JP3776521B2 - Optical scanner - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a compact optical scanner that reflects light from a light source and scans the reflected light in one and two dimensions.
[0002]
[Prior art]
<First prior art>
Conventionally, as an example of a small optical scanner, it has a vibration input unit in which a scanning unit for reflecting light, an elongated elastic deformation unit, and a piezoelectric actuator are bonded, and the piezoelectric actuator is used to vibrate the reflecting unit in two dimensions. Those that scan are known.
[0003]
Such an optical scanner is disclosed in, for example, Japanese Patent Application Laid-Open No. 5-100195.
[0004]
FIG. 14 shows the configuration of the optical scanner 1 disclosed in Japanese Patent Laid-Open No. 5-100175.
[0005]
The optical scanner 1 includes a thin plate 6 and a piezoelectric actuator 21.
[0006]
The plate 6 is integrally formed with a vibration input portion 5, an elastic deformation portion 2, a scanning portion 3, and a weight portion 3W.
[0007]
The piezoelectric actuator 21 has a structure in which a strain transducer 23 is joined to a laminated piezoelectric element 22.
[0008]
The scanning unit 3 is formed with a mirror surface 4 for reflecting the light beam.
[0009]
In the optical scanner 1 configured as described above, when a voltage is applied to the piezoelectric actuator 21 bonded to the vibration input unit 5 to vibrate the vibration input unit 5, the elastic deformation unit 2 resonates and the scan unit 3 In FIG. 1A, the angle θ around the axis P _T In FIG. 1B, the angle θ around the axis Q is rotated. _B It will turn in the range of.
[0010]
In this case, by deforming the vibration input unit 5 from the piezoelectric actuator 21 in a vibration mode in which vibrations having a resonance frequency in the torsional deformation mode and vibrations having a resonance frequency in the bending deformation mode are superimposed, the deformation elastic part 2 Thus, the torsional deformation mode and the bending deformation mode are amplified, and the scanning unit 3 becomes a vibration in which the torsional vibration and the bending vibration are combined.
[0011]
In the optical scanner 1 configured as described above, two-dimensional optical scanning is realized by controlling the voltage applied to the piezoelectric actuator 21 by a drive circuit (not shown).
[0012]
<Second prior art>
Also, as an example of a small optical scanner, there is known an optical deflector that uses a silicon semiconductor substrate and a torsion spring and that scans light by swinging a reflecting mirror by electromagnetic force.
[0013]
Such an optical scanner is disclosed in, for example, the document “TECHNICAL DIGEST OF THE SENSOR SYMPISOUM, 1995.pp17-20”.
[0014]
FIG. 15 shows the configuration of the optical scanner disclosed in this document.
[0015]
In this optical scanner, a reflecting mirror 34, a torsion spring 33, and a fixed frame 50 that supports these are integrally formed on a silicon semiconductor substrate 31 as an optical deflector.
[0016]
A planar coil 35 is laid on the peripheral edge of the reflecting mirror 34, and the planar coil 35 is electrically connected to the electrode 36 formed on the fixed frame 50 through the torsion spring 33. .
[0017]
In addition, the circular permanent magnet 38 is disposed at a location where the magnetization direction is parallel to the reflecting mirror 34 and about 45 degrees with the axial direction of the torsion spring 33 via the spacer insulating substrate 40. .
[0018]
A Lorentz force is generated in the planar coil 35 to which an alternating current is applied by an interaction with the magnetic field generated by the permanent magnet 38.
[0019]
By this Lorentz force, the reflecting mirror 34 swings in the torsion direction of the torsion spring 33.
[0020]
When a current having the same frequency as the resonance frequency defined by the elastic characteristics of the torsion spring 33 and the mass and center of gravity of the reflecting mirror 34 is applied to the planar coil 35, the maximum amplitude of the current value can be obtained.
[0021]
Here, the damping coefficient is reduced by vacuum-sealing the reflecting mirror 34.
[0022]
In FIG. 15, reference numeral 39 is a gas adsorbent, 41 is a front cover insulating substrate, and 42 is a back insulating substrate.
[0023]
[Problems to be solved by the invention]
However, the above-described first and second prior arts do not describe the viewpoints of durability of electrical elements such as the wiring of an optical scanner that vibrates with a large deflection angle and protection from the atmosphere.
[0024]
Accordingly, the present invention pays attention to such a point, and an object of the present invention is to provide an optical scanner having an electric element exhibiting high durability in an optical scanner that vibrates with a large deflection angle.
[0025]
[Means for Solving the Problems]
According to the first aspect of the present invention, the support for fixing to an arbitrary member, the movable plate at least one of which is a reflecting surface that reflects light, and the center of the movable plate with respect to the width direction are removed. An elastic member that connects the support and the movable plate, a drive coil formed on the movable plate, and a permanent magnet disposed at a distance in the vicinity of a tip portion of the movable plate; By applying an alternating current to the drive coil, the movable plate performs bending and torsional vibration with the connecting portion between the elastic member and the support as a fixed end, and the elastic member is disposed inside There is provided an optical scanner having an electric element and an insulating elastic film reaching the movable plate and the support.
[0026]
According to claim 2 of the present invention, a support for fixing to an arbitrary member, a movable plate having at least one surface reflecting light, and elasticity for connecting the support and the movable plate. A plurality of drive coils formed on the movable plate along the width direction of the movable plate; and permanent magnets arranged at intervals in the vicinity of the movable plate. By applying an alternating current to the optical scanner, the movable plate performs bending and torsional vibration with the connecting portion between the elastic member and the support as a fixed end, and the elastic member has an electric element inside. And an insulating organic elastic film that reaches the movable plate and the support.
[0027]
According to claim 3 of the present invention, a support for fixing to an arbitrary member, a movable plate having at least one surface reflecting light, and elasticity for connecting the support and the movable plate. A member, a drive coil formed on the movable plate, and a permanent magnet disposed in the vicinity of the front end portion and the side wall portion of the movable plate with an interval therebetween, and an alternating current is supplied to the drive coil. When applied, the movable plate is an optical scanner that performs bending and torsional vibration with the connecting portion between the elastic member and the support as a fixed end, and the elastic member has an electric element therein, An optical scanner is provided that is an insulating organic elastic film reaching the movable plate and the support.
[0028]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0029]
<First embodiment>
1 to 4 show a first embodiment of an optical scanner according to the present invention and a modification thereof.
[0030]
The optical scanner of this embodiment can perform two-dimensional light scanning. A perspective view of this optical scanner is shown in FIG. 1, and a driving coil used here is shown in FIG. A cross-sectional view of this optical scanner is shown in FIG. 2 (b), and the manufacturing process of this optical scanner is shown in FIGS. 3 (a) to 3 (e) and FIGS. 4 (a) to 4 (d).
[0031]
The optical scanner according to the first embodiment is configured as follows.
[0032]
This optical scanner includes a movable plate 101, an elastic member 102, a support body 103, a permanent magnet 104, and a drive coil 106.
