A projection display device

Abstract

The present invention relates to a projection display device comprising: a first condensing lens for condensing collimated laser beams of a plurality of semiconductor lasers of a first wavelength; a second condensing lens for condensing collimated laser beams of a plurality of semiconductor lasers of a second wavelength; a light diffusion device comprising a light diffusion surface, the area of ​​which is larger than each of the irradiation spots of the laser beams of the first wavelength condensed by the first condensing lens and the irradiation spots of the laser beams of the second wavelength condensed by the second condensing lens; a first integrator illumination system for superimposing the laser beams of the first wavelength diffused by the light diffusion surface to form a rectangular irradiation area of ​​the first wavelength; and a second integrator illumination system for superimposing the laser beams of the second wavelength diffused by the light diffusion surface to form a rectangular irradiation area of ​​the second wavelength.

Description

Technical Field

[0001] The present invention relates to a projection display device including a light source device. Background Art

[0002] Conventionally, there has been known a projection display device using laser light.

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

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

[0005] The projection display device described in Patent Document 1 includes an optical scanning unit that uses a polygonal mirror for horizontal scanning and a galvanometer mirror for vertical scanning. Since optical scanning is performed in both the horizontal and vertical directions, a large optical path space is required, resulting in a problem of large-scale device.

[0006] Therefore, in the field of projection-type image display devices that modulate laser light according to image signals and project the resulting image, there is a demand for a device that is compact, easy to drive and control, and has high light utilization efficiency. Summary of the Invention

[0007] One aspect of the present invention is a projection display device, characterized in that it comprises: a first collimating lens for collimating a plurality of laser beams output from a plurality of semiconductor lasers emitting light at a first wavelength; a first condensing lens for condensing the plurality of laser beams collimated by the first collimating lens; a second collimating lens for collimating a plurality of laser beams output from a plurality of semiconductor lasers emitting light at a second wavelength; a second condensing lens for condensing the plurality of laser beams collimated by the second collimating lens; a light diffuser having a light diffusing surface, the area of ​​the light diffusing surface being larger than each of an irradiation spot of the laser beam of the first wavelength condensed by the first condensing lens and an irradiation spot of the laser beam of the second wavelength condensed by the second condensing lens; and a first integrator illumination system for superimposing the laser beams of the first wavelength diffused by the light diffusing surface to form a The rectangular irradiation area of ​​the first wavelength is superimposed on the laser beam of the second wavelength diffused by the light diffusion surface; the second integrator illumination system is configured to form a rectangular irradiation area of ​​the second wavelength by superimposing the laser beam of the second wavelength diffused by the light diffusion surface; the first deflection unit is configured to be closer to the first integrator illumination system than the position where the rectangular irradiation area of ​​the first wavelength is formed by the first integrator illumination system; the second deflection unit is configured to be closer to the second integrator illumination system than the position where the rectangular irradiation area of ​​the second wavelength is formed by the second integrator illumination system; a projection optical system is configured to enlarge and project the rectangular irradiation area of ​​the first wavelength deflected and scanned by the first deflection unit and the rectangular irradiation area of ​​the second wavelength deflected and scanned by the second deflection unit onto a reflective light modulator; and a projection lens is configured to project the image light output by the reflective light modulator.

[0008] Another aspect of the present invention is a projection display device, characterized in that it comprises: a first collimating lens for collimating a plurality of laser beams output from a plurality of semiconductor lasers emitting light at a first wavelength; a second collimating lens for collimating a plurality of laser beams output from a plurality of semiconductor lasers emitting light at a second wavelength; a combining unit for superimposing and combining the plurality of laser beams collimated by the first collimating lens and the plurality of laser beams collimated by the second collimating lens; a first condensing lens for focusing the plurality of laser beams combined by the combining unit; a light diffuser having a light diffusion surface, the light diffusion surface having an area larger than the irradiation spot of the plurality of laser beams focused by the first condensing lens; a first integrator illumination system for superimposing the laser beams of the first wavelength among the plurality of laser beams diffused by the light diffusion surface to form a rectangular irradiation area of ​​the first wavelength; a second integrator illumination system for superimposing the laser beams of the second wavelength among the plurality of laser beams diffused by the light diffusion surface to form a rectangular irradiation area of ​​the second wavelength; and a first deflection unit disposed at a position larger than the rectangular irradiation area of ​​the first wavelength formed by the first integrator illumination system. a second deflection unit disposed closer to the second integrator illumination system than a position where the rectangular illumination area of ​​the second wavelength is formed by the second integrator illumination system; a relay optical system that magnifies and relays the rectangular illumination area of ​​the first wavelength deflected and scanned by the first deflection unit and the rectangular illumination area of ​​the second wavelength deflected and scanned by the second deflection unit onto a reflective light modulator; and a projection lens that projects image light output by the reflective light modulator. The first and second integrator illumination systems share a light rod, and a plurality of laser beams transmitted through the light diffusion surface are incident on the light rod. The first integrator illumination system includes a separator that separates the laser beam of the first wavelength from the plurality of laser beams emitted from the light rod; and a relay lens that relays an image of the exit surface of the light rod. The second integrator illumination system includes a separator that separates the laser beam of the second wavelength from the plurality of laser beams emitted from the light rod; and a relay lens that relays an image of the exit surface of the light rod.

