A projection display device

Abstract

This invention relates to a projection display device. In the field of projection image display devices that modulate and project lasers based on image signals, there is a need for a small, easy-to-drive and control device with high light utilization efficiency. This projection display device includes: a plurality of semiconductor lasers; a collimating lens for collimating a plurality of laser beams output from the plurality of semiconductor lasers; an integrator illumination system for superimposing the plurality of laser beams collimated by the collimating lens to form a rectangular illumination area; a deflection device disposed closer to the collimating lens than the position where the rectangular illumination area is formed by the integrator illumination system; a transfer optics system for magnifying and transferring the rectangular illumination area, which has been deflected and scanned by the deflection device, onto a reflective light modulator; and a projection lens for projecting the image light output from the reflective light modulator.

Description

Technical Field

[0001] This invention relates to a projection display device equipped with a light source. Background Technology

[0002] A projection display device that uses lasers has been known for some time.

[0003] Patent document 1 discloses a projection display device comprising: a laser light source; an acousto-optic modulator for optically modulating the laser according to an image signal; a polygonal reflector for horizontally scanning the modulated laser; and a galvanometer reflector for vertically scanning.

[0004] Patent Document 1: Japanese Patent Publication No. 2000-180759

[0005] In the projection display device described in Patent Document 1, there is an optical scanning unit that uses a polygonal reflector for horizontal scanning and a galvanometer reflector for vertical scanning at the same time. Since it scans optically in both horizontal and vertical directions, it requires a large optical path space, which leads to the problem of device enlargement.

[0006] Therefore, in the field of projection image display devices that modulate and project lasers based on image signals, there is a desire to realize a small, easy-to-drive and control device with high light utilization efficiency. Summary of the Invention

[0007] A first aspect of the present invention is a projection display device, characterized in that it comprises: a plurality of semiconductor lasers; a collimating lens for collimating a plurality of laser beams output from the plurality of semiconductor lasers; an integrator illumination system for superimposing the plurality of laser beams collimated by the collimating lens to form a rectangular illumination area; a deflection device disposed closer to the collimating lens than the position where the rectangular illumination area is formed by the integrator illumination system; a transfer optics system for magnifying and transferring the rectangular illumination area, which has been deflected and scanned by the deflection device, onto a reflective light modulation device; and a projection lens for projecting image light output from the reflective light modulation device.

[0008] According to the present invention, in the field of projection image display devices that modulate and project lasers based on image signals, a small, easy-to-drive and control device with high light utilization efficiency can be realized. Attached Figure Description

[0009] Figure 1 This is a diagram showing the outline structure of the optical system of the projection display device according to Embodiment 1.

[0010] Figure 2(a) is a typical diagram illustrating a pair of semiconductor lasers and collimating lenses contained in a laser module LM; Figure 2 (b) is a typical diagram showing a paired laser module LM with 4×2 semiconductor lasers 11 arranged with collimating lenses 102.

[0011] Figure 3 (a) is a diagram illustrating the near-field pattern of the output light of semiconductor laser 11; Figure 3 (b) is a diagram illustrating the far-field pattern of the output light of semiconductor laser 11.

[0012] Figure 4 (a) is a diagram showing the beam spread in the parallel direction; Figure 4 (b) is a diagram showing the beam spread for orthogonal directions.

[0013] Figure 5 (a) is a diagram of the integrator lighting system INT viewed from one direction; Figure 5 (b) is from and Figure 5 (a) A diagram of the integrator lighting system INT viewed from the orthogonal direction of phase; Figure 5 (c) is a diagram showing the microlens array pair; Figure 5 (d) is a diagram showing the rectangular lighting area IM1.

[0014] Figure 6 (a) is a perspective view showing the appearance of an example of deflector 210; Figure 6 (b) is a side view of the deflector 210.

[0015] Figure 7 (a) is a cross-sectional view used to illustrate the position and tilt angle of the reflecting surface of the deflector 210;

[0016] Figure 7 (b) is a diagram used to illustrate the position and tilt angle of the reflecting surface of the deflector 210.

[0017] Figure 8 (a) is a diagram showing the positional relationship between the deflector 210 and the rectangular illumination area IM1; Figure 8 (b) is an enlarged view of the area near the beam illumination position 214 on the reflecting surface; Figure 8 (c) is a diagram showing the blue rectangular illumination area IM1 being deflected and scanned in the DB direction.

[0018] Figure 9 (a) is a typical diagram used to illustrate the function of the front transpilation lens 201 and the rear transpilation lens 202; Figure 9 (b) is a graph showing the relationship between the image of the reflective light modulator 340 and the rectangular laser beam scanning range SA; Figure 9 (c) is a diagram showing the illumination of the screen of the reflective light modulator 340 by rectangular B beams, G beams and R beams, with the horizontal axis as the time axis.

[0019] Figure 10 This is a diagram showing the outline structure of the optical system of the projection display device according to Embodiment 2.

[0020] Figure 11 This is a diagram used to illustrate the integrator lighting system according to Embodiment 3.

[0021] Figure 12 (a) is a diagram of the integrator lighting system INT according to embodiment 3 as viewed from one direction; Figure 12 (b) is from and Figure 12 (a) A diagram of the integrator lighting system INT involved in Implementation Method 3, viewed from the orthogonal direction; Figure 12 (c) is a diagram showing the rectangular lighting area IM1.

[0022] Figure 13 (a) is a diagram showing a solid (balk) light bar used in an integrator lighting system;

[0023] Figure 13 (b) is a diagram showing a hollow light bar used in an integrator lighting system.

[0024] Figure 14 This is a diagram showing the outline structure of the optical system of the projection display device according to Embodiment 3.

[0025] Figure 15 This is a diagram showing the positional relationship between the deflector and the rectangular illumination area IM1 in Embodiment 3.

[0026] Figure 16 This is a diagram showing the outline structure of the optical system of the projection display device according to Embodiment 4.

