JP2010032796A - Optical scanning type projector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical scanning type projector whose assembly workability is improved and which is easily made compact. <P>SOLUTION: The optical scanning type projector includes: light source parts (2R, 2G, 2B) which generate a plurality of different colors of light modulated on the basis of an image signal; color synthesizing parts (5, 6, 8) which synthesize the plurality of colors of light from the light source parts onto one and the same axis; a beam scanning part 17 which deflects the synthesized light synthesized with the color synthesizing parts in two dimensional direction according to the image signal; a free curved face prism 18 which has a plurality of optical faces having non-rotational-symmetry shapes, and projects the synthesized light deflected with the beam scanning part while enlarging at least deflection angle to display an image; and a base member 51 which holds at least the beam scanning part and the free curved face prism, wherein the beam scanning part 17 is mounted on a supporting member 91, the supporting member 91 is fixed on the base member 51, the free curved face prism 18 is fixed on the base member 51 via flange-shaped members (18g, 18h) formed on non-optical faces, and the beam scanning part 17 and the free curved face prism 18 are positioned. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an optical scanning projector that displays an image by two-dimensionally scanning a light beam and projecting it onto a screen.

  As this type of optical scanning projector, for example, red (R) light, green (G) light, and blue (B) laser light modulated based on an image signal are collimated by collimator lenses. Thereafter, there is known a technique in which an image is displayed by two-dimensional scanning by an optical scanning unit and projected on a screen (for example, see Patent Document 1). Further, as another optical scanning projector, each of the R light, G light, and B light modulated based on the image signal is condensed by a condenser lens, and two-dimensional scanning is performed by an optical scanning means. Then, what is projected on a screen to display an image is known (for example, see Patent Document 2).

JP 2006-184663 A JP 2006-186243

  In the optical scanning projectors disclosed in Patent Documents 1 and 2 described above, the entire apparatus is reduced in size so that it can be easily carried by reducing the size of the light source and the optical system.

  However, in the above optical scanning projector, the modulated R, G, B light is simply two-dimensionally scanned by the optical scanning means and projected onto the screen to display an image. Here, in general, when the optical system is miniaturized, the optical scanning means is also miniaturized, and accordingly, the scanning angle tends to be small. As described above, when the scanning angle of the light scanning unit is reduced, when a large-size image is displayed, the display distance from the projector main body to the display screen becomes long. Depending on the use environment, the image can be displayed at a desired angle of view. It may not be displayed. Further, since the display distance to the screen becomes long, the distance from the screen to the observer also becomes long, and there is a concern that the brightness of the image observed by the observer is lowered.

  In order to solve such a problem, the inventors of the present invention synthesized the modulated R, G, B light coaxially, deflected the synthesized light in a two-dimensional direction by the beam scanning unit, We are developing an optical scanning projector that projects the deflection angle with a free-form surface prism. According to this optical scanning projector, an image with a wide angle of view can be displayed even though it is small, so that it can be used in a narrow space without being influenced by the use environment.

  However, according to an experimental study by the present inventors, in the above optical scanning projector, the combined light deflected in the two-dimensional direction by the beam scanning unit is incident on the free-form surface prism, and the deflection angle is enlarged and projected. Therefore, it is necessary to position both with high accuracy and attach them to the base member. For this reason, in particular, in the case of a small configuration, if the beam scanning unit and the free-form surface prism having a complicated shape are directly attached to the base member, it takes time to attach and the assemblability may deteriorate. Concerned.

  Accordingly, an object of the present invention made in view of such a point is to provide an optical scanning projector that can improve assemblability and can be easily downsized.

The invention of the optical scanning projector according to claim 1 that achieves the above object comprises a light source unit that generates a plurality of different color lights modulated based on an image signal, and a plurality of color lights from the light source unit combined coaxially. A color synthesizing unit, a beam scanning unit for deflecting the synthesized light synthesized by the color synthesizing unit in a two-dimensional direction according to the image signal, and a plurality of optical surfaces having a non-rotation target shape, A free-form surface prism for projecting at least a deflection angle and projecting the combined light deflected by the scanning unit to display an image; and a base member holding at least the beam scanning unit and the free-form surface prism; Comprising
The beam scanning unit is attached to a support member, the support member is fixed to the base member, and the free-form curved prism is fixed to the base member via a hook-shaped member formed on a non-optical surface, The beam scanning unit and the free-form surface prism are positioned so as to be positioned.

The invention according to claim 2 is the optical scanning projector according to claim 1,
The beam scanning unit has a two-dimensional scanning mirror,
The support member is provided with a reflection mirror that reflects the combined light combined by the color combining unit and makes it incident on the two-dimensional scanning mirror.
It is characterized by this.

The invention according to claim 3 is the optical scanning projector according to claim 1,
The beam scanning unit includes two one-dimensional scanning mirrors that deflect the combined light combined by the color combining unit in directions orthogonal to each other.
It is characterized by this.

  According to the present invention, in contrast to the beam scanning unit and free-form surface prism that require high-precision positioning, the free-form surface prism having a complicated shape is attached to the base member via the hook-shaped member formed on the non-optical surface. Since the mounting and beam scanning unit are mounted on the support member and the support member is mounted on the base member, the beam scanning unit and the free-form surface prism can be positioned and mounted easily and with high accuracy even in a small configuration. It becomes possible. Therefore, the assemblability can be improved and the size can be easily reduced.

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

(First embodiment)
FIG. 1 is a diagram showing a schematic configuration of an optical system of the optical scanning projector according to the first embodiment of the present invention. The optical scanning projector 1 includes a laser light source 2R that generates R light, a laser light source 2G that generates G light, and a laser light source 2B that generates B light. These laser light sources 2R, 2G, and 2B emit the R light, G light, and B light in the same direction (upward on the paper surface in FIG. 1), from left to right in FIG. The laser light source 2R and the laser light source 2B are arranged in this order.

