodiment, the configuration of the lens 5 mounting portion of the movable portion 27 and the convex portion 97 portion extending from the convex portion 90 of the main body 89 in the Z + direction are different from those of the first embodiment.

  In the movable portion 27, the holder 20 has a convex shape in the Z− direction, and the tip 136 of the holder 20 has a convex shape in the Z− direction from the incident surface 86 of the lens 5. In the Z direction, the lens 5 is covered with the holder 20.

  On the other hand, a convex portion 97 extending in the Z + direction from the convex portion 90 of the main body 89 is provided with a concave portion 134 at the light exit 108 portion from the laser diode 1, and the tip 136 of the holder 20 enters the portion. Yes. At the time of assembly, the biaxial actuator 87 may be combined with the main body 89 in such a manner that the biaxial actuator 87 is slid from the Z + direction, and even if the tip 136 of the holder 20 enters the recess 134, the assembly is not impossible.

  Other configurations and operations are substantially the same as those in the first embodiment.

  In the present embodiment, as described in the first embodiment, the laser light emitted from the laser diode 1 is transmitted through the hole 93, the lens frame 98, the hole 93, the hole 107 in the convex portion 90 of the main body 89, A cover 200 is provided up to just before the lens 5 so as to go through the hole 95 and go out for the first time at the exit 108. Furthermore, the exit part is provided with a recess 134, and the tip 136 of the holder 20 enters the part, and the cover 200 and the wall part 20-1 of the holder 20 overlap in the Z direction. Thereby, the laser beam does not leak directly to the outside up to the incident surface 86 of the lens 5, and the reflected light from the incident surface 86 does not leak directly to the outside. In addition, although the light reflected by the incident surface 86 and the light to the incident surface 86 may be repeatedly reflected and leaked, the intensity of the light is attenuated by repeating the reflection. Thereby, it is possible to prevent the light from the laser diode 1 from entering the position sensors 81a and 81b, and to perform accurate position detection based on the light from the light emitting diode 47. In addition, it is possible to prevent a signal such as noise from appearing in the position signal due to intermittent lighting of the laser diode 1 for distance measurement.

  As described in the second embodiment, if the surface 135 to which the reflected light of the incident surface 86 of the lens 5 hits is a rough surface, the light that leaks through repeated reflections can be further weakened, and the position signal can be improved. Can be.

(Fourth embodiment)
18 to 20 are views showing a fourth embodiment of the present invention. FIG. 18 is a partial cross-sectional view corresponding to FIG. 5, and FIG. 19 is a three-plane view of the position sensor portion of the main part. 20 is a diagram showing a modification. The same parts as those in the first embodiment are indicated by the same numbers.

  In the present embodiment, the configuration of the position sensors 81a and 81b is different from that of the first embodiment. In the first embodiment, the position sensors 81a and 81b are attached as they are to the substrate 80. However, in this embodiment, covers 137a and 137b manufactured by bending a brass plate are attached.

  Here, the cover 137b will be described in detail with reference to FIG. 19A to 19C are three views, but FIG. 19C is a cross section. The cover 138a is also the same.

  A hole 138 is provided in a surface of the cover 137b that covers the light receiving surface 85b of the position sensor 81b. Thereby, the light of the light emitting diode 47 can be incident on the light receiving element body 142 in the position sensor 81b.

  The cover 137b is provided with bent portions 139a to 139d, and covers a part of the side surface of the position sensor 81b while being bent at these portions. In the bent portions 139a and 139c, solders 143a and 143b are fixed to the common terminals 141b and 141c of the position sensor 81b by soldering, and the cover 137b is fixed to the position sensor 81b by the solders 143a and 143b. The remaining terminals 141a and 141d are provided with reliefs 140a and 140b at the bent portions 139a and 139c so as not to be short-circuited by the cover 137b.

  Other configurations and operations are substantially the same as those in the first embodiment.

  The leakage light of the laser light emitted from the laser diode 1 is transmitted to the light receiving element main body 142 in the position sensor 81b not only from the light receiving surface 85b of the position sensor 81b but also from the side as indicated by an arrow 144 in FIG. So that it is incident. In the present embodiment, a laser emitted from the laser diode 1 as indicated by an arrow 144 is formed by covering all or part of the position sensor 81b other than the portion through which light is transmitted to the light receiving element body 142 with the cover 137b. Light leakage light can be prevented from entering the light receiving element body 142. The same applies to the position sensor 81a.

  Thereby, it is possible to prevent the light from the laser diode 1 from entering the position sensors 81a and 81b, and to perform accurate position detection based on the light from the light emitting diode 47. In addition, it is possible to prevent a signal such as noise from appearing in the position signal due to intermittent lighting of the laser diode 1 for distance measurement.

  In the present embodiment, the leakage light of the laser light emitted from the laser diode 1 by the covers 137a and 137b can be reduced to the position sensors 81a and 81b, so that the incident surface 86 of the lens 5 and the position sensors 81a and 81b It is not always necessary to pay attention to the positional relationship in the Z direction between the light receiving surfaces 85a and 85b, and the light receiving surfaces 85a and 85b of the position sensors 81a and 81b may be in the Z-direction from the incident surface 86 of the lens 5.