[0027] Figure 17 (a) is a diagram of the deformable optical system that can be used in each embodiment, viewed from one direction;

[0028] Figure 17 (b) is from and Figure 17 (a) A diagram of the deformable optical system that can be used in various embodiments, viewed in the orthogonal direction.

[0029] Explanation of reference numerals in the attached figures

[0030] 11... Semiconductor lasers

[0031] 12……Light-emitting part

[0032] 100B...B light source

[0033] 100G...G light source

[0034] 100R...R light source

[0035] 102……collimating lens

[0036] 103, 104... microlens array

[0037] 106……Condensing Lens

[0038] 190… Projection screen

[0039] 201……Front-side projection lens

[0040] 202……Rear-side projection lens

[0041] 210... Deflector

[0042] 210B...B uses a deflector

[0043] 210G...G uses a deflector

[0044] 210R……R uses a deflector

[0045] 211……Matrix

[0046] 212……Motor

[0047] 213……Reflecting surface

[0048] 214……Beam Illumination Position

[0049] 220...Photosynthesis Department

[0050] 221, 222... Dichroic mirrors

[0051] 310a...diffuser plate

[0052] 320…Second Transmission Optical System

[0053] 321……First illumination lens

[0054] 322……Second Illumination Lens

[0055] 330... Optical Path Conversion Mirror

[0056] 340...Reflective optical modulation device

[0057] 350…TIR prism

[0058] 360... Projection Lens

[0059] 400…light source

[0060] 400B...B light source

[0061] 400G...G light source

[0062] 400R...R light source

[0063] 401... Condensing Lens

[0064] 402...Diffusion device

[0065] 403……Light Rod

[0066] 406...Relay Lens

[0067] 406a... Anterior convex lens

[0068] 406b...rear convex lens

[0069] 407a... Concave lens

[0070] 407b...convex lens

[0071] 1000, 1001, 1002, 1003... Projection display devices Detailed Implementation

[0072] The projection display device according to an embodiment of the present invention will now be described with reference to the accompanying drawings.

[0073] Furthermore, the embodiments shown below are illustrative examples. For instance, those skilled in the art can make appropriate modifications to the technical solutions for the details without departing from the spirit of the invention. Additionally, in the accompanying drawings referenced in the following embodiments and descriptions, unless otherwise specified, units denoted by the same reference numerals have the same function. Furthermore, the optical components in the figures are typically shown, therefore their actual shapes and structures are not necessarily faithfully represented. For example, even if depicted as a single lens in the drawings, it may be composed of multiple lenses unless otherwise specified.

[0074] In the following explanation, for example, when denoted as the positive X direction, it points in the same direction as the X-axis arrow in the illustrated coordinate system; when denoted as the negative X direction, it points in the opposite direction, 180 degrees from the X-axis arrow in the illustrated coordinate system. Furthermore, when simply denoted as the X direction, it refers to a direction parallel to the X-axis, regardless of whether it is the same as the X-axis arrow in the illustrated coordinate system. The same applies to directions other than X.

[0075] Furthermore, in the following description, red is sometimes referred to as "R", green as "G", and blue as "B". Therefore, for example, R light and red light, G light source and green light source, and B laser and blue laser are synonymous.

[0076] [Implementation Method 1]

[0077] Figure 1 This is a diagram showing the outline structure of the optical system of the projection display device according to Embodiment 1. For ease of explanation, the mechanical structure, body, electrical wiring, etc., used to mount the optical components are omitted in this diagram.

[0078] [Overall Structure]

[0079] The projection display device 1000 includes a B light source 100B, a G light source 100G, an R light source 100R, a B deflector 210B, a G deflector 210G, an R deflector 210R, a light combining unit 220, a light path conversion mirror 330, a total internal reflection (TIR) ​​prism 350, a reflective light modulator 340, and a projection lens 360. Furthermore, a front transflection lens 201 is disposed between the light sources of various colors and the deflectors of various colors, and a rear transflection lens 202 is disposed between the light combining unit 220 and the light path conversion mirror 330. The light combining unit 220 includes a dichroic mirror 221 and a dichroic mirror 222. Optionally, the projection display device 1000 may include a projection screen 190.

[0080] Specifically, the B light source 100B is equipped with a semiconductor laser that emits B light, the G light source 100G is equipped with a semiconductor laser that emits G light, and the R light source 100R is equipped with a semiconductor laser that emits R light. The light sources will be described in detail later.

[0081] B-type deflector 210B deflects the B light emitted by B-source 100B in the DB direction. Similarly, G-type deflector 210G deflects the G light emitted by G-source 100G in the DG direction, and R-type deflector 210R deflects the R light emitted by R-source 100R in the DR direction. The deflectors will be described in detail later.

[0082] The light combining unit 220 includes a dichroic mirror 221 and a dichroic mirror 222. The dichroic mirror 221 has the optical characteristic of transmitting G light and reflecting B light. The dichroic mirror 222 has the optical characteristic of transmitting both G and B light and reflecting R light. Each optical element is configured such that the optical axis center of the front transflector lens 201 for B light overlaps with the optical axis center of the front transflector lens 201 for G light on the dichroic mirror 221. Furthermore, each optical element is configured such that the optical axis centers of the front transflector lens 201 for B light, the front transflector lens 201 for G light, and the front transflector lens 201 for R light overlap on the dichroic mirror 222.

[0083] Through the light combining unit 220, the travel directions of the B-beam (dashed line), G-beam (solid line), and R-beam (single-dot dashed line) are all unified to the positive Z-direction, but these lights are combined in a way that they do not overlap with each other at any time. This is because the deflection scanning timing (deflection phase) of the B-beam deflector 210B, the G-beam deflector 210G, and the R-beam deflector 210R is controlled so that each of the B-beam, G-beam, and R-beam does not overlap with each other on the screen of the reflective light modulator 340. The scanning method will be described in detail later.

[0084] The B, G, and R rays emitted from the photosynthesis unit 220 are redirected to the positive X direction by the optical path conversion mirror 330 and then incident on the TIR prism 350.