  The laser light source 2R is constituted by, for example, a semiconductor laser, and emits R-modulated light by driving the semiconductor laser based on an R signal of an image signal to be displayed. The R-modulated light that is diffused and emitted from the laser light source 2R is converted into parallel light by the collimator lens 3R, passes through the stop 4R, and is substantially perpendicular to the total reflection prism 5 having a dielectric multilayer film (in FIG. Reflected in the right direction) and incident on the dichroic prism 6.

  Similarly, the laser light source 2B is composed of, for example, a semiconductor laser, and emits B-modulated light by driving the semiconductor laser based on the B signal of the image signal to be displayed. The B-modulated light that is diffused and emitted from the laser light source 2B is collimated by the collimator lens 3B, and then enters the dichroic prism 6 through the stop 4B.

  The dichroic prism 6 transmits the incident R-modulated light and reflects the B-modulated light at a substantially right angle (in the right direction on the paper in FIG. 1), thereby combining the R-modulated light and the B-modulated light to generate the RB synthesized light. And the RB combined light is incident on the beam shaping unit 7.

  The beam shaping unit 7 includes two wedge prisms 7a and 7b, and the beam cross-sectional shape of the incident RB combined light is circular with a uniform light amount distribution and a light beam diameter of approximately 1 mm in the present embodiment. Shape it. The RB synthesized light beam shaped by the beam shaping unit 7 is incident on the dichroic prism 8.

  On the other hand, the laser light source 2G includes, for example, a semiconductor laser 11a that generates infrared light, a nonlinear optical crystal that generates G light of the second harmonic when excited by the laser light from the semiconductor laser 11a, and the generated G A DPSS laser having an SHG (Second Harmonic Generation) optical system 11b including an optical system for emitting light as parallel light having a light beam diameter of approximately 70 μm, and the semiconductor laser 11a is a G signal of an image signal to be displayed. By driving based on the above, the SHG optical system 11b emits parallel G-modulated light having a circular shape with a light beam diameter of approximately 70 μm and a substantially uniform light amount distribution. As such a DPSS laser, for example, a green laser manufactured by Melles Griot is known.

  The G-modulated light emitted from the laser light source 2G is reflected by the reflecting mirror 12 at a substantially right angle (in the right direction in FIG. 1) so as to be parallel to the optical path of the red / blue synthesized light by the dichroic prism 6. Then, the light is reflected by the reflecting mirror 13 in a direction almost opposite to the emission direction from the laser light source 2 </ b> G (downward in FIG. 1) and is incident on the dichroic prism 8.

  In the present embodiment, the beam expander 15 is disposed in the optical path of the G-modulated light between the reflection mirror 12 and the reflection mirror 13. The beam expander 15 is composed of, for example, two single convex lenses 15a and 15b. The incident-side single convex lens 15a has a focal length f1 of, for example, f1 = 2 mm, and the outgoing-side single convex lens 15b has a focal length of f2 of, for example, f2 = 30 mm. Is enlarged by about 30/2 from about 70 μm to about 1 mm.

  The dichroic prism 8 transmits the incident RB combined light and reflects the G-modulated light at a substantially right angle (right direction in FIG. 1), thereby combining the RB combined light and the G-modulated light to combine RGB. Light is generated, and the combined light is reflected by the reflection mirror 16 and is incident on the beam scanning unit 17.

  The beam scanning unit 17 includes, for example, a two-dimensional scanning mirror 17a that is rotated in a two-dimensional direction by electromagnetic driving means, and deflects the combined light from the reflection mirror 16 in the two-dimensional direction by the two-dimensional scanning mirror 17a. To be configured. The combined light deflected by the two-dimensional scanning mirror 17a has its deflection angle enlarged by the free-form surface prism 18 and is emitted through an emission opening 19 provided in the projector housing, thereby displaying a display unit 20 such as a screen or a wall. The light is projected onto and the image is displayed.

  Therefore, in the present embodiment, the laser light sources 2R, 2G, and 2B constitute a light source unit, and the total reflection prism 5, the dichroic prism 6, the reflection mirror 12, the reflection mirror 13, and the dichroic prism 8 serve as a color composition unit. It is composed.

  Next, the free-form surface prism 18 will be described. In the present embodiment, the free-form surface prism 18 includes a first optical surface 18a to a fourth optical surface 18d made of a free-form surface having a non-rotation target shape. The first optical surface 18a is an optical surface having a transmission region having a transmission effect with an antireflection coating and an internal reflection region having an internal reflection function with a reflection coating, and the second optical surface 18b and the third optical surface. Reference numeral 18c denotes an optical surface having an internal reflection function, each of which is provided with a reflective coating, and the fourth optical surface 18d is an optical surface having a transmission function, which is provided with an antireflection coating.

  The combined light deflected by the beam scanning unit 17 is incident on the free-form surface prism 18 from the transmission region of the first optical surface 18a into the prism, and the internal reflection of the second optical surface 18b and the first optical surface 18a. The combined light reflected by the region and the third optical surface 18c is sequentially reflected from the fourth optical surface 18d, and is emitted to the outside through the emission opening 19. Thereby, in the free-form surface prism 18, the combined light incident on the first optical surface 18a from the beam scanning unit 17 is projected from the fourth optical surface 18d in a direction intersecting with the incident direction by expanding the deflection angle. At the same time, the aberration of the spot of the synthesized light and the distortion of the display image are corrected. In the present embodiment, in the vertical direction of the image to be displayed, the angle formed by the incident optical axis of the synthesized light on the first optical surface 18a and the outgoing optical axis of the synthesized light from the fourth optical surface 18d is The free-form surface prism 18 is configured so that the combined light deflection range by the beam scanning unit 17 is less than 90 ° at the maximum, for example, 70 ° at the maximum.