[0033]
The movable plate 101 is formed with a reflecting surface 105 for reflecting light, and the back surface of the movable plate 101 in FIG.
[0034]
Since the main material used for the movable plate 101 is desired not to deform the reflecting surface 105 during vibration, single crystal silicon, which is a highly rigid material, is used here as the main material of the movable plate 101.
[0035]
In addition, other materials such as silicon nitride, aluminum, and polyimide are used as the material for the movable plate 101.
[0036]
That is, the silicon nitride is used as a mask material when manufacturing an optical scanner, and the aluminum is used as the wiring of the driving coil 106 and the contact pad 107 at the starting point and the ending point of the driving coil 106, and in some cases, the reflective surface 105. Used as a mirror material.
[0037]
Further, the polyimide is used to form a film that sandwiches the drive coil 106 from above and below, so that insulation between the coil wiring and electrical elements including the contact pads 107 are not exposed to the atmosphere. .
[0038]
The elastic member 102 has a polyimide film extending from the movable plate 101 as a main material, and wiring 108 extending from the contact pad 107 to the support body 103 is formed therein.
[0039]
Aluminum is used as the material of the wiring 108.
[0040]
The support 103 is used as an adhesive portion for fixing the optical scanner to die cast or the like, and a bonding pad 109 for supplying electric power from the outside to the drive coil 106 through the wiring 108 is formed on the surface. Has been.
[0041]
This support 103 uses single crystal silicon as a main material, and since this single crystal silicon has high rigidity, it is convenient for fixing to die-casting or the like.
[0042]
In addition, the support 103 is not exposed to the atmosphere by sandwiching silicon nitride as a mask material when manufacturing an optical scanner, aluminum for forming the bonding pad 109 and the wiring 108, and the wiring 108 from above and below. For this purpose, a polyimide film or the like is used.
[0043]
As the polyimide film, a polyimide film extending from the movable plate 101 and the elastic member 102 is used.
[0044]
The single crystal silicon of the support 103 and the single crystal silicon used in the movable plate 101 are formed from the same substrate.
[0045]
As shown in FIG. 2A, the drive coil 106 has a wiring formed in parallel with the width direction in the vicinity of the permanent magnet 104 while changing the line width of the wiring and the distance between the wirings on each side. However, compared with wiring formed in other places, the line width of the wiring is narrow and the interval between the wirings is also narrowed.
[0046]
However, the thickness of the drive coil 106 is made uniform.
[0047]
Here, with respect to the arrangement position of the permanent magnet 104, the configuration shown in the above-mentioned document “TECHNICAL DIGEST OF THE SENSOR SYMPOSIUM, 1995.pp17-20” is applied, and the magnetization direction is set in the plate thickness direction of the movable plate 101. In addition, the permanent magnet 104 is disposed at a position where the lower end or upper end of the permanent magnet 104 is aligned with an extension line of about 45 degrees above or below the drive coil 106 at the tip of the movable plate 101.
[0048]
Next, a method for manufacturing the optical scanner according to the first embodiment will be described.
[0049]
This optical scanner can be manufactured by a semiconductor manufacturing technique as shown in the cross-sectional view of FIG. 2B, FIGS. 3A to 3E, and FIGS. 4A to 4D. There are only four types of materials used: single crystal silicon substrate, silicon nitride, polyimide and aluminum.
[0050]
First, as shown in FIG. 3A, the silicon substrate 110 is cleaned, and a silicon nitride film 111 is formed on both surfaces of the silicon substrate 110 by using a low-pressure CVD apparatus.
[0051]
Since the silicon nitride films 111 formed on both surfaces of the silicon substrate 110 are used as a mask material when the movable plate 101 and the support 103 are separated, as shown in FIG. In 111, a portion where silicon is removed is patterned by fluorine-based dry etching.
[0052]
Next, as shown in FIG. 3C, a first polyimide layer 112 is formed on the silicon nitride film 111 on the surface opposite to the patterned surface.
[0053]
As a method for forming the first polyimide layer 112, a method is used in which a liquid polyimide solution is applied onto the silicon nitride film 111, uniformly formed by a printing method or a spin coating method, and sintered.
[0054]
Next, as shown in FIG. 3D, the drive coil 106 and the contact pad 107 are formed by etching the aluminum sputtered on the first polyimide layer 112.
[0055]
Next, as shown in FIG. 3 (e), the second polyimide layer 113 is coated with a liquid polyimide solution on the first polyimide layer 112 in the same manner as the first polyimide layer 112 described above, and is printed. Alternatively, the film is uniformly formed by spin coating and sintered.
[0056]
At this time, the polyimide on the contact pad 107 is removed in advance.
[0057]
Next, as shown in FIG. 4A, the wiring 108 is formed by etching the aluminum sputtered on the second polyimide layer 113.
[0058]
Next, as shown in FIG. 4B, in order to ensure the contact between the drive coil 106 and the wiring 108 in the contact pad 107 and to form the bonding pad 109, aluminum is further formed by sputtering and etched. Then, patterning is performed.
[0059]
At this time, it is desirable that the aluminum film is considerably thicker than the wiring 108.
[0060]
Next, as shown in FIG. 4C, a third polyimide layer 114 is formed for the purpose of determining the rigidity of the elastic member 102 and protecting the bonding pad 109 from the atmosphere.
[0061]
After the third polyimide layer 114 is formed, the polyimide on the bonding pad 109 is removed by photolithography and dry etching.
[0062]
Next, as shown in FIG. 4D, anisotropic etching of silicon is performed from the back surface of the silicon substrate 110 using an alkaline solution in order to produce the movable plate 101 and the support 103 from the silicon substrate 110.
[0063]
At this time, as shown in FIG. 2B, there is a silicon nitride film 111 under the first polyimide layer 112 that becomes the elastic member 102, and this silicon nitride film 111 is formed when the silicon substrate 110 is etched through. It becomes a protective layer for protecting the first polyimide layer 112.
[0064]
In addition, after the through etching of the silicon substrate 110, the silicon nitride film 111 exposed on the back surface of the elastic member 102, the movable plate 101, and the support 103 is removed by dry etching.
[0065]
Then, if necessary, the optical scanner according to the first embodiment is completed by sputtering aluminum to form a reflective surface 105 having a high reflectivity.
[0066]
Next, the operation of the optical scanner according to the first embodiment will be described.
[0067]
First, by applying an alternating current from the bonding pad 109, a Lorentz force is generated in the drive coil 106 that circulates the tip of the movable plate 101 by the interaction with the permanent magnet 104.
[0068]
The vector direction of the Lorentz force is determined by the positional relationship between the permanent magnet 104 and the drive coil 106. In this case, a force is generated in the thickness direction of the movable plate 101.
[0069]
In this optical scanner, since the connecting portion between the elastic member 102 and the movable plate 101 is off the center with respect to the width direction of the movable plate 101, it is not possible to create only bending vibration, and bending vibration and torsional vibration occur simultaneously. It has a structure to do.