[0009] According to the present invention, in the field of projection type image display devices that modulate laser light according to image signals and project the image, a device that is compact, easy to drive and control, and has high light utilization efficiency can be realized. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 This is a diagram showing a schematic configuration of an optical system of a projection display device according to Embodiment 1.

[0011] Figure 2(a) is a typical diagram showing a pairing of a semiconductor laser 11 and a collimating lens 102 included in the laser module LM; Figure 2 (b) is a typical diagram showing a laser module LM in which 4×2 pairs of semiconductor lasers 11 and collimating lenses 102 are arranged.

[0012] Figure 3 (a) is a diagram illustrating a near-field pattern of output light from the semiconductor laser 11; Figure 3 (b) is a diagram illustrating a far-field pattern of output light from the semiconductor laser 11 .

[0013] Figure 4 (a) is a diagram showing beam expansion for a parallel direction; Figure 4 (b) is a diagram showing the beam expansion for the orthogonal direction.

[0014] Figure 5 This is a diagram for explaining the integrator lighting system according to the first embodiment.

[0015] Figure 6 (a) is a diagram of the integrator lighting system INT according to the first embodiment as viewed from one direction; Figure 6 (b) is from Figure 6 (a) is a diagram showing the integrator illumination system INT according to the first embodiment as viewed from a direction perpendicular to the first embodiment; Figure 6 (c) is a diagram showing a rectangular irradiation area IM1.

[0016] Figure 7 (a) is a diagram showing a solid light bar used in an integrator illumination system; Figure 7 (b) is a diagram showing a hollow light rod used in the integrator illumination system.

[0017] Figure 8 (a) is a perspective view showing the appearance of an example of the deflector 210; Figure 8 (b) is a side view of the deflector 210.

[0018] Figure 9 (a) is a cross-sectional view for explaining the position and tilt angle of the reflecting surface of the deflector 210; Figure 9 (b) is a graph for explaining the position and tilt angle of the reflection surface of the deflector 210.

[0019] Figure 10 (a) is a diagram showing the positional relationship between the deflector 210 and the rectangular irradiation area IM1; Figure 10(b) is an enlarged view of the light beam irradiation position 214 of the reflecting surface; Figure 10 (c) is a diagram showing that the blue rectangular irradiation area IM1 is deflected and scanned in the DB direction.

[0020] Figure 11 (a) is a typical diagram for explaining the functions of the front-side transfer lens 201 and the rear-side transfer lens 202; Figure 11 (b) is a diagram showing the relationship between the screen of the reflective light modulation device 340 and the rectangular laser beam scanning range SA; Figure 11 (c) is a diagram showing how the screen of the reflective light modulation device 340 is irradiated with rectangular B light beam, G light beam, and R light beam, respectively, with the horizontal axis being the time axis.

[0021] Figure 12 (a) is a side view and a top view of the light diffuser 402 according to the embodiment; Figure 12 (b) is a side view and a top view of another light diffuser 402 according to the embodiment.

[0022] Figure 13 This is a diagram showing basic components of the integrator lighting system INT according to the second embodiment as viewed from one direction.

[0023] Figure 14 This is a diagram showing a schematic configuration of an optical system of a projection display device according to a third embodiment.

[0024] Figure 15 This is a diagram showing a schematic configuration of an optical system of a projection display device according to a fourth embodiment.

[0025] Figure 16 (a) is a plan view showing the appearance of an example of the deflector 210a; Figure 16 (b) is a side view of an example of the deflector 210a; Figure 16 (c) is a bottom view showing the appearance of an example of the deflector 210a.

[0026] Figure 17 (a) is a side view of a modified example of the deflector 210a; Figure 17 (b) is a side view of another modified example of the deflector 210a; Figure 17 (c) is a side view of yet another modified example of the deflector 210a.

[0027] Figure 18 This is a diagram showing a schematic configuration of an optical system of a projection display device according to a fifth embodiment.

[0028] Figure 19(a) is a perspective view showing the appearance of the laser module LM-BGR; Figure 19 (b) is a diagram illustrating the wavelengths of output light from semiconductor lasers of various colors.

[0029] Figure 20 This is a diagram showing a schematic configuration of an optical system of a projection display device according to a sixth embodiment.