  In the present embodiment, the free-form surface prism 18 is provided with an imaging function, and after the combined light is reflected by the second optical surface 18b, it reaches the internal reflection region of the first optical surface 18a. An image is formed to form an intermediate image of the combined light, and further, a beam waist is formed at a position separated from the fourth optical surface 18d by a predetermined distance, for example, at a position 60 cm from the exit opening 19, and more than a predetermined distance. In this case, when the total deflection angle of the image displayed by the combined light is 2θ, the beam diameter of the combined light is configured to increase in proportion to tanθ.

  Here, the free-form surface prism 18 used in the present embodiment will be described in more detail. In FIG. 1, the axial principal ray is defined as a ray that passes through the center of the entrance pupil of the optical system including the free-form surface prism 18 and reaches the center of the display unit 20. Further, the center of the entrance pupil is the origin, the direction along the axial principal ray is the Z-axis positive direction, the plane including the Z-axis and the image plane center in the display unit 20 is the YZ plane, and passes through the origin. A direction orthogonal to the YZ plane and extending from the front side of the paper to the back side is defined as the X axis positive direction, and the X axis, the Z axis, and the axis constituting the right hand orthogonal coordinate system are defined as the Y axis.

  The first optical surface 18a to the fourth optical surface 18d are decentered in the YZ plane, and the only symmetrical surface having a non-rotationally symmetric shape is the YZ plane.

  For the decentered surface, the amount of decentering of the surface top position of the surface from the origin of the optical system (X-axis direction, Y-axis direction, and Z-axis direction are X, Y, and Z, respectively) and the center axis ( The tilt angles (referred to as α, β, and γ (°), respectively) about the X axis, the Y axis, and the Z axis of the following (1) equation (1) are given. In this case, positive α and β mean counterclockwise rotation with respect to the positive direction of each axis, and positive γ means clockwise rotation with respect to the positive direction of the Z axis. Note that the α, β, and γ rotations of the central axis of the surface are performed by first rotating the central axis of the surface and its XYZ Cartesian coordinate system by α counterclockwise around the X axis, and then rotating it. The center axis of the surface is rotated β counterclockwise around the Y axis of the new coordinate system, and the coordinate system rotated once is also rotated β counterclockwise around the Y axis and then rotated twice The center axis of the surface is rotated γ clockwise around the Z axis of the new coordinate system.

  The free-form surface is defined by the following formula (1), and the Z-axis defined by the formula (1) is the axis of the free-form surface.

In the above equation (1), the first term is a spherical term, and the second term is a free-form surface term. In the spherical term, R is the radius of curvature of the apex, k is the conic constant, and r is (X ² + Y ² ) ^1/2 . Further, the free-form surface term is developed as shown in the following equation (2). However, C _j (j is an integer of 1 or more) is a coefficient.

In general, a free-form surface does not have a symmetric surface in both the XZ plane and the YZ plane, but by setting all odd-order terms of X to 0, a symmetric plane parallel to the YZ plane can be obtained. Only one free-form surface exists. For example, in the above formula (2), C ₂ , C ₅ , C ₇ , C ₉ , C ₁₂ , C ₁₄ , C ₁₆ , C ₁₈ , C ₂₀ , C ₂₃ , C ₂₅ , C ₂₇ , C ₂₉ , C ₃₁ , C ₃₃ , C ₃₅ ,...

Further, by setting all odd-numbered terms of Y to 0, a free-form surface having only one symmetry plane parallel to the XZ plane is obtained. For example, in the above formula (2), C ₃ , C ₅ , C ₈ , C ₁₀ , C ₁₂ , C ₁₄ , C ₁₇ , C ₁₉ , C ₂₁ , C ₂₃ , C ₂₅ , C ₂₇ , C ₃₀ , C ₃₂ , C ₃₄ , C ₃₆ ,...

  Further, if any one of the above-mentioned symmetric plane directions is a symmetric plane, the eccentric direction of the corresponding direction, for example, the symmetric plane parallel to the YZ plane, the eccentric direction of the optical system is the Y-axis direction, and X- By making the decentering direction of the optical system in the X-axis direction with respect to the symmetrical plane parallel to the Z plane, it is possible to improve the manufacturability at the same time while effectively correcting the rotationally asymmetric aberration caused by the decentering.

In the present embodiment, the free-form surface prism 18 is formed of a medium having an Abbe number of 56.2 and a refractive index of 1.5254 with respect to the d-line (wavelength: 587.56 nm). The first optical surface 18a has free-form surface terms as follows: C ₄ : −1.4999 × 10 ⁻² , C ₆ : 3.7510 × 10 ⁻² , C ₈ : −7.3349 × 10 ⁻³ , C10 : 3.1467 × 10 ⁻³ , C11: 3.0604 × 10 ⁻⁴ , C ₁₃ : −2.9467 × 10 ⁻⁴ , C ₁₅ : 5.5794 × 10 ⁻⁵ , and the amount of eccentricity is X: 0.00, Y: 0.89, Z: 4.02, and the inclination angles are α: 25.73, β: 0.00, and γ: 0.00.

The second optical surface 18b has a free-form surface term of C ₄ : −2.5781 × 10 ⁻² , C ₆ : −2.7720 × 10 ⁻² , C ₈ : −1.1244 × 10 ⁻³ , C ₁₀ : 2.8792 × 10 ⁻⁴ , the eccentricity is X: 0.00, Y: 2.46, Z: 12.17, and the inclination angles are α: 4.34, β: 0.00 , Γ: 0.00.