[0070]
Here, the vibration of the elastic member 102 in the plate thickness direction with the connecting portion with the support body 103 as a fixed end is called bending vibration, and the movable plate 101 rotates upward or downward with the central axis of the elastic member 102 as the rotation axis. The vibration that works in the direction to do is called torsional vibration.
[0071]
In this case, the amplitude of the movable plate 101 due to the bending vibration is such that the Lorentz force generated in the drive coil 106 and the perpendicular line from the point where the Lorentz force is generated to the side connected to the elastic member 102 of the support 103. Determined by product with length.
[0072]
Further, in the case of the amplitude of the movable plate 101 due to torsional vibration, the strength of the Lorentz force generated in the drive coil 106 and the length of the perpendicular from the point where the Lorentz force is generated to the central axis with respect to the width direction of the elastic member 102 Determined by the product of
[0073]
The Lorentz force is determined by the performance and size of the permanent magnet 104, the number of turns of the drive coil 106, the wiring length, the amount of current applied to the drive coil 106, and the distance from the permanent magnet 104 to the drive coil 106.
[0074]
Here, the reason why the drive coil 106 is formed so as to go around the outermost periphery of the movable plate 101 is to increase the amount of generated force as much as possible.
[0075]
Then, by fixing the support 103 to a die cast (not shown) and applying a current to the drive coil 106, the movable plate 101 starts to vibrate with the boundary between the support 103 and the elastic member 102 as a fixed end.
[0076]
At this time, by applying an alternating current at a frequency similar to the resonance frequency uniquely determined by the shape and material of the movable plate 101 and the elastic member 102, the movable plate 101 vibrates with the maximum amplitude of the current value. Start.
[0077]
The vibration at this time is a two-dimensional vibration in which bending vibration and torsional vibration occur simultaneously. The resonance frequency of bending vibration and the resonance frequency of torsional vibration are uniquely determined by the shape and material of the movable plate 101 and the elastic member 102. It is determined.
[0078]
Therefore, when you want to vibrate in the resonance state in both the bending direction and the torsional direction, an alternating current that superimposes the current waveform that excites the resonance in the bending vibration mode and the current waveform that excites the resonance in the torsional vibration mode. May be applied to the drive coil 106.
[0079]
Therefore, the optical scanner according to the first embodiment has the following effects.
[0080]
The optical scanner in this embodiment can perform two-dimensional optical scanning.
[0081]
In this optical scanner, one drive coil 106 generates both bending vibration and torsional vibration.
[0082]
Therefore, if the optical scanner in this embodiment has the same shape, the bending angle during driving and the deflection angle in the torsional direction can be uniquely determined by the current value applied to the driving coil 106, and driving control is easy.
[0083]
In addition, since the optical scanner in the present embodiment uses polyimide, which is an organic film, as the elastic member 102, as described in the above-mentioned document “TECHNICAL DIGEST OF THE SENSOR SYMPOSIUM, 1995.pp17-20”. Brittle fracture is less likely to occur compared to the case of using simple silicon for the vibration member, and a large deflection angle can be obtained while maintaining the necessary minimum strength.
[0084]
Further, since electrical elements such as the drive coil 106, the wiring 108, and the contact pad 107 are formed inside the polyimide film, the electrical elements are hardly deteriorated by moisture, and the drive coil 106 is provided inside the polyimide film. The insulation between the wirings of the drive coil 106 is also stabilized.
[0085]
In addition, the driving coil 106 shown in the present embodiment has a shape that has been considered to obtain a large driving force while suppressing heat generated when a current is applied to the coil as much as possible.
[0086]
This driving force can be easily obtained by the following equation (1).
[0087]
F = ni ・ B (1)
Where F is the driving force, n is the number of turns of the coil, i is the amount of current flowing through the coil, and B is the average magnetic flux density on the wiring portion of the driving coil 106 formed close to the permanent magnet 104. Yes.
[0088]
In order to increase the driving force, it is effective to increase the amount of current flowing through the driving coil 106. However, if the amount of current is increased, heat is generated in the driving coil 106 and the electric power of the driving coil 106 is increased. As a result of the increased resistance, the conversion efficiency from current to driving force is degraded.
[0089]
Further, even if the number of turns of the driving coil 106 is increased in order to increase the driving force, the resistance of the driving coil 106 is increased, and the same problem as described above occurs.
[0090]
In order to increase the driving force, if the average magnetic flux density by the permanent magnet 104 is taken into consideration, the distance between the permanent magnet 104 and the driving coil 106 should be short.
[0091]
That is, it is desirable to reduce the line width and wiring interval of the drive coil 106, but if the line width of the entire wiring of the drive coil 106 is reduced, the problem of resistance occurs as described above.
[0092]
In order to suppress this as much as possible, in the present embodiment, as shown in FIG. 2 (a), only the wiring that contributes to the driving force is narrowed, and the distance between the wirings is narrowed. It is made to concentrate in the vicinity of the permanent magnet 104.
[0093]
Here, the reason why the wiring interval of the drive coil 106 that does not contribute to the drive force is increased is to improve the production yield of the drive coil 106.
[0094]
In this embodiment, the optical scanner can be integrally formed, and there is almost no assembly work, and the productivity as an ultra-compact optical scanner can be improved.
[0095]
In this embodiment, since the optical scanner uses semiconductor manufacturing technology, the dimensional accuracy of the miniaturized optical scanner is high, and the vibration of the optical scanner becomes unstable due to individual parts or assembly problems. There is no such thing.
[0096]
Of course, each configuration of this embodiment can be variously modified and changed.
[0097]
For example, as shown in FIG. 5, in order to obtain a torsional vibration more reliably with a large amplitude, a permanent magnet is provided in the vicinity of the side wall surface 122 located on the opposite side of the side wall of the movable plate 101 close to the portion to which the elastic member 102 is connected. 121 may be arranged.
[0098]
That is, the torsional vibration is generated because the elastic member 102 is connected to a position shifted from the center of the movable plate 101.
[0099]
In the case of torsion, the generated force is determined by the moment. In this configuration, the product of the length of the perpendicular from the portion where the generated force is generated to the rotation center axis and the generated force with the central axis of the elastic member 102 in the width direction as the rotation center. Is required.
[0100]
Since the permanent magnet 104 is arranged so that the driving force is distributed in the direction perpendicular to the rotation center axis, the driving force that generates torsional vibration cannot be obtained efficiently only by the permanent magnet 104.
[0101]
On the other hand, the permanent magnet 121 is disposed in the vicinity of the side wall surface 122 farthest from the rotation center axis, and the driving force generated in the wiring of the driving coil 106 passing through the vicinity of the permanent magnet 121 is far greater than the driving force generated by the permanent magnet 104. Efficient and big.