[0085] The TIR prism 350 is, for example, an internal total internal reflection prism composed of two prisms, which causes the illumination light (B light, G light, R light) to undergo total internal reflection at the air gap surface and be incident on the reflective light modulator 340 at a predetermined angle. As mentioned above, the B light, G light, and R light illuminate a portion of the image of the reflective light modulator 340 in a non-overlapping manner.

[0086] The reflective light modulator 340, for example, uses a digital micromirror device (DMD) with micromirrors arranged in an array. Each micromirror corresponding to a display pixel is driven according to the brightness level of the image signal, causing its reflection direction to change through pulse width modulation. However, other types of reflective light modulators, such as reflective liquid crystal devices, can also be used.

[0087] Pixels in the image area illuminated by B light are driven according to the brightness level of the B component of the image signal, reflecting the B image light towards the TIR prism 350 at a predetermined angle. Similarly, pixels in the image area illuminated by G light are driven according to the brightness level of the G component of the image signal, reflecting the G image light towards the TIR prism 350 at a predetermined angle. Additionally, pixels in the image area illuminated by R light are driven according to the brightness level of the R component of the image signal, reflecting the R image light towards the TIR prism 350 at a predetermined angle. In this way, the modulation operation of the reflective light modulator is synchronized with the deflection scanning of the B deflector 210B, G deflector 210G, and R deflector 210R.

[0088] Image light (B image light, G image light, R image light) is transmitted from TIR prism 350 and guided to projection lens 360, where it is projected as a color image. Projection lens 360 consists of one or more lenses and may also have automatic focus adjustment and zoom functions.

[0089] The projection screen 190 is used when constructing a rear-projection display device. Furthermore, although it is often installed in front-projection scenarios, it is not necessarily required when the user projects onto any wall or other surface.

[0090] [light source]

[0091] The following describes light sources B 100B, G 100G, and R 100R. Specifically, light source B 100B includes a laser module LM-B, light source G 100G includes a laser module LM-G, and light source R 100R includes a laser module LM-R. Laser module LM-B includes a semiconductor laser emitting B light and a collimating lens; laser module LM-G includes a semiconductor laser emitting G light and a collimating lens; and laser module LM-R includes a semiconductor laser emitting R light and a collimating lens. Except for the emission wavelength of the semiconductor laser, the basic structure of the light sources of various colors is the same. Therefore, in the following description, they are sometimes referred to as light source 100 without distinguishing between each color of light.

[0092] (Laser module)

[0093] The light source 100 is equipped with a laser module LM, in which semiconductor lasers and collimating lenses are arranged in a one-dimensional or two-dimensional array.

[0094] Figure 2 (a) is a typical diagram illustrating a pair of semiconductor lasers and collimating lenses included in a laser module LM. 11 is the semiconductor laser, and 12 is the light-emitting portion of the semiconductor laser 11. Additionally, in Figure 2 In (a), according to Figure 1The B-light source 100B is configured to display the direction of the XYZ coordinate system. Figure 2 In (a), it is shown that the long side direction H of the light-emitting part 12 is parallel to the Y direction, and the direction of light emitted from the light-emitting part 12 is parallel to the Z direction.

[0095] The long side direction H of the light-emitting portion 12 is typically the direction in which the active layer extends between the P-type cladding and the N-type cladding on the side of the semiconductor chip constituting the semiconductor laser 11. For example... Figure 2 As shown in (a), in the following description, the direction parallel to the long side direction H of the light-emitting part 12 of the semiconductor laser 11 is sometimes referred to as the "parallel direction" or the slow axis, and the direction orthogonal to the long side direction of the light-emitting part 12 is referred to as the "orthogonal direction" or the fast axis. Linearly polarized light is emitted from the semiconductor laser 11, and the vibration direction of its electric field is the parallel direction (Y direction).

[0096] It is known that the angular characteristics of the output light of semiconductor laser 11 vary depending on the emission direction. Figure 3 The near-field pattern of the output light is illustrated in (a). Figure 3 Example (b) illustrates the far-field pattern of the output light.

[0097] like Figure 3 As shown in (a), in the near-field pattern, this can be seen as a beam profile reflecting the shape (long side, short side) of the emitting part. On the other hand, as the beam travels, as... Figure 3 As illustrated in the far-field pattern of (b), the beam gradually expands. That is, viewed from the parallel direction, the beam emitted from the semiconductor laser 11 shows a smaller expansion, traveling within a narrow angular range in a pattern of uniform intensity distribution. On the other hand, viewed from the orthogonal direction, the beam emitted from the semiconductor laser 11 forms a mountain-shaped (Gaussian) intensity distribution pattern, expanding over a wider angular range than the parallel direction as it travels. This is because the active layer of the semiconductor laser is thinner in the orthogonal direction, thus experiencing a greater influence from diffraction during emission. The parallel direction, where the expansion is smaller in the far-field pattern, can also be called the slow axis, and the orthogonal direction, where the expansion is larger, can be called the fast axis.

[0098] In this embodiment, such as Figure 2 As shown in (a), a collimating lens 102 (first collimating lens) is used to shape the laser beam output from the semiconductor laser 11. That is, the light emitted from the light-emitting part 12 with a length of Hy1 in the long side direction is collimated by the collimating lens 102, becoming a beam with an elliptical cross-section that travels in the Z direction. Furthermore, the major axis of the ellipse is parallel to the X direction, and the minor axis is parallel to the Y direction.

[0099] Even when passing through collimating lens 102, the light beam will not be perfectly parallel to the optical axis (Z direction). The beam spreads differently in the parallel direction (long side of the light-emitting part) and the orthogonal direction (short side of the light-emitting part). (Reference) Figure 4 (a) and Figure 4 (b) explains the different ways in which the light beam expands after passing through the collimating lens 102. Figure 4 (a) shows the extension for the parallel direction. Figure 4 (b) shows the extension for the orthogonal direction.