The third optical surface 18c has a free-form surface term of C ₄ : −5.2913 × 10 ⁻² , C ₆ : −2.7602 × 10 ⁻² , C ₈ : −1.5934 × 10 ⁻⁴ , C ₁₀ : 7.4192 × 10 ⁻⁴ , C ₁₁ : −1.1320 × 10 ⁻⁴ , C ₁₃ : 1.2255 × 10 ⁻⁴ , C ₁₅ : 2.1700 × 10 ⁻⁶ , and the amount of eccentricity is X: 0.00, Y: 7.41, Z: 5.02, and inclination angles are α: 73.68, β: 0.00, γ: 0.00.

The fourth optical surface 18d has free-form surface terms C ₄ : 6.8149 × 10 ⁻² , C ₆ : 9.4781 × 10 ⁻³ , C ₈ : −2.6667 × 10 ⁻³ , C ₁₀ : 2 0910 × 10 ⁻⁴ , C ₁₁ : −4.33883 × 10 ⁻⁴ , C ₁₃ : −1.7984 × 10 ⁻⁴ , and the eccentricity amounts are X: 0.00, Y: −2.87, Z: 7.35, and inclination angles are α: 119.32, β: 0.00, and γ: 0.00.

  In addition, the decentering amount on the imaging surface that is separated from the fourth optical surface 18d by a predetermined distance is X: 0.00, Y: −620.53, Z: −157.53, and the inclination angle is α: 74.99, β: 0.00, γ: 0.00.

  In the first optical surface 18a to the fourth optical surface 18d, the term relating to the free curved surface for which no data is described is zero. The unit of length is mm.

  In the present embodiment, by configuring the free-form surface prism 18 as described above, the incident pupil diameter is 1.0 mm, and the deflection angle (field angle) of the combined light by the beam scanning unit 17 is 20 ° (horizontal) × In the case of 15.07 ° (vertical), the deflection angle of the combined light emitted from the free-form surface prism 18 can be expanded to 38.35 ° (horizontal) × 27.29 ° (vertical).

  FIG. 2 is a functional block diagram showing a circuit configuration of the optical scanning projector shown in FIG. In FIG. 2, the image signal to be displayed is supplied to the control unit 21 and the synchronization signal generation unit 22. The control unit 21 generates RGB color signals based on the input image signal, drives the laser light source 2R based on the R signal, drives the laser light source 2G based on the G signal, and based on the B signal. The laser light source 2B is driven. Thereby, each modulated light of RBG which forms a color image is radiate | emitted simultaneously from laser light source 2R, 2G, 2B.

  Further, the synchronization signal generation unit 22 generates a horizontal synchronization signal and a vertical synchronization signal based on the input image signal, and based on these synchronization signals, a two-dimensional configuration that configures the beam scanning unit 17 via the driver 23. The scanning mirror 17a is driven. As a result, the RGB-modulated combined light from the reflection mirror 16 is deflected in a two-dimensional direction and is incident on the free-form surface prism 18.

  Next, the mechanical configuration of the optical scanning projector shown in FIG. 1 will be described with reference to FIGS. 3 and 4 are a perspective view and a transverse cross-sectional perspective view showing the main part of the mechanical configuration as seen from the bottom side, FIG. 5 is a perspective view seen from the top side, and FIG. 6 is a bottom view. In the present embodiment, all the optical systems except for the emission opening 19 provided in the projector casing are held by a base member 51 made of, for example, an aluminum alloy die cast. An opening 52R for attaching the laser light source 2R, the collimator lens 3R and the diaphragm 4R and an opening 52B for attaching the laser light source 2B, the collimator lens 3B and the diaphragm 4B are formed on the bottom surface of the base member 51.

  The laser light source 2R is held on the holder 53R by bonding or the like, the collimator lens 3R is held on the lens barrel 54R, and the diaphragm 4R is formed directly on one end of the lens barrel 54R. The lens barrel 54R is inserted into the opening 52R with the collimator lens 3R attached, and then the laser light source 2R is inserted into the opening 52R so as to close the opening 52R, and the holder 53R is attached to the base by the screw 55R. It is attached to the bottom surface of the member 51. The lens barrel 54R adjusts the position in the optical axis direction with respect to the laser light source 2R through an adjustment hole 56R formed on the front side of the base member 51 so as to communicate with the opening 52R. It is fixed to the opening 52R with a screw 57R.

  Similarly, the laser light source 2B is held on the holder 53B by adhesion or the like, the collimator lens 3B is held on the lens barrel 54B, and the aperture 4B is formed directly on one end of the lens barrel 54B. The lens barrel 54B is inserted into the opening 52B with the collimator lens 3B attached, and then the laser light source 2B is inserted into the opening 52B so as to close the opening 52B, and the holder 53B is attached to the base by the screw 55B. It is attached to the bottom surface of the member 51. The lens barrel 54B adjusts the position in the optical axis direction with respect to the laser light source 2B through an adjustment hole 56B formed on the front side of the base member 51 in communication with the opening 52B. It fixes to the opening part 52B with the screw 57B.

  On the front side of the base member 51, a mounting portion 61 for the total reflection prism 5, a mounting portion 62 for the dichroic prism 6, mounting portions 63 and 64 for the wedge prisms 7a and 7b, and a mounting portion 65 for the dichroic prism 8 are formed. Further, the base member 51 has two positioning portions 61a; 61b to 65a for positioning the optical frame elements in contact with the two adjacent surfaces of the optical elements to be mounted on the mounting portions 61 to 65, respectively. 65b is formed.

  Accordingly, the total reflection prism 5 is positioned and bonded and fixed in the mounting portion 61 by bringing the two adjacent surfaces into contact with the positioning portions 61a and 61b. Similarly, in the mounting portion 62, the dichroic prism 6 is positioned and bonded and fixed by bringing the two adjacent surfaces into contact with the positioning portions 62a and 62b. Similarly, the wedge prisms 7a and 7b are positioned by bringing the two adjacent surfaces of the corresponding mounting portions 63 and 64 into contact with the corresponding positioning portions 63a; 63b, 64a; 64b. Adhere and fix. Similarly, the dichroic prism 8 is positioned and bonded and fixed in the mounting portion 65 by bringing the two adjacent surfaces into contact with the positioning portions 65a and 65b. In addition, between the opening 52R and the mounting portion 61 of the total reflection prism 5, between the opening 52B and the mounting portion 62 of the dichroic prism 6, and the mounting portion 64 of the wedge prism 7b and the mounting portion 65 of the dichroic prism 8. In between, openings 67R, 67B, and 67M having sufficient sizes to allow the light beams to pass therethrough are formed.