[0102]
In this configuration, as shown in FIG. 8A, the drive coil 106 has a wiring portion formed in the vicinity of the permanent magnet 104 and the permanent magnet 121 having a narrower wiring width and a smaller wiring interval than other wiring portions. It has become.
[0103]
As a result, the driving force can be obtained efficiently, the electric resistance of the driving coil is minimized, and the generation of heat when current is applied is minimized.
[0104]
<Second Embodiment>
6 to 10 show a second embodiment of the optical scanner according to the present invention and its modification.
[0105]
The optical scanner according to the second embodiment can perform two-dimensional light scanning. A perspective view of the optical scanner is shown in FIG. 6, and the drive coil used here is shown in FIG. 8B. Show.
[0106]
In the optical scanner according to the second embodiment, the configuration of the single drive coil 106 shown in the first embodiment is that the drive coils 206 and 207 are divided into two in the width direction of the optical scanner. And different.
[0107]
This optical scanner includes a movable plate 201, an elastic member 202, a support 203, a permanent magnet 204, and drive coils 206 and 207.
[0108]
The movable plate 201 is formed with a reflecting surface 205 for reflecting light, and the back surface of the movable plate 201 in FIG.
[0109]
As the material of the movable plate 201, it is desired that the reflection surface does not deform during vibration. Therefore, here, single crystal silicon which is a highly rigid material is used as the main material of the movable plate 201.
[0110]
In addition, silicon nitride, aluminum, and polyimide materials are used for the movable plate 201. Silicon nitride is used as a mask material when manufacturing an optical scanner, and aluminum is used for wiring of the drive coils 206 and 207 and the drive coil. In some cases, it is also used as a mirror material for the reflecting surface 205 as the contact pad 208 at the start and end points of 206 and 207.
[0111]
Polyimide is formed so that the drive coils 206 and 207 are sandwiched from above and below, so that the electrical elements including the insulation between the coil wires and the contact pads 208 are not exposed to the atmosphere.
[0112]
The elastic member 202 has a polyimide film extending from the movable plate 201 as a main material, and a wiring 209 extending from the contact pad 208 to the support 203 is formed therein.
[0113]
The wiring 209 is also made of aluminum.
[0114]
The support 203 is used as an adhesive portion for fixing the optical scanner to die cast or the like, and a bonding pad 210 for supplying electric power from the outside to the drive coils 206 and 207 through the wiring 209 is formed on the surface. ing.
[0115]
This support 203 uses single crystal silicon as a main material, and since single crystal silicon has high rigidity, it is convenient for fixing to a die cast or the like.
[0116]
In addition, as the material of the support 203, silicon nitride serving as a mask material for manufacturing an optical scanner, aluminum for forming the bonding pad 210 and the wiring 209, and the wiring 209 are sandwiched from above and below so that the wiring 209 is not exposed to the atmosphere. For example, a polyimide film is used.
[0117]
As the polyimide, polyimide extending from the movable plate 201 and the elastic member 202 is used.
[0118]
Further, the single crystal silicon of the support 203 and the single crystal silicon used in the movable plate 201 are formed from the same substrate.
[0119]
As shown in FIG. 8B, the drive coils 206 and 207 change the line width of the wiring and the distance between the wirings on each side.
[0120]
That is, the wiring of the drive coils 206 and 207 formed in the vicinity of the permanent magnet 204 in parallel with the width direction is narrower than the wiring formed in other places, and the interval between the wirings is also narrowed. ing.
[0121]
However, the thicknesses of the drive coils 206 and 207 are both uniform.
[0122]
With respect to the arrangement position of the permanent magnet 204, the configuration shown in the above-mentioned document “TECHNICAL DIGEST OF THE SENSOR SYMPOSIUM, 1995.pp17-20” is applied, and the magnetization direction is aligned with the plate thickness direction of the movable plate 201, The lower end of the permanent magnet 204 or the upper end of the permanent magnet 204 is arranged on an extension line of about 45 degrees above or below the driving coils 206 and 207 at the tip of the movable plate 201.
[0123]
The optical scanner according to the second embodiment can be manufactured by a method similar to the manufacturing method of the optical scanner shown in the first embodiment.
[0124]
Next, the operation of the optical scanner according to the second embodiment will be described.
[0125]
First, by applying an alternating current from the bonding pad 210, Lorentz force is generated by the interaction between the driving coils 206 and 207 that circulate around the tip of the movable plate 201 with the permanent magnet 204.
[0126]
The vector direction of the Lorentz force is determined by the positional relationship between the permanent magnet 204 and the drive coils 206 and 207. In this case, a force is generated in the thickness direction of the movable plate 201.
[0127]
If an alternating current having the same direction and magnitude is applied to the drive coils 206 and 207, the optical scanner starts bending vibration with the boundary between the support 203 and the elastic member 202 as a fixed end.
[0128]
However, when an alternating current is applied to the drive coils 206 and 207 in different directions and sizes, the optical scanner starts two-dimensional vibration in which torsional vibration is added in addition to bending vibration.
[0129]
Here, the vibration of the elastic member 202 in the plate thickness direction with the connection portion with the support 203 as a fixed end is called bending vibration, and the movable plate 201 rotates upward or downward with the central axis of the elastic member 202 as the rotation axis. The vibration that works in the direction to do is called torsional vibration.
[0130]
The amplitude of the movable plate 201 due to this bending vibration is the strength of the Lorentz force generated in the drive coils 206 and 207 and the length of the perpendicular from the point where the Lorentz force is generated to the side connected to the elastic member 202 of the support 203. It depends on the product.
[0131]
Further, in the case of the amplitude of the movable plate 201 due to torsional vibration, the strength of the Lorentz force generated in the drive coils 206 and 207 and the perpendicular line from the point where the Lorentz force is generated to the center axis with respect to the width direction of the elastic member 202 are shown. Determined by product with length.
[0132]
The Lorentz force is determined by the performance and size of the permanent magnet 204, the number of turns of the drive coils 206 and 207, the wiring length, the amount of current applied to the drive coils 206 and 207, and the distance from the permanent magnet 204 to the drive coils 206 and 207. .
[0133]
Here, the reason why the drive coils 206 and 207 circulate around the outermost periphery of the movable plate is to increase the amount of generated force as much as possible.
[0134]
Then, by fixing the support 203 to a die cast or the like (not shown) and applying a current to the drive coils 206 and 207, the movable plate 201 starts to vibrate with the boundary between the support 203 and the elastic member 202 as a fixed end. To do.
[0135]
At this time, by applying an alternating current at a frequency similar to the resonance frequency uniquely determined by the shape and material of the movable plate 201 and the elastic member 202, the movable plate 201 vibrates with the maximum amplitude in the current value. Start.
[0136]
Further, the vibration at this time is one-dimensional vibration only of bending vibration or two-dimensional vibration in which bending vibration and torsional vibration are generated simultaneously.
[0137]
Note that the resonance frequency of the bending vibration and the resonance frequency of the torsional vibration are uniquely determined by the shapes and materials of the movable plate 201 and the elastic member 202.