[0100] like Figure 4 As shown in (a), although the top of the beam intensity is flat when viewed from the parallel direction, the beam diameter expands as it moves towards the Z direction, therefore the divergence angle cannot be considered good. In contrast, as... Figure 4 As shown in (b), if viewed from the orthogonal direction, it can be seen that even if the distance from the collimating lens 102 changes, the changes in beam intensity distribution and beam diameter are very small. That is, the laser beam transmitted from the collimating lens 102 has higher parallelism in the orthogonal direction (fast axis of the semiconductor laser) than in the parallel direction (slow axis of the semiconductor laser), and has a good divergence angle.

[0101] As described later, in this invention, the light modulation device is illuminated by deflecting and scanning the light beam along the orthogonal direction (the direction of the shorter side of the rectangle) by utilizing the property that the divergence angle of the light beam output from the light source 100 is excellent in the orthogonal direction (the direction of the shorter side of the rectangle) (high parallelism of the light beam). This is because deflecting and scanning the light beam along the direction of excellent divergence angle helps to prevent overlap of the illumination areas of various colors B, G, and R on the screen of the light modulation device.

[0102] The light source 100 has a laser module LM, which includes multiple semiconductor lasers paired with a collimating lens 102 (first collimating lens). Figure 2 (b) is a typical diagram showing a paired laser module LM with 4×2 semiconductor lasers 11 arranged with collimating lenses 102. Furthermore, in Figure 2 In (b), according to Figure 1 A 100B B light source is used to display the direction of the XYZ coordinate system.

[0103] In the laser module LM, multiple semiconductor lasers are configured to be arranged at equal intervals along the Y direction. Furthermore, each semiconductor laser is arranged along the Y direction with the long side of the light-emitting section 12 in the same direction. Although an example using 4×2 semiconductor lasers is shown, the number of devices is not limited to this example. The laser module LM can also be configured to arrange multiple semiconductor lasers in a single column or in three or more columns along the Y direction. Even in a light source 100 with one or more columns of semiconductor lasers along the Y direction, the output beam exhibits a better divergence angle in the short side direction of the light-emitting section than in the long side direction.

[0104] (Integrator illumination system / Optical overlap unit)

[0105] The light source 100 in this embodiment includes an integrator illumination system INT, which is used to superimpose multiple laser beams emitted from the laser module LM to form a rectangular illumination area. (See reference...) Figure 5 (a)~ Figure 5 (d) describes the integrator lighting system INT.

[0106] The laser beams emitted from each of the semiconductor lasers 11 included in the laser module LM are made approximately parallel by the collimating lens 102, with the divergence angle as already explained. To form Figure 5 The rectangular illumination area IM1 shown in (d) of this embodiment has an integrator illumination system INT that superimposes the laser beams emitted from each semiconductor laser.

[0107] like Figure 5 of (a), Figure 5 As shown in (b), the integrator illumination system INT includes a microlens array 103, a microlens array 104, and a condenser lens 106. The microlens array 103 and the microlens array 104 are configured in pairs.

[0108] like Figure 5 As shown in (c), when viewed along the direction of the laser beam (Z direction in this figure), microlenses of size V0 in the X direction and size H0 in the Y direction are arranged in a two-dimensional manner along the XY plane in each microlens array. The incident surface of each microlens in microlens array 103 and the exit surface of each microlens in microlens array 104 are spherical. Furthermore, the exit surface of each microlens in microlens array 103 and the incident surface of each microlens in microlens array 104 are flat surfaces. The focal lengths of each microlens in microlens array 103 and microlens in microlens array 104 are set so that they can image onto each other at spherical positions.

[0109] The laser beam passing through the microlens array 103 and microlens array 104 is focused by the condensing lens 106, such as Figure 5 As shown in (d), a rectangular lighting area IM1 with a length of V1 in the X direction and a length of H1 in the Y direction is formed.

[0110] Compared to light sources such as bulbs, the semiconductor laser 11 has a better divergence angle. Therefore, for example, if the spacing between the microlenses is set to a range of 0.05 mm to 0.5 mm, a rectangular illumination area IM1 with V1 or H1 of about 1 mm to 2 mm can be obtained. The long side of the rectangular illumination area IM1 corresponds to the parallel direction (the slow axis direction of the semiconductor laser), and the short side corresponds to the orthogonal direction (the fast axis direction of the semiconductor laser). The beam output from the light source 100 has a better divergence angle in the short side direction of the rectangle than in the long side direction. In this embodiment, a microlens array pair is used, in which microlenses having spherical and flat surfaces are arranged in an array. However, depending on the situation, a compound eye lens pair, in which lenses with curved incident and exit sides are arranged in an array, may also be used. Alternatively, if the divergence angle of the light source is good (NA is small), a single-plate microlens array may be used instead of a pair.

[0111] (Deflector)

[0112] like Figure 1 As shown, deflectors (deflector 210B for B, deflector 210G for G, and deflector 210R for R) are arranged between the light source 100 (light source B 100B, light source G 100G, and light source R 100R) and the rectangular illumination area IM1 they illuminate respectively.

[0113] The following describes deflector 210B for B, deflector 210G for G, and deflector 210R for R. Although they are deflection devices used to deflect and scan laser beams of different colors, they have the same basic structure, so in the following text, they are sometimes referred to as deflector 210 without specifying the color.

[0114] Figure 6 (a) is a perspective view showing the appearance of an example of deflector 210. Figure 6 (b) is a side view of the deflector 210.

[0115] The deflector 210 includes a rotatable circular plate-shaped base 211 and a motor 212 that rotates the base 211 around a rotation axis AX. A reflective surface 213, serving as a strip-shaped optical surface, is provided along the circumference of the main surface of the circular plate-shaped base 211. Here, to specify the position of the reflective surface, as... Figure 6As shown in (a), the angular coordinates are set by rotating counterclockwise around the rotation axis AX (0°, 90°, 180°, and 270° are shown in the figure). Additionally, the axis BX shown in the figure is parallel to the rotation axis AX and passes through the reflecting surface 213. The beam illumination position 214 shows the position of the beam output from the light source 100 when it is reflected before reaching the rectangular illumination area IM1.