  Similarly to the laser light sources 2R and 2B, the laser light source 2G is held on the holder 53G by adhesion or the like, and is fixed to the bottom surface of the mounting portion 71 formed integrally with the base member 51 with screws 55G via the holder 53G. The attachment portion 71 is formed so as to protrude from the upper portion of the left end portion of the base member 51 so as to extend the upper surface, and the attachment portion 71 allows the laser light emitted from the laser light source 2G to pass therethrough. A sufficiently large opening 67G is formed. Further, as shown in FIG. 3, cooling fins 68 are attached to the laser light source 2G.

  The reflection mirror 12 is bonded and fixed to the mirror support member 72. The mirror support member 72 is formed with openings 72a and 72b large enough to allow the incident light and the outgoing light to pass through the reflecting mirror 12, respectively, to be orthogonal to each other, and reflected at the portion where the openings 72a and 72b intersect. The mirror 12 is inclined and fixed by 45 degrees. The mirror support member 72 positions the opening 72a and the opening 67G formed in the attachment portion 71 of the base member 51, and fixes the mirror support member 72 to the upper surface of the attachment portion 71 with a screw 73a.

  One monoconvex lens 15a constituting the beam expander 15 is held in the lens barrel 74a. The lens barrel 74a is fixed with a screw 76a by bringing the end surface on the emission side of the single convex lens 15a into contact with a rising portion 75a formed integrally with the upper surface of the base member 51. Note that an opening 77 having a size sufficient to allow the light beam from the single convex lens 15a to pass therethrough is formed in the rising portion 75a.

  The other single convex lens 15b constituting the beam expander 15 is held in the lens barrel 74b. The lens barrel 74b is fixed to a rising portion 75b integrally formed on the upper surface of the base member 51 by adjusting the position in the optical axis direction. For this reason, the rising portion 75b has an opening 78a large enough to allow the light beam from the single convex lens 15a to pass therethrough, and communicates coaxially with the opening 78a and has a diameter larger than the opening 78a into which the lens barrel 74b is inserted. An opening 78b having a large diameter, and an adjustment hole 78c is formed on the front side of the rising portion 75b in communication with the opening 78b, and the lens barrel 74b is inserted into the opening 78b to adjust the adjustment hole 78c. After adjusting the position of the lens barrel 74b in the optical axis direction, the lens barrel 74b is fixed to the opening 78b with a screw 76b from the back side of the rising portion 75b.

  The reflection mirror 13 is bonded and fixed to the mirror support member 82 in the same manner as the reflection mirror 12. That is, the mirror support member 82 is formed with openings 82a and 82b that are large enough to allow the incident light and the outgoing light to pass through the reflecting mirror 13, respectively, at right angles, and the openings 82a and 82b intersect each other. The reflecting mirror 13 is inclined and fixed by 45 degrees. The mirror support member 82 positions the opening 82b and the opening 83 formed on the upper surface of the base member 51, and is bonded and fixed to the upper surface of the base member 51 with screws 73b.

  Next, the mounting structure of the reflection mirror 16, the two-dimensional scanning mirror 17a, and the free-form surface lens 18 will be described with reference to FIGS. 7 shows a partial exploded perspective view seen from the upper rear side of the optical scanning projector 1, and FIG. 8 shows a partial exploded perspective view seen from the bottom side of the optical scanning projector 1.

  The reflection mirror 16 and the two-dimensional scanning mirror 17a are supported by the support member 91. As shown in FIG. 7, the support member 91 is provided with a mounting slope 92a for the reflecting mirror 16 and a mounting slope 92b for the two-dimensional scanning mirror 17a, and the light flux passes through these mounting slopes 92a and 92b. A notch 93 for passing is formed. Further, two positioning pins 94a and 94b are implanted on the mounting slope 92b of the two-dimensional scanning mirror 17a. Then, the reflection mirror 16 is bonded and fixed to the mounting slope 92 a so as to straddle the notch 93. The two-dimensional scanning mirror 17a is fitted and fixed to the mounting slope 92b by fitting with two positioning pins 94a and 94b planted on the mounting slope 92b so as to straddle the notch 93. In the two-dimensional scanning mirror 17a, holes for fitting the positioning pins 94a and 94b are formed in advance on the mounting surface side.

  Further, as clearly shown in FIG. 8, the free-form surface prism 18 is formed with hook-like members 18g, 18h integrally on both side faces 18e, 18f which are non-optical surfaces, and the hook-like members 18g, 18h Openings 18i and 18j for positioning are formed respectively.

  On the other hand, the base member 51 is formed with a pair of mounting legs 101 a and 101 b that hold the free-form curved lens 18 so as to extend at the bottom of the right end portion so as to extend the bottom surface. The mounting leg portions 101a and 101b are formed such that a part of the free-form surface lens 18 is inserted between them and the hook-shaped members 18g and 18h are engaged with the mounting leg portions 101a and 101b.

  In the present embodiment, recesses 102a and 102b with which the hook-shaped members 18g and 18h of the free-form surface lens 18 are respectively engaged are formed on the bottom surfaces of the mounting legs 101a and 101b, and positioning is performed on these recesses 102a and 102b, respectively. Pins 103a and 103b for use are implanted. Further, screw holes 105a and 105b for fixing the support member 91 that supports the reflection mirror 16 and the two-dimensional scanning mirror 17a are formed in the recesses 102a and 102b. Then, the support member 91 is attached to the upper surfaces of the attachment legs 101a and 101b with fixing screws 106 through the holes 105a and 105b. The holes 105a and 105b are formed so that the heads of the fixing screws 106 do not protrude from the recesses 102a and 102b.