  In the present embodiment, the brass covers 137a and 137b are soldered to the common terminals of the position sensors 81a and 81b to be fixed and connected. As a result, the brass covers 137a and 137b are dropped to the reference voltage, and the noise jumping into the position sensors 81a and 81b in the form of electrostatic coupling from the external wiring portion can be reduced. Position detection can be performed.

  The same effect can be obtained by connecting the brass covers 137a and 137b to the ground. A ground pattern may be prepared on the substrate to which the position sensors 81a and 81b are soldered, and a cover may be soldered to the portion and fixed.

  In the present embodiment, the cover covers 137a and 137b are made of brass, but may be made of other metals or synthetic resins. In the case of a synthetic resin, since the degree of freedom in shape is high, the design that covers the position sensors 81a and 81b without gaps and further reduces the incidence of laser light becomes easy.

  The cover member may hold the position sensor instead of the substrate, and the wiring may be performed by an electric wire or a flexible substrate. By also serving as a holding member for the position sensor, the number of parts can be reduced, and the price and size can be reduced.

  Further, as shown in FIGS. 20A and 20B, an annular metal frame 145 may be attached to the substrate 80, and a black silicone adhesive 146 may be filled therein. The annular metal frame 145 is provided with a land on the substrate 80 and soldered or bonded and fixed.

  The metal frame 145 alone can prevent the laser light from the direction of the arrow 147 from entering the position sensor 81b, but filling the silicone adhesive 146 prevents the laser light from entering as indicated by the arrow 148. be able to. Further, the silicone adhesive 146 can cover and shield the position sensor 81b from surroundings without generating a fine gap. As a result, it is possible to better prevent leakage light from entering the position sensor 81b, and to perform more accurate position detection. Workability is good when the material to be filled is a silicone adhesive, but any resin that blocks or attenuates laser light may be used, even if it is not a silicone adhesive.

(Fifth embodiment)
FIG. 21 is a diagram showing a fifth embodiment of the present invention, and FIG. 21 is a partial cross-sectional view corresponding to FIG. The same parts as those in the first embodiment are indicated by the same numbers.

  In the present embodiment, the configuration of the position sensors 81a and 81b and the light emitting diode 47 are different from those of the fourth embodiment. In the present embodiment, a light emitting diode 47 that emits red light having a wavelength of 650 nm is used instead of infrared light. Correspondingly, the position sensors 81a and 81b are 320 to 1100 nm and have sensitivity to red light in addition to infrared rays. Further, in the present embodiment, filters 149a and 149b are sandwiched between the covers 137a and 137b and the light receiving surfaces 85a and 85b of the position sensors 81a and 81b. The filters 149a and 149b are low-pass filters that have high transmittance of light of 760 nm or less and transmit red light but do not transmit infrared light. On the other hand, the wavelength of the laser diode 1 remains at 870 nm.

  Other configurations and operations are almost the same as those in the fourth embodiment.

  According to the present embodiment, even if the leakage light of the laser diode 1 attempts to enter the light receiving surfaces 85a and 85b, the laser light having a wavelength of 870 nm is attenuated by the filters 149a and 149b and does not enter. On the other hand, the light of the light emitting diode 47 having a wavelength of 650 nm is incident after passing through the filters 149a and 149b.

  Thereby, the light from the laser diode 1 can be prevented from entering the position sensors 81 a and 81 b, and the accurate position detection can be performed based on the light from the light emitting diode 47. In addition, it is possible to prevent a signal such as noise from appearing in the position signal due to intermittent lighting of the laser diode 1 for distance measurement. Since unnecessary light from the laser diode 1 is cut immediately before the position sensors 81a and 81b by the filters 149a and 149b, a higher effect can be expected as compared with the method up to the fourth embodiment.

  The light shielding as shown in FIG. 20 shown as a modified example in the fourth embodiment is used together to completely cover the position sensors 81a and 81b except for the portions where the filters 149a and 149b are attached, and the light is filtered by the filters 149a and 149b. It is also possible to enter only through the.

  In this case, the light from the laser diode 1 can be almost completely blocked from entering the position sensors 81a and 81b. Accordingly, accurate position detection can be performed based on the light from the light emitting diode 47, and mixing of noise into the signal can be prevented. When the output of the laser diode 1 is large, the level of leakage light also increases, and in such a case, such a method is necessary.

  In the present embodiment, the filters 149a and 149b are fixed in front of the light receiving surfaces 85a and 85b of the position sensors 81a and 81b. However, coating may be applied directly to the corresponding portions of the packages of the position sensors 81a and 81b.

  In the present embodiment, the wavelength of the laser diode is cut by a filter because a wide range of wavelengths from the infrared region to the visible region is used for the sensitivity of the position sensors 81a and 81b. However, if the wavelength of the position sensors 81a and 81b is in the red range only, the filter is not necessary.