[0116] The strip-shaped reflective surface 213 is twisted such that the angle relative to axis BX (i.e., rotation axis AX) varies with position. (Reference) Figure 7 (a) and Figure 7 (b) explains the angle of the reflecting surface. Figure 7 (a) and Figure 7 In (b), the position of the reflecting surface is shown as that of the surface formed by... Figure 6 The position is defined by the angular coordinates described in (a). In addition, the tilt angle of the reflecting surface is shown as the tilt angle of the reflecting surface when the main surface of the circular plate-shaped substrate 211 (i.e., the surface orthogonal to axis BX) is used as a reference.

[0117] like Figure 7 As shown in (b), the reflecting surface 213 is configured such that the tilt angle of the reflecting surface varies linearly with respect to the position of the reflecting surface. Figure 6 of (a), Figure 7 As shown in (b), when the reflective surface is at 0° (360°), the tilt angle of the reflective surface is discontinuous. Therefore, for ease of explanation, in Figure 7 (a) shows the tilt angles when the reflective surface is at 1° and 359°.

[0118] When the motor rotates the base 211 along the R direction, the reflective surface 213 also rotates around the rotation axis AX, therefore... Figure 6 At position 214 where the laser beam is irradiated, as shown in (a), the angular coordinates of the part irradiated by the laser beam change continuously in the manner of 0°→90°→180°→360°(=0°)→90°…….

[0119] Even if the rotation of the reflecting surface causes a change in the part of the reflecting surface irradiated by the laser beam, such as Figure 7 As shown in (a), the incident beam always strikes the reflecting surface 213 at an angle α relative to the axis BX. On the other hand, depending on the position of the reflecting surface, the tilt angle of the reflecting surface varies from -θ to +θ. Therefore, as... Figure 7As shown in (a), when the axis BX is taken as a reference, the direction of the laser beam reflected by the reflecting surface 213 varies within an angle range of 4θ from (α-2×θ) to (α+2×θ). That is, the tilt angle is configured such that when the optical surface (reflecting surface) is continuously rotated at a certain speed, the laser beam is recursively deflected in a certain direction at a certain deflection speed.

[0120] In other words, such as Figure 6 As shown in (b), deflector 210 enables the emitted beam to be deflected and scanned within an angular range from RD1 (relative to axis BX(α-2×θ)) to RD2 (relative to axis BX(α+2×θ)). Along... Figure 6 When the R direction of (a) causes the reflecting surface 213 to rotate continuously, the emitted beam from Figure 6 (b) The beam continuously deflects (scans) from RD1 toward RD2, instantly returns to RD1 upon reaching RD2, and then deflects (scans) toward RD2 again. Additionally, if the reflecting surface 213 is rotated in the opposite direction to R, the emitted beam will... Figure 6 (b) RD2 continuously deflects towards RD1 (scanning), and upon reaching RD1, it instantly returns to RD2 and deflects towards RD1 again (scanning).

[0121] Thus, by using the deflector 210, a simple driving method that allows the rotating body to rotate continuously at a certain speed can be used to recursively deflect and scan the laser beam at an equal speed in a predetermined direction. As will be described later, by controlling the motor 212 to rotate synchronously with the driving timing of the reflective light modulator 340 (or the image signal input to the reflective light modulator 340), the illumination light can be scanned in the V direction within the image of the reflective light modulator 340.

[0122] Furthermore, in implementing this invention, a galvanometer reflector can be used instead of the deflector 210 with a rotating body. However, using a galvanometer reflector is expected to result in a larger device, vibration, and increased cost, so it is preferable to use the deflector 210 with a rotating body.

[0123] exist Figure 8 (a) shows the positional relationship between the deflector 210 and the rectangular illumination area IM1. The coordinate system is shown with reference to light source B 100B. Additionally, in Figure 8 (b) shows an enlarged view of the beam illumination position 214 of the reflective surface. The beam illumination position 214 of the reflective surface is positioned closer to the light source side at a distance L compared to the rectangular illumination area IM1. Figure 8 As shown in (c), the blue rectangular illumination area IM1 is deflected and scanned in the DB direction as the deflector 210 rotates.

[0124] Furthermore, the manufacturing method of the deflector 210 will be described incidentally. The circular plate-shaped substrate 211, with a strip-shaped reflective surface 213 arranged along its circumference, can be manufactured at low cost, for example, by processing the metal base material using a stamping process. Figure 7 As illustrated in (a), there are protruding and recessed portions from the main surface of the substrate 211 near the reflective surface 213. To ensure good rotational balance, it is preferable that the cross-section at any position is of equal cross-sectional area when viewed from the section passing through the rotation axis AX. Furthermore, to reduce wind noise, the maximum height of the protrusion from the main surface of the substrate 211 and the maximum depth of the recess are preferably 3 / 4 or less of the average plate thickness. Specifically, the average plate thickness of the substrate 211 is preferably 0.7 mm or more and 2 mm or less, and θ is preferably 3° or more and 6° or less.

[0125] Using the deflector described above, such as Figure 1 As shown, rectangular illumination areas IM1 of various colors formed by laser beams of B, G, and R are deflected and scanned in the directions of DB, DG, and DR, respectively.

[0126] (Photosynthesis Department)

[0127] The direction of travel of laser beams of various colors is unified by the light synthesis unit 220, and the function of the light synthesis unit 220 is as explained in the overall structure section.

[0128] (Transfer Optical System)

[0129] The rectangular illumination area IM1 formed by laser beams of various colors is magnified and projected onto the screen of the reflective light modulator 340 through the first transfer lens 200 (first transfer optical system), which consists of a front transfer lens 201 and a rear transfer lens 202 for various colors. Both the front transfer lens 201 and the rear transfer lens 202 are convex lenses with positive optical power.

[0130] Figure 9 Figure (a) is a typical diagram used to illustrate the function of the front transpilation lens 201 and the rear transpilation lens 202. As shown, the rectangular illumination area IM1 is magnified and transpiled into a rectangular secondary transpilation image IM2. Figure 1 As shown, the rectangular secondary image IM2 is set at the screen position of the reflective light modulator 340. The magnification of the rectangular illumination area IM1 to the rectangular secondary image IM2 is, for example, about 6 times (V1:V2 = 1:6).