  In addition, the free-form surface prism 18 inserts a part of the free-form surface lens 18 between the attachment legs 101a and 101b in a state where the support member 91 is attached to the attachment legs 101a and 101b. Positioning pins 103a and 103b implanted in the recesses 102a and 102b are inserted into the positioning openings 18i and 18j formed in 18h, and the hook-shaped members 18g and 18h are engaged with the recesses 102a and 102b. In this state, the pressing plates 107a and 107b are fixed to the bottom surfaces of the mounting legs 101a and 101b with screws 108a and 108b so as to close the recesses 102a and 102b. Thus, the hook-shaped members 18g and 18h are pressed and fixed to the recesses 102a and 102b by the pressing plates 107a and 107b, and the free curved surface prism 18 is attached to the mounting legs 101a and 101b.

  As described above, in the present embodiment, the free-form surface prism 18 having a complicated shape differs from the two-side surfaces of the non-optical surface in contrast to the two-dimensional scanning mirror 17a and the free-form surface prism 18 that require high-precision positioning. The two-dimensional scanning mirror 17a is attached to the mounting legs 101a and 101b of the base member 51 via hook-shaped members 18g and 18h formed on 18e and 18f, and the two-dimensional scanning mirror 17a is a reflecting mirror that makes the combined light incident on the two-dimensional scanning mirror 17a. 16 is attached to the support member 91, and the support member 91 is attached to the attachment legs 101a and 101b. Therefore, even if the configuration is small, the two-dimensional scanning mirror 17a and the free-form surface prism 18 can be easily positioned and attached with high accuracy, so that the assembling property can be improved and the size can be easily reduced.

(Second Embodiment)
FIG. 9 is a diagram showing a schematic configuration of the optical system of the optical scanning projector according to the second embodiment of the present invention. In this optical scanning projector 111, in the configuration of the first embodiment shown in FIG. 1, the deflection directions of two one-dimensional scanning mirrors 17b and 17c are orthogonal to each other instead of the reflection mirror 16 and the two-dimensional scanning mirror 17a. It is arranged as follows. That is, in the present embodiment, the beam scanning unit 17 is configured by two one-dimensional scanning mirrors 17b and 17c. In FIG. 2, the two one-dimensional scanning mirrors 17 b and 17 c drive, for example, the one-dimensional scanning mirror 17 b via the horizontal scanning driver by the horizontal synchronization signal obtained from the synchronization signal generation unit 22, and the synchronization signal generation unit 22. For example, the one-dimensional scanning mirror 17c is driven via the vertical scanning driver by the vertical synchronization signal obtained from the above. Other configurations and operations are the same as those in FIG. 1 and FIG.

  FIG. 10 is a perspective view showing the main part of the mechanical configuration of the optical scanning projector shown in FIG. In this embodiment, in the configuration shown in FIGS. 3 to 8, a one-dimensional scanning mirror 17 b is attached to the attachment slope 92 a of the support member 91 instead of the reflection mirror 16, and two attachment slopes 92 b of the support member 91 are attached. A one-dimensional scanning mirror 17c is attached instead of the one-dimensional scanning mirror 17a. The one-dimensional scanning mirrors 17b and 17c have two positioning pins implanted on the mounting inclined surfaces 92a and 92b, respectively, similarly to the mounting structure of the two-dimensional scanning mirror 17a described in the first embodiment. The holes formed in the one-dimensional scanning mirrors 17b and 17c are fitted to the pins, and the pins are positioned and bonded and fixed to the mounting inclined surfaces 92a and 92b. Other configurations are the same as those shown in FIGS.

  Therefore, according to the present embodiment, the two one-dimensional scanning mirrors 17b and 17c constituting the beam scanning unit 17 and the free curved surface prism 18 can be easily and accurately positioned and attached. As in the case of the first embodiment, even a small configuration can improve assemblability and can be easily downsized.

(Third embodiment)
FIG. 11 is a diagram showing a schematic configuration of an optical system of an optical scanning projector according to the third embodiment of the present invention. This optical scanning projector 121 omits the reflection mirrors 12 and 13 and the beam expander 15 in the configuration of the first embodiment shown in FIG. 1, and as the laser light source 2G, similarly to the laser light sources 2R and 2B, What emits diverging light is used. The G-modulated light that is diffused and emitted from the laser light source 2G is converted into parallel light by the collimator lens 3G, then enters the prism 122 through the stop 4G, and the G-modulated light reflected by the prism 122 is converted into the dichroic prism 123. To enter. The prism 122 has a G light transmittance of 3 to 5%, for example, and the G-modulated light transmitted through the prism 122 is received by the front monitor 124 with a lens and used for controlling the emission power of the laser light source 2G. .

  R modulated light emitted from the laser light source 2R through the collimator lens 3R and the diaphragm 4R is incident on the dichroic prism 123. The dichroic prism 123 transmits the incident G-modulated light and reflects the R-modulated light substantially at right angles, thereby combining the G-modulated light and the R-modulated light, and makes the GR synthesized light enter the dichroic prism 125.

  B modulated light emitted from the laser light source 2B through the collimator lens 3B and the stop 4B is incident on the dichroic prism 125. The dichroic prism 125 transmits the incident GR combined light and reflects the B-modulated light at a substantially right angle, thereby combining the GR combined light and the B-modulated light to generate RGB combined light.

  The combined light generated by the dichroic prism 125 is sequentially incident on the two wedge prisms 7a and 7b constituting the beam shaping unit 7, so that the beam cross-sectional shape has a substantially uniform light amount distribution and a circular shape (in this embodiment). , The light beam diameter is approximately 1 mm) and then incident on the beam scanning unit 17.