  Regarding the wavelength, if there is a corresponding position sensor or light emitting diode, a different color such as orange may be used instead of red. However, since the laser diode is invisible and wants to project, it is preferable to emit infrared rays, and the red color of the light emitting diode is easy to obtain and can be made inexpensive.

  As described above, the present invention is not limited to the above-described embodiment, and can be variously modified. There are various arrangements of magnets and coils. For example, although the magnet is opposed to one side of the azimuth coil and the elevation coil, the magnet may be disposed on both sides and the coil may be sandwiched between the magnets. Although one light emitting diode is used to enter light into two slits, one light emitting diode may be prepared for each slit. Further, the light emitting diode may be made small, and the light emitting diode may be mounted on the movable part.

  The optical system is not limited to this configuration but can be applied to various optical systems. The laser beam emitted from the lens is received by another lens different from the emitted lens. However, the laser beam is received again by the same lens, and the received light is separated and detected by, for example, an optical path dividing element. The present invention can also be applied to a configuration that serves as both a laser scanning device and a light receiving device.

  Moreover, the structure which moves other optical elements instead of a lens may be sufficient. At this time, the transmissive type of the optical element is more likely to cause unexpected reflection on the surface, so that the effects of the present invention can be better enjoyed. As the transmissive optical element, an element using the above-described lens or diffraction grating is suitable for constituting a laser scanning apparatus, and an apparatus having good optical performance can be obtained.

FIG. 1 is a perspective view (No. 1) of a laser scanning apparatus of the present invention. FIG. 2 is a perspective view (No. 2) of the laser scanning device of the present invention. FIG. 3 is a perspective view (No. 3) of the laser scanning apparatus of the present invention. 4 is a cross-sectional perspective view of the entire laser scanning device when cut along line AA in FIG. FIG. 5 is a cross-sectional view of the entire laser scanning apparatus taken along line AA in FIG. FIG. 6 is a cross-sectional view of the entire laser scanning device taken along line BB in FIG. FIG. 7 is an exploded perspective view of the entire laser scanning device when cut along line BB in FIG. FIG. 8 is a perspective view (No. 1) of the two-axis actuator unit set constituting the laser scanning device. FIG. 9 is a perspective view (No. 2) of the two-axis actuator part group constituting the laser scanning device. 10 is a cross-sectional view of the entire biaxial actuator section taken along line CC in FIG. FIG. 11 is an exploded perspective view (part 1) of the two-axis actuator unit set. FIG. 12 is an exploded perspective view (part 2) of the two-axis actuator unit set. FIG. 13 is an exploded perspective view of a spring receiving portion set constituting the biaxial actuator portion set. FIG. 14 is a diagram illustrating a usage example of the in-vehicle distance measuring device using the laser scanning device according to the first embodiment. FIG. 15 is a diagram for explaining a configuration that is a feature of the first embodiment. FIG. 16 is a diagram showing the configuration of the second exemplary embodiment of the present invention. FIG. 17 is a diagram showing the configuration of the third exemplary embodiment of the present invention. FIG. 18 is a diagram showing the configuration of the fourth exemplary embodiment of the present invention. FIG. 19 is a three-side view of the position sensor portion of the main part. FIG. 20 is a diagram showing a modification of the fourth embodiment. It is a figure which shows the 5th Embodiment of this invention.

Explanation of symbols

1 Laser diode 5 Scan lens (lens)
7, 20 Holder 47 Light emitting diode 81 (81a, 81b) Position sensor 85 (85a, 85b) Light receiving surface 86 Incident surface 97 Convex portion 200 Cover 201 Output surface

Claims (7)

An optical element; a holder that holds the optical element; a support means that supports the holder so as to be movable in a direction perpendicular to the optical axis of the optical element; and a first laser that emits laser light incident on the optical element. Ranging for in-vehicle provided with a light emitting element, a position detection sensor for detecting the position of the center of gravity of light for detecting the position of the holder, and a second light emitting element for emitting light incident on the position detection sensor A laser scanning device used in the apparatus,
The light-receiving surface of the position detection sensor is (1) perpendicular to the optical axis direction of the optical element and facing the exit surface side of the optical element, and with respect to the incident surface of the optical element with respect to the optical axis direction of the optical element. Or (2) the optical element that is perpendicular to the optical axis direction of the optical element and faces the incident surface side of the optical element, with respect to the optical axis direction of the optical element. The laser scanning device is arranged at a position on the incident surface side of the optical element with reference to the exit surface of the optical element . 2. The laser scanning apparatus according to claim 1, wherein light from the first light emitting element is reflected by a surface of the optical element and then irradiated to a rough surface causing irregular reflection . 3. The laser scanning apparatus according to claim 2, wherein the rough surface is a continuous surface having irregularities of 0.1 mm or more . 3. The laser scanning apparatus according to claim 2, wherein the rough surface is a groove having irregularities of 0.1 mm or more . The laser scanning apparatus according to claim 1, wherein the optical element transmits light . The laser scanning device according to claim 5 , wherein the optical element is a lens . 6. The laser scanning device according to claim 5, wherein the optical element is a diffraction grating .

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