[0131] exist Figure 9(b) illustrates the relationship between the image of the reflective light modulator 340 and the rectangular laser beam scanning range SA. If the image size of the reflective light modulator 340 is set to H (horizontal direction) × V (vertical direction), the rectangular laser beam scanning range SA covers an area H' × V' larger than the image size. Furthermore, the rectangular laser beam scanning range SA is magnified by the aforementioned transfer magnification relative to the scanning range of the rectangular illumination area IM1 scanned by the deflector 210.

[0132] Figure 9 (c) is a diagram showing the illumination of the screen of the reflective light modulator 340 by rectangular B-beams, G-beams, and R-beams, with the horizontal axis as the time axis. The B-beams, G-beams, and R-beams vertically scan the screen of the reflective light modulator 340 along the scanning direction SD, completing one frame scan in one frame time. The B-beams, G-beams, and R-beams are configured to be non-overlapping to avoid color mixing at the boundaries of various color regions, and the vertical width V2 of each beam is necessarily configured to be less than 1 / 3 of V'. The vertical width of each beam can be set to be more than 1 / 6 and less than 1 / 3 of the vertical width of the screen of the reflective light modulator 340.

[0133] As described above, the projection display device of this embodiment is provided with an illumination component for each different color of light and has a light combining unit. The illumination component includes multiple semiconductor lasers, collimating lenses, an integrator illumination system and a deflection device. The light combining unit combines the illumination light output by the illumination components of different colors of light. The rectangular illumination area output by each of the illumination components of different colors of light is deflected and scanned in a non-overlapping manner and magnified and projected onto a reflective light modulation device.

[0134] According to this embodiment, in the field of projection image display devices that modulate and project lasers based on image signals, a small, easy-to-drive and control device with high light utilization efficiency can be realized.

[0135] [Implementation Method 2]

[0136] Figure 10 This is a diagram showing the outline structure of the optical system of the projection display device according to Embodiment 2. For ease of explanation, the mechanical structure, body, electrical wiring, etc., used for mounting the optical components are omitted in this diagram. Items common to Embodiment 1 are simplified or omitted in the description.

[0137] [Overall Structure]

[0138] The projection display device 1001 of this embodiment is the same as that of Embodiment 1 in that it includes a B light source 100B, a G light source 100G, an R light source 100R, a B deflector 210B, a G deflector 210G, an R deflector 210R, a first transflection lens 200 composed of a front transflection lens 201 and a rear transflection lens 202, a light combining unit 220, a light path conversion mirror 330, a TIR prism 350, a reflective light modulation device 340, and a projection lens 360.

[0139] The projection display device 1001 of this embodiment further includes: a diffuser plate 310a disposed between the rear-side transflection lens 202 and the light path conversion mirror 330; and a second transflection optical system 320, which is composed of a front-side transflection lens 321 and a rear-side transflection lens 322 disposed across the light path conversion mirror 330.

[0140] In Embodiment 1, the first transpiling lens 200 magnifies and transpiles the rectangular illumination area IM1 onto the screen of the reflective light modulator 340, while in this embodiment, the first transpiling lens 200 (first transpiling optical system) forms a secondary transpiled image IM2 at the position of the diffuser plate 310a. Then, the secondary transpiled image IM2 scattered by the diffuser plate 310a is magnified and transpiled onto the screen of the reflective light modulator 340 as a tertiary transpiled image IM3 by the second transpiling optical system 320 (second transpiling optical system). The size of each image is typically set as follows.

[0141] IM1:IM2:IM3 = 1:2:6

[0142] According to this embodiment with such a structure, the F-value of the illumination light illuminating the reflective light modulator 340 is easily controlled.

[0143] In addition, Figure 10 In this design, the diffuser plate 310a is fixed in a fixed position, but it can also be configured such that the irradiation position of the laser on the diffuser plate moves over time, for example, by rotating the diffuser plate or making it reciprocate linearly. According to this method, flickering of the illumination light caused by the laser can be suppressed.

[0144] According to this embodiment, in the field of projection image display devices that modulate and project lasers based on image signals, a small, easy-to-drive and control device with high light utilization efficiency can be realized.

[0145] [Implementation Method 3]

[0146] In Embodiments 1 and 2, the light source includes an integrator illumination system INT, which is used to superimpose multiple laser beams emitted from the laser module LM to form a rectangular illumination area. This embodiment also shares the commonality of including an integrator illumination system INT for forming the rectangular illumination area. However, the integrator illumination system in Embodiments 1 and 2 includes a microlens array, while the integrator illumination system in this embodiment includes a rod-shaped optical integrator. Descriptions common to Embodiment 1 are simplified or omitted.

[0147] Figure 11 This diagram illustrates the light source according to Embodiment 3, specifically the integrator illumination system equipped with a rod-shaped optical integrator. The integrator illumination system of this embodiment includes a laser module LM, a condenser lens 401, a diffuser 402, a light rod 403, and a relay lens 406, thereby forming a rectangular illumination area IM1. Regarding the semiconductor laser, the light-emitting portion 12 of the semiconductor laser, the collimating lens 102, etc., included in the laser module LM, since they are similar to those in the reference... Figure 2 (a)~ Figure 4 The same applies to Implementation 1 as described in (b), so the description is omitted here.

[0148] The laser beams emitted from each semiconductor laser in the laser module LM are made approximately parallel by the collimating lens 102, with the divergence angle as already explained. The approximately collimated laser beams output from the laser module LM are focused onto the incident surface INP of the light bar 403 by the condenser lens 401. In this figure, the condenser lens 401 is represented by a single convex lens, but it can also be composed of multiple lenses for purposes such as suppressing aberrations.