[0138]
In the case of having a plurality of drive coils as in the present embodiment, the vibration changes in a complex manner depending on the conditions of the applied current.
[0139]
For example, when only bending vibration is generated, an alternating current having a frequency similar to the resonance frequency of the bending mode may be applied to the drive coils 206 and 207.
[0140]
When only torsional vibration is generated, an alternating current having a frequency similar to the resonance frequency of the torsion mode may be applied to the drive coils 206 and 207.
[0141]
At this time, if the phase of the current applied to the drive coils 206 and 207 is shifted by 180 degrees, the movable plate 201 starts torsional mode vibration.
[0142]
If you want to vibrate in the resonance state for both the bending mode and the torsion mode, an alternating current that superimposes the current waveform that excites the resonance in the bending mode and the current waveform that excites the resonance in the torsion mode is used. What is necessary is just to apply to each drive coil 206,207.
[0143]
Therefore, the optical scanner according to the second embodiment has the following effects.
[0144]
The optical scanner according to the present embodiment can perform one-dimensional optical scanning with only bending vibrations, and can also perform two-dimensional optical scanning including torsional vibrations, and applies them to the drive coils 206 and 207. By controlling the direction and magnitude of the current, the amplitude of the bending vibration and the amplitude of the torsional vibration can be finely controlled, and the applied current is controlled even when the light scanning area is arbitrarily determined. It can respond by doing.
[0145]
In particular, when the aspect ratio of the scanning area changes, the optical scanner shown in the first embodiment cannot cope with it, but the optical scanner shown in this embodiment can cope with it.
[0146]
Further, in the optical scanner according to the second embodiment, since the polyimide which is an organic film is used as the elastic member 202, it is shown in the above-mentioned document “TECHNICAL DIGEST OF THE SENSOR SYMPOSIUM, 1995.pp17-20”. Compared to the case where silicon is used for the vibrating member, brittle fracture is less likely to occur, and a large deflection angle can be obtained while maintaining the necessary minimum strength.
[0147]
Further, since electrical elements such as the drive coils 206 and 207, the wiring 209, and the contact pad 208 are formed inside the polyimide film, the electrical elements are hardly deteriorated by moisture, and the drive coils 206 and 207 are placed inside the polyimide film. By providing this, the insulation between the wirings of the drive coils 206 and 207 is also stabilized.
[0148]
In addition, the drive coils 206 and 207 shown in this embodiment have a shape that has been considered for obtaining a large drive force while suppressing heat generated when a current is applied to the coil as much as possible.
[0149]
This driving force can be easily obtained by the equation (1) shown in the first embodiment.
[0150]
Here, for the sake of simplicity, assuming that the currents applied to the two drive coils 206 and 207 have the same direction and the same magnitude, from equation (1), in order to increase the drive force, the current amount is increased. It is also effective to do.
[0151]
However, in practice, if the amount of current is increased, heat is generated in the drive coils 206 and 207, and the electrical resistance of the drive coils 206 and 207 increases. As a result, the conversion efficiency from current to drive force deteriorates. End up.
[0152]
Further, even if the number of turns of the drive coils 206 and 207 is increased in order to increase the driving force, the resistance of the drive coils 206 and 207 increases, and the same problem as described above occurs.
[0153]
However, compared with the drive coil shown in the first embodiment, the drive coil of this configuration is divided into two parts, which is advantageous for the heat problem because the total wiring length of the coil is short.
[0154]
In order to increase the driving force, it is better that the distance between the permanent magnet and the driving coil is shorter in consideration of the average magnetic flux density.
[0155]
That is, it is desirable to narrow the line width and wiring interval of the drive coils 206 and 207, but if the line width of the entire wiring of the drive coils 206 and 207 is narrowed, the problem of resistance occurs as described above.
[0156]
In order to suppress this as much as possible, in the present embodiment, as shown in FIG. 8B, only the wiring that contributes to the driving force is narrowed in the line width, and the entire wiring is made permanent magnets by narrowing the wiring interval. It is made to concentrate in the vicinity of 204.
[0157]
Here, the reason why the wiring interval between the drive coils 206 and 207 that do not contribute to the drive force is increased is to improve the production yield of the drive coils 206 and 207.
[0158]
In the present embodiment, the optical scanner can be formed integrally, there is almost no assembly work, and the productivity of the ultra-compact optical scanner can be improved.
[0159]
In this embodiment, since semiconductor manufacturing technology is applied, the dimensional accuracy of the ultra-compact optical scanner is high, and the vibration of the optical scanner becomes unstable due to individual parts or assembly problems. There is nothing wrong.
[0160]
In addition, naturally each deformation | transformation of this embodiment can be variously modified and changed.
[0161]
As a first modification, permanent magnets 211 and 212 may be arranged at both ends in the width direction of the movable plate 201, respectively, as shown in FIG.
[0162]
The permanent magnets 211 and 212 can be efficiently converted into driving force if they are arranged with their magnetization directions aligned so as to form a magnetic field parallel to the width direction of the movable plate 201.
[0163]
In the optical scanner according to the first modified example, when it is desired to generate vibration only in the bending mode, the direction of the current applied to the drive coils 206 and 207 must be reversed. It is very different from the configuration.
[0164]
Further, the configuration in the second embodiment places importance on the efficiency in bending vibration, whereas the optical scanner according to this modification can be said to be a configuration in which the efficiency in torsional vibration is emphasized.
[0165]
This is because in the configuration shown in the second embodiment, the moment that affects torsional vibration is not uniformly distributed, but in the configuration of this modified example, the moment in the torsion mode is uniformly distributed. This is because the moment that affects the bending vibration is not uniformly distributed.
[0166]
In this configuration, as shown in FIG. 10A, the drive coils 206 and 207 are wiring portions formed in the vicinity of the permanent magnets 211 and 212 and have a narrower wiring width and a smaller wiring interval than other wiring portions. ing.
[0167]
As a result, the driving force can be obtained efficiently, the electric resistance of the driving coil is minimized, and the generation of heat when current is applied is minimized.
[0168]
As a second modification, as shown in FIG. 9, the drive coils 206 and 207 are configured with a configuration similar to that of the second embodiment so that individual control of bending vibration and torsional vibration can be performed more easily. The movable plate 201 may be divided into two in the width direction, and the permanent magnets 213 and 214 may be arranged in the respective drive coils 206 and 207 at positions where vibration modes shared by the coils are generated.
[0169]
Accordingly, the permanent magnet 213 corresponding to the drive coil 207 that generates bending vibration is disposed in the vicinity of the tip of the movable plate 201.
[0170]
The drive coil 206 is formed for the purpose of generating torsional vibration, and the permanent magnet 214 corresponding to the drive coil 206 is in the vicinity of the side wall surface located on the opposite side of the side wall of the movable plate 201 adjacent to the portion to which the elastic member 202 is connected. A permanent magnet 214 is disposed on the surface.