  Here, similarly to the second embodiment, the beam scanning unit 17 includes two one-dimensional scanning mirrors 17b and 17c, and deflects the combined light in the two-dimensional direction by these two one-dimensional scanning mirrors 17b and 17c. . Note that the beam scanning unit 17 can also be configured with one two-dimensional scanning mirror, as in the first embodiment. The combined light deflected by the beam scanning unit 17 is enlarged by a free-form curved prism 18 and is emitted through an exit opening 19 provided in the projector housing, thereby being displayed on a display unit 20 such as a screen or a wall. Project an image by projecting light.

  Therefore, in the present embodiment, the prism 122, the dichroic prism 123, and the dichroic prism 125 constitute a color composition unit.

  12 is a cross-sectional front view showing the main part of the mechanical configuration of the optical scanning projector shown in FIG. Also in the present embodiment, as in the above-described embodiment, all the optical systems except the exit opening 19 provided in the projector housing are held by a base member 51 made of, for example, an aluminum alloy die cast. On the bottom surface of the base member 51, an opening 52G for attaching the laser light source 2G, the collimator lens 3G and the diaphragm 4G, an opening 52R for attaching the laser light source 2R, the collimator lens 3R and the diaphragm 4R, and the laser light source 2B, An opening 52B for attaching the collimator lens 3B and the diaphragm 4B is formed.

  The laser light source 2G is held on the holder 53G by adhesion or the like, the collimator lens 3G is held on the lens barrel 54G, and the aperture 4G is formed directly on one end of the lens barrel 54G. The lens barrel 54G is inserted into the opening 52G with the collimator lens 3G attached, and then the holder 53G is attached to the bottom surface of the base member 51 with a screw (not shown) so as to close the opening 52G. The lens barrel 54G, like the lens barrel 54R described in the first embodiment, is connected to the opening 52G through an adjustment hole (not shown) formed on the front side of the base member 51. The position in the optical axis direction with respect to the laser light source 2G is adjusted, and after the adjustment, it is fixed to the opening 52G with a screw (not shown) from the back side.

  The laser light source 2R, the collimator lens 3R, and the aperture 4R are fixed to the opening 52R in the same manner as in the first embodiment, and the laser light source 2B, the collimator lens 3B, and the aperture 4B are also in the same manner as in the first embodiment. And fixed to the opening 52B.

  On the front side of the base member 51, a mounting portion 161 for the prism 122, a mounting portion 162 for the dichroic prism 123, a mounting portion 163 for the dichroic prism 125, and mounting portions 164 and 165 for the wedge prisms 7a and 7b are formed. Further, the base member 51 has two positioning portions 161a; 161b to 165a; 165b that abut each of the mounting portions 161 to 165 on two adjacent surfaces of the optical element to be mounted to position the optical element. Form.

  Accordingly, the prism 122 is positioned and bonded and fixed in the mounting portion 161 by bringing the two adjacent surfaces into contact with the positioning portions 161a and 161b. Similarly, the dichroic prism 123 is positioned and bonded and fixed by bringing the two adjacent surfaces into contact with the positioning portions 162a and 162b in the mounting portion 162, and the dichroic prism 125 is positioned in the positioning portion 163a in the mounting portion 163. , 163b is positioned and bonded and fixed by bringing two adjacent surfaces into contact with each other. Similarly, the wedge prisms 7a and 7b are positioned by bringing the two adjacent surfaces of the corresponding mounting portions 164 and 165 into contact with the corresponding positioning portions 164a; 164b, 165a; 165b. Adhere and fix.

  Note that light fluxes are between the opening 52G and the mounting portion 161 of the prism 122, between the opening 52R and the mounting portion 162 of the dichroic prism 123, and between the opening 52B and the mounting portion 163 of the dichroic prism 125, respectively. Openings 167G, 167R and 167B large enough to pass through are formed. Similarly, between the mounting portion 161 and the mounting portion 162, between the mounting portion 162 and the mounting portion 163, and between the mounting portion 163 and the mounting portion 164, each of which is large enough to pass the light beam. Openings 168G, 168GR and 168M are formed.

  The front monitor 124 is fixed to the upper surface of the base member 51 with a screw (not shown) via the holding member 126 so as to receive the G-modulated light transmitted through the prism 122.

  The two one-dimensional scanning mirrors 17b and 17c and the free-form surface prism 18 constituting the beam scanning unit 17 are mounted on the base member 51 as in the second embodiment. That is, as shown in FIGS. 7, 8, and 10, the two one-dimensional scanning mirrors 17 b and 17 c are positioned and bonded and fixed to the mounting inclined surfaces 92 a and 92 b of the support member 91, and the support member 91 is The mounting legs 101 a and 101 b formed on the base member 51 are positioned on the upper surfaces and fixed with screws 106. Further, the free-form surface prism 18 is a state in which a part of the free-form surface lens 18 is inserted between the attachment legs 101a and 101b in a state where the support member 91 is attached to the attachment legs 101a and 101b. Are positioned and engaged with the recesses 102a and 102b formed in the mounting legs 101a and 101b. In this state, the presser plates 107a and 107b are respectively attached to the mounting legs 101a and 101b so as to close the recesses 102a and 102b. The bottom surface is fixed with screws 108a and 108b. Thus, the hook-shaped members 18g and 18h are pressed and fixed to the recesses 102a and 102b by the pressing plates 107a and 107b, and the free curved surface prism 18 is attached to the mounting legs 101a and 101b.

  According to the present embodiment, the same effects as those of the first embodiment and the second embodiment can be obtained, and a light source that emits divergent light is used as the laser light source 2G, similarly to the laser light sources 2R and 2B. Therefore, the reflecting mirrors 12 and 13 and the beam expander 15 shown in the first embodiment and the second embodiment are not necessary, and there is an advantage that the size can be further reduced.