[0149] A diffuser 402 is disposed near the incident surface INP of the light rod 403. The laser beam, diffused by the diffuser 402, is incident on the light rod 403 from the incident surface INP. Since the beam output from the laser module LM has a better divergence angle along the shorter side of the rectangle than along the longer side, the light capture loss on the incident surface INP of the light rod 403 can be suppressed, thereby improving utilization efficiency. The light incident on the light rod 403 undergoes repeated total internal reflection on the side and exits from the exit surface EXP. By appropriately setting the diffusion capability (diffusion angle) of the diffuser 402 and the length of the light rod 403, the illuminance distribution on the exit surface EXP can be made uniform.

[0150] By transferring the image emitted from the exit surface EXP of the light bar 403 using the relay lens 406, a rectangular illumination area IM1 with high illuminance uniformity can be obtained. By appropriately setting the transfer magnification of the relay lens, an illumination area IM1 of the desired size, either reduced, equal in size, or enlarged, can be obtained. Furthermore, in Figure 11 In this example, the relay lens 406 is composed of two lenses: a front convex lens 406a and a rear convex lens 406b. However, the structure of the relay lens 406 is not limited to this example.

[0151] Figure 12 (a) is a diagram showing the light source 400 including the integrator illumination system INT in the direction of the short side (X direction) of the light-emitting part 12 of the semiconductor laser, which is observable. Figure 12 (b) is a diagram showing the light source 400 including the integrator illumination system INT in the direction of the long side (Y direction) of the light-emitting part 12 of the semiconductor laser, which is observable.

[0152] The light bar 403 can be any optical device capable of causing total internal reflection of incident light at its side; for example, it can use... Figure 13 The optical device shown in (a) or Figure 13 The optical device shown in (b). Preferably, the light bar 403 is configured such that the shape of the incident surface INP, the shape of the exit surface EXP, and the cross-sectional shape of the light bar portion are the same.

[0153] Figure 13 The light bar 403 shown in (a) is, for example, a solid quadrangular prism made of an optical material such as optical glass or a light-transmitting resin, with the incident surface INP and the exit surface EXP, which are rectangular with a long side of H0 and a short side of V0. Preferably, the incident surface INP and the exit surface EXP are pre-coated with an anti-reflective film (AR coating).

[0154] in addition, Figure 13 The light bar 403 shown in (b) is a hollow quadrangular prism, i.e., a cylindrical device, with a reflective surface formed on the inner surface of the cylinder, for example, made of aluminum. The incident surface INP and the exit surface EXP, which serve as the opening of the cylinder, are rectangles with a long side of H0 and a short side of V0. For example, by depositing a reflective film such as an aluminum film on a glass or metal plate substrate and then bonding the substrates together to assemble them into a cylindrical shape, it is possible to manufacture it at a relatively low cost.

[0155] The incident surface INP and exit surface EXP of the light bar 403 are, as described above, rectangular with a long side H0 and a short side V0. Through the relay lens 406, they form... Figure 12(c) shows a rectangular illumination region IM1 with a long side of H1 and a short side of V1. The long side of the rectangular illumination region IM1 corresponds to the parallel direction (the slow axis direction of the semiconductor laser), and the short side corresponds to the orthogonal direction (the fast axis direction of the semiconductor laser). For example, if the shape of the incident surface INP and the exit surface EXP of the light bar 403 is set to be a rectangle with a short side V0 of 0.33 mm and a long side H0 of 1.67 mm, and the magnification of the relay lens 406 is set to 1.2x, then a rectangular illumination region IM1 with a V1 of about 0.4 mm and an H1 of about 2 mm can be obtained.

[0156] Figure 14 The figure shows a general structure of the optical system of the projection display device 1002 according to Embodiment 3. For ease of explanation, the mechanical structure, housing, electrical wiring, etc., used for mounting the optical components are omitted in this figure. This embodiment will refer to... Figure 1 In the projection display device 1000 described in Embodiment 1, the B light source 100B, G light source 100G, and R light source 100R are replaced with B light source 400B, G light source 400G, and R light source 400R using a rod-shaped optical integrator. Details common to the projection display device 1000 in Embodiment 1 are omitted from the description.

[0157] Figure 15 It is the same as in implementation method 1 Figure 8 Figure (a) shows the positional relationship between the deflector and the rectangular illumination area IM1. The coordinate system is shown with reference to light source B 400B.

[0158] The projection display device of this embodiment is provided with an illumination component for each different color of light and has a light combining unit. The illumination component includes multiple semiconductor lasers, collimating lenses, an integrator illumination system and a deflection device. The light combining unit combines the illumination light output by the illumination components of different colors of light. The rectangular illumination area output by each of the illumination components of different colors of light is deflected and scanned in a non-overlapping manner and magnified and projected onto a reflective light modulation device.

[0159] According to this embodiment, in the field of projection image display devices that modulate and project lasers based on image signals, a small, easy-to-drive and control device with high light utilization efficiency can be realized.

[0160] [Implementation Method 4]

[0161] Figure 16 The figure shows a general structure of the optical system of the projection display device 1003 according to Embodiment 4. For ease of explanation, the mechanical structure, body, electrical wiring, etc., used to mount the optical components are omitted in this figure. This embodiment will refer to Figure 10The B light source 100B, G light source 100G, and R light source 100R of the projection display device 1001 described in Embodiment 2 are replaced with the B light source 400B, G light source 400G, and R light source 400R using a rod-shaped optical integrator as described in Embodiment 3. Details common to the projection display device 1001 in Embodiment 2 are omitted from the description.

[0162] Similar to Embodiment 2, in this embodiment, the first transpiling lens 200 (first transpiling optical system) forms a secondary transpiled image IM2 at the position of the diffuser plate 310a. Then, the secondary transpiled image IM2 scattered by the diffuser plate 310a is magnified and transpiled onto the screen of the reflective light modulator 340 as a tertiary transpiled image IM3 by the second transpiling optical system 320 (second transpiling optical system). The size of each image is typically set as follows.

[0163] IM1:IM2:IM3 = 1:2:6

[0164] According to this embodiment with such a structure, the F-value of the illumination light illuminating the reflective light modulator 340 is easily controlled.