[0171]
In this configuration, since the drive coils 206 and 207 share the vibration direction, bending vibration occurs when a current is applied only to the drive coil 207, and incomplete when a current is applied only to the drive coil 206. However, torsional vibration occurs.
[0172]
In the second embodiment and the first modification example, when the bending vibration and the torsional vibration are generated at the same time, the current is applied in a waveform in which the bending vibration waveform and the torsional vibration waveform are superimposed on the two coils. However, in this modification, it is not necessary to superimpose, and it is only necessary to apply alternating currents for generating the respective modes to the respective drive coils 206 and 207.
[0173]
With this configuration, it is not necessary to superimpose waveforms, and the configuration of an electric circuit that forms a current waveform becomes easy.
[0174]
In this configuration, as shown in FIG. 10 (b), the wiring of the drive coils 206 and 207 has a wiring width narrower in the wiring portion formed in the vicinity of the permanent magnets 214 and 213 than the other wiring portions. The interval is also narrower.
[0175]
As a result, the driving force can be obtained efficiently, the electric resistance of the driving coil is minimized, and the generation of heat when current is applied is minimized.
[0176]
<Third Embodiment>
11 to 13 show a third embodiment of the optical scanner according to the present invention.
[0177]
The optical scanner according to this embodiment can perform two-dimensional light scanning and has a built-in detection coil for detecting a driving frequency. A sectional view of this optical scanner is shown in FIG. A top view of this optical scanner is shown in FIG.
[0178]
In this embodiment, an optical scanner incorporating a detection coil is described using the configuration shown in the first embodiment.
[0179]
This optical scanner is composed of a movable plate 301, an elastic member 302, a support 303, a permanent magnet 304, and a drive coil 305. The components constituting these are the same as those in the first embodiment. .
[0180]
The optical scanner also has a drive coil 305 formed on the movable plate 301 as an electrical element, a bonding pad 306 formed on the support 303, and a connection between the drive coil 305 and the bonding pad 306. And a detection coil 308 extending to the movable plate 301, the elastic member 302, and the support 303.
[0181]
The detection coil 308 and the drive coil 305 are insulated by the second polyimide layer 310.
[0182]
The detection coil 308 is sandwiched between the first polyimide layer 309 and the second polyimide layer 310, and the coil wirings are also insulated by the polyimide.
[0183]
Contact pads 311 are formed at the start and end points of the drive coil 305.
[0184]
Only the portion of the contact pad 311 is removed from the third polyimide layer 312 that provides insulation between the wirings of the drive coil 305, and the contact pad 311 is electrically connected to the wiring 307.
[0185]
The wiring 307 is also shielded from the atmosphere by the fourth polyimide layer 313.
[0186]
The wiring 303 and the bonding pad 306 are electrically connected by the support 303.
[0187]
The support 303 is formed with bonding pads 314 that are electrically connected to the start and end points of the detection coil 308.
[0188]
Next, the operation of this embodiment will be described.
[0189]
First, by applying an alternating current from the bonding pad 306, a Lorentz force is generated in the drive coil 305 that circulates at the tip of the movable plate 301 by the interaction with the permanent magnet 304.
[0190]
The vector direction of the Lorentz force is determined by the positional relationship between the permanent magnet 304 and the drive coil 305. In this case, the Lorentz force is generated in the thickness direction of the movable plate 301.
[0191]
In this optical scanner, since the connecting portion between the elastic member 302 and the movable plate 301 is deviated from the center in the width direction of the movable plate 301, it is not possible to create only bending vibration, and a structure in which bending vibration and torsional vibration occur simultaneously. It has become.
[0192]
Here, the vibration of the elastic member 302 in the thickness direction with the connecting portion with the support 303 as a fixed end is called bending vibration, and the movable plate 301 rotates upward or downward with the central axis of the elastic member 302 as the rotation axis. The vibration that works in the direction to do is called torsional vibration.
[0193]
When the movable plate 301 starts to vibrate, an induced electromotive voltage V as shown in Expression (2) is generated in the detection coil 308.
[0194]
V = B · v · l (2)
Here, B is the average magnetic flux density on the coil wiring formed in the vicinity of the permanent magnet 304, v is the vibration speed of the movable plate 301, and l is the wiring length of the detection coil 308 that generates the induced electromotive voltage. ing.
[0195]
The voltage waveform obtained from the detection coil 308 has the same waveform as the vibration waveform of the movable plate 301, and is the same waveform as the current waveform applied to the drive coil 305, but is output with a phase shift.
[0196]
Therefore, the optical scanner according to the third embodiment has the following effects.
[0197]
By incorporating the detection coil 308 integrally with the optical scanner, the optical scanner including the detection coil 308 can be integrally formed, and there is almost no assembly work, and the productivity of the ultra-small optical scanner can be improved. it can.
[0198]
Further, since the semiconductor manufacturing technology is applied, the dimensional accuracy of the ultra-miniaturized optical scanner is high, and the vibration of the optical scanner does not become unstable due to individual parts or assembly problems.
[0199]
Further, even if heat is generated by the drive coil 305, the detection signal from the detection coil 308 representing the vibration state is not affected at all, and a signal with higher accuracy than the detection system using a strain gauge or the like can be detected. it can.
[0200]
This detection signal is not only used for evaluating the vibration state of the movable plate 301, but also using this detection signal as shown in FIG. 13, self-excited oscillation that allows the optical scanner to always vibrate in a resonance state. The circuit 315 can also be configured.
[0201]
By causing this optical scanner to self-oscillate, stable resonance driving can always be performed without being affected by the temperature environment and the change of the elastic member 302 over time.
[0202]
In the embodiments as described above, the present invention includes the following inventions.
[0203]
(1) A support for fixing to an arbitrary member, a movable plate in which at least one surface is a reflection surface that reflects light, and the support while giving the movable plate at least two degrees of freedom. And an elastic member for connecting the movable plate, a drive coil having at least two sides formed on the movable plate, and a permanent magnet disposed in the vicinity of the movable plate with a space therebetween, By applying an alternating current to the optical scanner, the movable plate performs bending and torsional vibration with the connecting portion between the elastic member and the support as a fixed end, and the elastic member has an electric element inside. An optical scanner comprising: an insulating elastic film that reaches the movable plate and the support.
[0204]
(Corresponding Embodiment of the Invention)
The embodiment relating to the invention of (1) corresponds to the first embodiment.
[0205]
As shown in the first embodiment, the drive coil in the invention of (1) is a coil that generates a force to vibrate the movable plate by interaction with a permanent magnet when an alternating current is applied. In this embodiment, a planar coil is used.
[0206]
The electric element in the invention of (1) is a generic term for a drive coil, a detection coil, an electric wiring, an electrode pad, and the like.
[0207]
(Function, effect)
The optical scanner according to the invention of (1) is a two-dimensional optical scanner that can be driven two-dimensionally despite only one drive coil, and has a simple configuration and is easy to manufacture.