  In addition, this invention is not limited only to the said embodiment, Many deformation | transformation or a change is possible. For example, in the first embodiment, the combined light from the dichroic prism 8 is reflected by the reflection mirror 6 and then incident on the two-dimensional scanning mirror 17a to be deflected. However, the reflection mirror 6 is omitted, The combined light from the dichroic prism 8 may be directly incident on the two-dimensional scanning mirror 17 a to be deflected and incident on the free-form surface prism 18. Therefore, in this case, only the two-dimensional scanning mirror 17a may be positioned and attached to the support member 91. The positioning pins and holes for positioning the free-form curved prism 18 on the base member 51 can be provided with positioning pins on the free-form curved prism 18 side and holes on the base member 51 side. Similarly, positioning pins and holes for positioning the two-dimensional scanning mirror 17a and the one-dimensional scanning mirrors 17b and 17c on the support member 91 are positioned on the two-dimensional scanning mirror 17a and the one-dimensional scanning mirrors 17b and 17c. A hole can also be provided on the support member 91 side.

  In the first and second embodiments, the total reflection prism 5 can be changed to a reflection mirror and the dichroic prisms 6 and 8 can be changed to dichroic mirrors. Similarly, in the third embodiment, the prism 122 can be changed to a half mirror, and the dichroic prisms 123 and 125 can be changed to dichroic mirrors. Furthermore, the light source that generates each color light of RGB is not limited to the semiconductor laser and the DPSS laser, and various light sources such as a light emitting diode can be used. The free-form surface prism 18 can also be configured to emit the combined light from the beam scanning unit 17 as parallel light with an enlarged polarization angle without having an imaging function.

1 is a diagram illustrating a schematic configuration of an optical system of an optical scanning projector according to a first embodiment of the present invention. FIG. 2 is a functional block diagram showing a circuit configuration of the optical scanning projector shown in FIG. 1. It is the perspective view seen from the bottom face side which shows the principal part of the mechanical structure of the optical scanning projector shown in FIG. It is a cross-sectional perspective view of FIG. FIG. 4 is a perspective view of the optical scanning projector shown in FIG. 3 viewed from the upper surface side. FIG. 4 is a bottom view of the optical scanning projector shown in FIG. 3. FIG. 4 is a partial exploded perspective view of the optical scanning projector shown in FIG. 3 viewed from the upper back side. FIG. 4 is a partial exploded perspective view of the optical scanning projector shown in FIG. 3 viewed from the bottom side. It is a figure which shows schematic structure of the optical system of the optical scanning projector which concerns on 2nd Embodiment of this invention. It is a perspective view which shows the principal part of the mechanical structure of the optical scanning projector shown in FIG. It is a figure which shows schematic structure of the optical system of the optical scanning projector which concerns on 3rd Embodiment of this invention. FIG. 12 is a cross-sectional front view showing the main part of the mechanical configuration of the optical scanning projector shown in FIG. 11.

Explanation of symbols

1, 111, 121 Optical scanning projector 2R, 2G, 2B Laser light source 3R, 3G, 3B Collimator lens 4R, 4G, 4B Aperture 5 Total reflection prism 6, 8 Dichroic prism 7 Beam shaping unit 7a, 7b Wedge prism 11a Semiconductor laser 11b SHG optical system 12, 13 Reflection mirror 15 Beam expander 15a, 15b Monoconvex lens 16 Reflection mirror 17 Beam scanning unit 17a Two-dimensional scanning mirror 17b, 17c One-dimensional scanning mirror 18 Free-form surface prism 18a-18d Optical surface 18e, 18f Side surface (Non-optical surface)
18g, 18h bowl-shaped member 18i, 18j opening 19 exit opening 20 display unit 21 control unit 22 synchronization signal generation unit 23 driver 51 base member 52R, 52G, 52B opening 53R, 53G, 53B holder 54R, 54G, 54B lens barrel 56R , 56B Adjustment hole 61-65 Mounting part 61a; 61b-65a; 65b Positioning part 71 Mounting part 72, 82 Mirror support member 74a, 74b Lens barrel 75a, 75b Raising part 91 Support member 92a, 92b Mounting slope 93 Notch Portions 94a, 94b Pins 101a, 101b Mounting legs 102a, 102b Recesses 103a, 103b Pins 105a, 105b Holes 107a, 107b Holding plate 122 Prism 123, 125 Dichroic prism 124 Front monitor 126 Holding member 61-165 mounting portion 161a; 161b~165a; 165b positioning unit

Claims (3)

A light source unit that generates a plurality of different color lights modulated based on an image signal, a color synthesis unit that coaxially synthesizes a plurality of color lights from the light source unit, and a synthesized light synthesized by the color synthesis unit, A beam scanning unit that deflects in a two-dimensional direction according to the image signal and a plurality of non-rotating target-shaped optical surfaces, and at least a deflection angle of the combined light deflected by the beam scanning unit is increased. A free-form surface prism for projecting and displaying an image, and a base member holding at least the beam scanning unit and the free-form surface prism,
The beam scanning unit is attached to a support member, the support member is fixed to the base member, and the free-form curved prism is fixed to the base member via a hook-shaped member formed on a non-optical surface, An optical scanning type projector configured to position a beam scanning unit and the free-form curved prism. The beam scanning unit has a two-dimensional scanning mirror,
The support member is provided with a reflection mirror that reflects the combined light combined by the color combining unit and makes it incident on the two-dimensional scanning mirror.
The optical scanning projector according to claim 1. The beam scanning unit includes two one-dimensional scanning mirrors that deflect the combined light combined by the color combining unit in directions orthogonal to each other.
The optical scanning projector according to claim 1.

Images