[0165] In addition, Figure 16 In this design, the diffuser plate 310a is fixed in a fixed position, but it can also be configured such that the irradiation position of the laser on the diffuser plate moves over time, for example, by rotating the diffuser plate or making it reciprocate linearly. According to this method, flickering of the illumination light caused by the laser can be suppressed.

[0166] According to this embodiment, in the field of projection image display devices that modulate and project lasers based on image signals, a small, easy-to-drive and control device with high light utilization efficiency can be realized.

[0167] [Other Implementation Methods]

[0168] Furthermore, the present invention is not limited to the embodiments described above, and various modifications can be made within the technical concept of the present invention.

[0169] For example, in an integrator lighting system INT, a diffractive diffuser (so-called top-cap device) can be configured to replace the paired microlens arrays 103 and 104. If the top-cap devices have different diffusion angles in the X and Y directions, it is not necessary to provide two; one device can be used instead.

[0170] Alternatively, instead of the microlens arrays 103 and 104 formed by two-dimensionally arranging microlenses with spherical shapes, arrays of striped microlenses (cylindrical lenses) in the X direction and arrays of striped microlenses (cylindrical lenses) in the Y direction can be set independently. With such a structure, the focal length and array spacing can be set independently of the stripe spacing, thus suppressing capture instability caused by insufficient array division and making it easier to generate a finer and more uniform rectangular light spot.

[0171] In addition, regarding the light rod 403, an example is given of a structure in which the shape of the incident surface INP, the shape of the exit surface EXP, and the cross-sectional shape of the light rod portion are the same. However, a light rod with a different shape of the incident surface INP and the exit surface EXP, such as a so-called conical light rod, can also be used.

[0172] Furthermore, in embodiments 1 to 4, the transpilation optical system used for image transpilation, namely the first transpilation lens 200 (first transpilation optical system), the second transpilation optical system 320, and the relay lens 406, is preferably configured with both sides telecentric, but other configurations are also possible. One or more of these transpilation optical systems may be, for example, a so-called deformable optical system (deformable lens) with different optical properties on two cross sections around the optical axis.

[0173] Figure 17 of (a), Figure 17 (b) is an example of a distorting optical system used in the relay lens 406 in Embodiment 3 or Embodiment 4. The figures are viewed from mutually orthogonal directions. Although the structure projects an image with a magnification of 2x through a combination of the front convex lens 406a and the rear convex lens 406b, by adding cylindrical lenses (concave lens 407a and convex lens 407b) with curvature applied only in the X direction to make them afocal, a distorting optical system is constructed, thereby allowing the magnification to be changed in only one direction. In this example, the image emitted from the exit surface EXP of the light bar 403 is projected into a rectangular illumination area IM1 with an equal magnification in the X direction and a magnification of 2x in the Y direction. Of course, this is just an example; the magnification or reduction can be arbitrarily set.

[0174] In this way, if the first transpiling lens 200 (first transpiling optical system), the second transpiling optical system 320, the relay lens 406 and other transpiling optical systems are set as deformable optical systems, the magnification in only one direction can be reduced or magnified. Therefore, the aspect ratio of the NA and the transpiled image can be adjusted, thereby further improving the light utilization efficiency.

Claims

1. A projection display device, characterized in that, have: Multiple semiconductor lasers; A collimating lens is used to collimate the multiple laser beams output from the plurality of semiconductor lasers; An integrator illumination system superimposes multiple laser beams collimated by the collimating lens to form a rectangular illumination area. The deflection device is positioned closer to the collimating lens than the location where the rectangular illumination area is formed by the integrator illumination system; The transpilation optical system magnifies and transpiles the rectangular illumination area, which is deflected and scanned by the deflection device, onto a reflective light modulation device. as well as The projection lens projects the image light output from the reflective light modulation device. The deflection device is rotatable about a rotation axis and has an optical surface arranged along a circumference centered on the rotation axis. The optical surface is configured such that its tilt angle relative to the rotation axis varies along the circumference. The tilt angle is configured such that, while the optical surface is continuously rotated at a certain speed, the laser beam is recursively deflected in a certain direction at a certain deflection speed.

2. The projection display device according to claim 1, characterized in that, The plurality of semiconductor lasers are configured such that the slow axis direction is consistent with the fast axis direction. The long side of the rectangular illumination region is oriented along the slow axis of the semiconductor laser. The short side of the rectangular illumination region is oriented along the fast axis of the semiconductor laser. The deflection device deflects the laser beam along the short side of the rectangular illumination area.

3. The projection display device according to claim 1 or 2, characterized in that, The integrator illumination system comprises: a microlens array consisting of spherical microlenses arranged in a two-dimensional manner, a diffractive diffusion device, or a microlens array consisting of striped microlenses.

4. The projection display device according to claim 1 or 2, characterized in that, The integrator illumination system includes: a light bar; a focusing lens that focuses multiple laser beams collimated by the collimating lens onto the light bar; a diffuser disposed near the incident surface of the light bar; and a relay lens that transfers the image of the exit surface of the light bar.

5. The projection display device according to claim 4, characterized in that, The light bar is a prism made of optical material or a hollow cylinder with a reflective inner surface.

6. The projection display device according to claim 1 or 2, characterized in that, Either the integrator illumination system or the transillumination optics system includes a deformable lens.

7. The projection display device according to claim 1 or 2, characterized in that, The mapping optical system includes: The first transfer optical system magnifies and transfers the rectangular illumination area onto the diffuser plate; as well as The second transillumination optical system transilluminates and transilluminates the rectangular illumination area that has been magnified and transilluminated onto the diffuser plate by the first transillumination optical system onto the reflective light modulator.

8. The projection display device according to claim 1 or 2, characterized in that, An illumination assembly is provided for each different color of light. The illumination assembly includes the plurality of semiconductor lasers, the collimating lens, the integrator illumination system, and the deflection device. The projection display device includes a light combining unit that combines the illumination light output from the illumination components of different colors. The rectangular illumination areas output by each of the illumination components of different colors of light are deflected and scanned in a non-overlapping manner and magnified and transferred onto the reflective light modulator.

Images