[0208]
In addition, the optical scanner according to the invention of (1) uses an insulating elastic film for the leaf spring portion, so that brittle fracture is less likely to occur than when silicon is used for the vibration member, and the minimum necessary strength. A large deflection angle can be obtained while maintaining
[0209]
Further, in the optical scanner according to the invention of (1), since the electric elements are formed inside the insulating elastic film, there is almost no deterioration due to moisture of the electric elements, and the elastic film is used for insulation between the electric elements. Can be used.
[0210]
(2) A support for fixing to an arbitrary member, a movable plate in which at least one surface reflects light, and the support while allowing the movable plate to have two or more degrees of freedom. And an elastic member for connecting the movable plate, a plurality of drive coils having at least one side formed on the movable plate, and a permanent magnet arranged at intervals in the vicinity of the movable plate, By applying an alternating current to the coil, the movable plate performs bending and torsional vibration with the connecting portion between the elastic member and the support as a fixed end, and the elastic member has an electric element inside. And an insulating elastic film that reaches the movable plate and the support.
[0211]
(Corresponding Embodiment of the Invention)
The embodiment relating to the invention of (2) corresponds to the second embodiment.
[0212]
As shown in the second embodiment, the drive coil in the invention of (2) is a coil that generates a force to vibrate the movable plate by interaction with a permanent magnet when an alternating current is applied. In the embodiment, a planar coil is used.
[0213]
The electric element in the invention of (2) is a generic term for a drive coil, a detection coil, an electric wiring, an electrode pad, and the like.
[0214]
(Function, effect)
The optical scanner according to the invention of (2) can control the vibration of the movable plate in a more complicated manner than the optical scanner according to the invention of (1) by using a plurality of drive coils.
[0215]
The scanner according to the invention of (2) is capable of one-dimensional drive as well as two-dimensional drive, and the amplitude in each mode of two-dimensional drive is individually controlled by adjusting the amount of current applied to the drive coil. be able to.
[0216]
In addition, the scanner according to the invention of (2) uses an insulating elastic film for the leaf spring portion, so that brittle breakage is less likely to occur than when silicon is used for the swinging member, and the minimum necessary strength. A large deflection angle can be obtained while maintaining
[0217]
In the scanner according to the invention (2), since the electric elements are formed inside the insulating elastic film, the electric elements are hardly deteriorated by moisture, and the elastic film is used for insulation between the electric elements. Can be used.
[0218]
(3) The permanent magnet has two or more permanent magnets, at least one permanent magnet is disposed in the vicinity of the tip of the movable plate with respect to the support, and at least another permanent magnet is the movable plate. The optical scanner according to (1), which is disposed in the vicinity of the side surface.
[0219]
(Corresponding Embodiment of the Invention)
The embodiment relating to the invention of (3) corresponds to a modification of the first embodiment.
[0220]
(Function, effect)
In the optical scanner according to the invention of (3), by arranging the permanent magnet in the vicinity of the side wall of the movable plate, the deflection angle with respect to the torsional direction can be made as compared with the case where the permanent magnet is arranged only in the vicinity of the tip of the movable plate. It can be taken big.
[0221]
(4) The optical scanner according to (2), wherein the permanent magnet includes two or more permanent magnets, and at least two permanent magnets are disposed in the vicinity of both side walls of the movable plate. .
[0222]
(Corresponding Embodiment of the Invention)
The embodiment relating to the invention of (4) corresponds to the first modification of the second embodiment.
[0223]
(Function, effect)
In the optical scanner according to the invention of (4), permanent magnets are arranged in the vicinity of both side walls of the movable plate, respectively, so that a single permanent magnet is arranged in the vicinity of the tip of the movable plate. A large deflection angle can be obtained.
[0224]
However, since the optical scanner according to the invention of (4) has a small deflection angle with respect to the bending direction, it is an effective configuration when designing based on the direction angle in the torsional direction.
[0225]
(5) The permanent magnet includes two or more permanent magnets, and at least one permanent magnet is disposed in the vicinity of the tip of the movable plate with respect to the support, and one drive coil of the plurality of drive coils. A permanent magnet that affects only one of the plurality of drive coils, and at least another permanent magnet is disposed near the side surface of the movable plate and affects only the other one of the plurality of drive coils. The optical scanner according to (2), wherein the permanent magnets are arranged so as to affect different drive coils.
[0226]
(Corresponding Embodiment of the Invention)
The embodiment relating to the invention of (5) corresponds to the second modification of the second embodiment.
[0227]
(Function, effect)
In the optical scanner according to the invention of (5), each permanent magnet is arranged so as to affect only one drive coil, and therefore, when an alternating current is applied only to one drive coil, The generated vibration mode can be limited to almost one.
[0228]
Further, if the configuration of the optical scanner according to the invention of (5) is used, it is not necessary to apply a current to different drive coils in a waveform obtained by superimposing a bending vibration waveform and a torsional vibration waveform. What is necessary is just to apply the alternating current which generates each mode to a drive coil.
[0229]
Therefore, in the optical scanner according to the invention of (5), the configuration of the electric circuit that forms the current waveform becomes easy.
[0230]
(6) The optical scanner according to (1), (2), (3), (4), or (5), wherein the insulating elastic film is made of an organic film.
[0231]
(Corresponding Embodiment of the Invention)
The embodiment relating to the invention of (6) corresponds to the first, second and third embodiments.
[0232]
(Function, effect)
The optical scanner according to the invention of (6) is less susceptible to brittle fracture by using an organic film for the leaf spring portion than when silicon or the like is used for the vibration member, and is large while maintaining the necessary minimum strength. A deflection angle can be obtained.
[0233]
(7) (1), (2), (3), (4), characterized in that the drive coil has a minimum width of the wiring of the driving coil and a space between the wirings in the vicinity of the permanent magnet. (5) The optical scanner according to (6).
[0234]
(Corresponding Embodiment of the Invention)
The embodiment relating to the invention of (7) corresponds to the first and second embodiments.
[0235]
(Function and effect)
The optical scanner according to the invention of (7) makes the coil wiring near the permanent magnet a permanent magnet by narrowing the interval of the coil wiring that contributes to the generation of the force formed in the vicinity of the permanent magnet and narrowing the width of the wiring. It is possible to make it closer, and it is possible to obtain a larger generating force than a normal coil.
[0236]
In the optical scanner according to the invention of (7), the width of the coil wiring that does not contribute to generation of force is sufficiently widened, and the problem of heat generated by widening the interval of the coil wiring is minimized. be able to.
[0237]
Further, the optical scanner according to the invention of (7) can improve the production yield by widening the space between the coil wirings in the portion that does not contribute to the generation of force.
[0238]
(8) (1), (2), (3), (4) characterized in that at least one side is integrally formed in the movable plate and has a detection coil for detecting the vibration frequency of the movable plate. ), (5) and (6).
[0239]
(Corresponding Embodiment of the Invention)
The embodiment relating to the invention of (8) corresponds to the third embodiment.
[0240]
The detection coil in the invention of (8) indicates a coil that generates an induced electromotive force by interaction with a permanent magnet as shown in the third embodiment. In the third embodiment, the detection coil is supported by a movable plate, an elastic member, and a support. A planar coil extending to the body is used.
[0241]
(Function and effect)
In the optical scanner according to the invention of (8), even if the detection coil generates heat by the drive coil, there is no influence on the detected signal, and the signal detection can be performed with higher accuracy than the detection system using a strain gauge or the like. It is.
[0242]
In the optical scanner according to the invention of (8), not only the vibration state of the movable plate is evaluated using the detection signal from the detection coil, but also the optical scanner can be vibrated in the resonance state at all times using this detection signal. It can also be configured as a self-excited oscillation circuit.
[0243]
In other words, in the optical scanner according to the invention of (8), the optical scanner can be oscillated by self-excited oscillation, so that stable resonance driving can always be performed without being influenced by the environmental temperature and the change with time of the elastic member.
[0244]
The first and second prior arts described above do not describe the viewpoints of durability and protection from the atmosphere of electrical elements such as optical scanner wiring that vibrates with a large deflection angle.
[0245]
The inventions (1) to (5) described above pay attention to such points, and provide an optical scanner having an electrical element exhibiting high durability in an optical scanner that vibrates with a large deflection angle. It is what.
[0246]
Further, the above-described first and second prior arts do not describe the viewpoint of increasing the deflection angle of the optical scanner.
[0247]
The above-described invention (6) pays attention to this point, and by using an elastic film, specifically an organic film, as the leaf spring part, the rigidity of the spring part is lowered, and the generated force amount is reduced due to downsizing. Nevertheless, it is an object of the present invention to provide an optical scanner capable of obtaining a large deflection angle.
[0248]
Further, the second prior art described above does not describe the viewpoint of minimizing the influence of heat generated when a current is passed through the coil.
[0249]
The above-described invention of (7) pays attention to this point, and an object thereof is to provide an optical scanner having a coil shape that minimizes heat generated in the coil.
[0250]
In the first and second prior arts described above, a device that is integrally formed with the optical scanner and monitors the vibration state performs accurate detection regardless of environmental changes or optical scanner changes over time. The viewpoint is not described.
[0251]
The above-described invention of (8) pays attention to this point, and an object of the invention is to provide an optical scanner in which a device for monitoring a vibration state resistant to environmental changes is integrally formed.
[0252]
【The invention's effect】
Therefore, as described in detail above, according to the present invention, it is possible to provide an optical scanner having an electrical element exhibiting high durability in an optical scanner that vibrates with a large deflection angle.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a configuration of an optical scanner according to a first embodiment of the invention.
FIG. 2 is a plan view showing a configuration of a drive coil and a cross-sectional view showing a configuration of an optical scanner in the first embodiment.
FIG. 3 is a cross-sectional view showing a manufacturing process of the optical scanner according to the first embodiment.
FIG. 4 is a cross-sectional view showing a manufacturing process of the optical scanner according to the first embodiment.
FIG. 5 is a perspective view showing a configuration of a modification of the optical scanner according to the first embodiment.
FIG. 6 is a perspective view showing a configuration of an optical scanner according to a second embodiment of the invention.
FIG. 7 is a perspective view showing a configuration of a first modification of the optical scanner according to the second embodiment.
FIG. 8 is a plan view showing a configuration of a drive coil in a modification of the first embodiment and in the second embodiment.
FIG. 9 is a perspective view showing a configuration of a second modification of the optical scanner according to the second embodiment.
FIG. 10 is a plan view showing a configuration of a drive coil in a first modification and a second modification of the second embodiment.
FIG. 11 is a sectional view showing a configuration of an optical scanner according to a third embodiment of the invention.
FIG. 12 is a plan view showing a configuration of an optical scanner according to a third embodiment.
FIG. 13 is a diagram illustrating an application example of the optical scanner according to the third embodiment.
FIG. 14 is a diagram showing a configuration of a first conventional technique.
FIG. 15 is a diagram showing a configuration of a second prior art.
[Explanation of symbols]
101, 201, 301 ... movable plate,
102, 202, 302 ... elastic member,
103, 203, 303 ... support,
104, 204, 211, 212, 213, 214, 304 ... permanent magnets,
105, 205, ... reflective surface,
106, 206, 207, 305... Drive coil,
107, 208, 311 ... contact pads,
108, 209, 307 ... wiring,
109, 210, 306, 314 ... bonding pads,
110 ... silicon substrate,
111 ... Silicon nitride film,
112, 309 ... first polyimide layer,
113, 310 ... second polyimide layer,
313 ... fourth polyimide layer,
114, 312 ... third polyimide layer,
313 ... fourth polyimide layer,
308 ... detection coil,
315: Self-excited oscillation circuit.

Claims (5)

A support for fixing to an arbitrary member;
A movable plate, at least one of which is a reflecting surface that reflects light;
An elastic member that connects the support and the movable plate so as to deviate from the center with respect to the width direction of the movable plate;
A drive coil formed on the movable plate;
A permanent magnet disposed at a distance in the vicinity of the tip portion of the movable plate,
By applying an alternating current to the drive coil, the movable plate performs bending and torsional vibration with the connecting portion between the elastic member and the support as a fixed end,
The optical scanner has an electric element inside and is an insulating elastic film that reaches the movable plate and the support. A support for fixing to an arbitrary member;
A movable plate, at least one of which is a reflecting surface that reflects light;
An elastic member connecting the support and the movable plate;
A plurality of drive coils formed along the width direction of the movable plate on the movable plate;
A permanent magnet disposed in the vicinity of the movable plate at an interval, and by applying an alternating current to the plurality of drive coils, the movable plate fixes the connecting portion between the elastic member and the support body. An optical scanner that performs bending and torsional vibration at the end,
An optical scanner characterized in that the elastic member is an insulating organic elastic film having an electric element inside and reaching the movable plate and the support. A support for fixing to an arbitrary member;
A movable plate, at least one of which is a reflecting surface that reflects light;
An elastic member connecting the support and the movable plate;
A drive coil formed on the movable plate;
Comprising a permanent magnet disposed at a distance in the vicinity of the front end portion of the movable plate and in the vicinity of the side wall portion;
By applying an alternating current to the drive coil, the movable plate performs bending and torsional vibration with the connecting portion between the elastic member and the support as a fixed end,
An optical scanner characterized in that the elastic member is an insulating organic elastic film having an electric element inside and reaching the movable plate and the support.   4. The drive coil according to claim 1, wherein the drive coil is configured such that a wiring width and a space between the wirings are minimized at a portion facing the permanent magnet. 5. Optical scanner.   The optical scanner according to claim 1, wherein a detection coil for detecting a vibration frequency when the movable plate vibrates is formed on the movable plate.

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