[0030] Figure 21 This is a diagram showing a schematic configuration of an optical system of a projection display device according to a seventh embodiment.

[0031] Figure 22 This is a diagram showing a schematic configuration of an optical system of a projection display device according to the eighth embodiment.

[0032] Figure 23 This is a diagram showing a schematic configuration of an optical system of a projection display device according to a ninth embodiment.

[0033] Figure 24 This is a diagram showing a schematic configuration of an optical system of a projection display device according to a tenth embodiment.

[0034] Figure 25 This is a diagram showing a schematic configuration of an optical system of a projection display device according to a modified example of the tenth embodiment.

[0035] Description of Reference Numerals

[0036] 11…Semiconductor laser

[0037] 12…Light-emitting part

[0038] 102…Collimating lens

[0039] 190…projection screen

[0040] 201, 201B, 201G, 201R…front transfer lens

[0041] 202…Rear side transfer lens

[0042] 210…Deflector

[0043] 210B…B deflector

[0044] 210G...G deflector

[0045] Deflector for 210R...R

[0046] 211…matrix

[0047] 212…motor

[0048] 213…Reflective surface

[0049] 214…Beam irradiation position

[0050] 225…Photosynthesis Department

[0051] 221a, 221b, 223, 224, 224a, 224b, 231 to 237… dichroic mirrors

[0052] 310a…Light diffuser

[0053] 320…Second projection optical system

[0054] 321…Front-side transfer lens

[0055] 322…Rear side transfer lens

[0056] 330, 331a~330c, 331e~330i…optical path conversion mirror

[0057] 340…Reflective light modulation device

[0058] 350…TIR prism

[0059] 360…projection lens

[0060] 401…condenser lens

[0061] 402, 402a, 402b…light diffuser

[0062] 403, 403GB, 403R…Rod-type optical integrator

[0063] 406…Relay lens

[0064] 406a…front convex lens

[0065] 406b… rear convex lens

[0066] 1004-1009…Projection display device

[0067] DIF, DIF1, DIF2…light diffusion surface

[0068] IM1…Rectangular irradiation area

[0069] IM2…Secondary Image Transfer

[0070] IM3…Third Image Transfer

[0071] INT…Integrator Lighting System

[0072] LM, LM-B, LM-G, LM-R... laser modules

[0073] SUB…Translucent substrate DETAILED DESCRIPTION

[0074] Hereinafter, a projection display device as an embodiment of the present invention will be described with reference to the accompanying drawings.

[0075] The embodiments shown below are for illustrative purposes only. For example, the technical solutions in some details may be appropriately modified by those skilled in the art without departing from the spirit of the present invention. Furthermore, in the drawings referenced in the following embodiments and descriptions, elements denoted by the same reference numerals have the same functions unless otherwise specified. Furthermore, the optical components in the drawings are typically shown, so the actual shapes and structures may not necessarily be faithfully illustrated. For example, even if a single lens is depicted in a drawing, it may be composed of multiple lenses unless otherwise specified.

[0076] In the following description, for example, when the term "positive X-direction" is used, it refers to the same direction as the direction indicated by the X-axis arrow in the coordinate system shown in the figure, and when the term "negative X-direction" is used, it refers to the direction 180 degrees opposite to the direction indicated by the X-axis arrow in the coordinate system shown in the figure. Furthermore, when the term "X-direction" is used alone, it refers to the direction parallel to the X-axis, regardless of whether it is the same direction as the X-axis arrow in the figure. The same applies to directions other than X.

[0077] In the following description, red is sometimes referred to as “R,” green as “G,” and blue as “B.” Thus, for example, R light and red light, G light source and green light source, and B laser and blue laser are synonymous.

[0078] [Implementation Method 1]

[0079] Figure 1 This figure shows a schematic configuration of an optical system of a projection display device according to Embodiment 1. For ease of explanation, the figure omits the mechanical structure for installing optical components, a housing, electrical wiring, and the like.

[0080] [Overall structure]

[0081] The projection display device 1004 includes a B light source including a laser module LM-B, a G light source including a laser module LM-G, an R light source including a laser module LM-R, a B deflector 210B, a G deflector 210G, an R deflector 210R, a light combining unit including a dichroic mirror 224, an optical path conversion mirror 330, a TIR prism 350, a reflective light modulation device 340, and a projection lens 360. Optionally, the projection display device 1004 may include a projection screen 190.

[0082] The light sources of each color (B light source, G light source, R light source) will be described in detail later.

[0083] The B deflector 210B deflects the B light emitted by the B light source toward the DB direction. Similarly, the G deflector 210G deflects the G light emitted by the G light source toward the DG direction, and the R deflector 210R deflects the R light emitted by the R light source toward the DR direction. The deflectors will be described in detail later. Alternatively, the R deflector 210R may be referred to as the first deflection unit, the B deflector 210B as the second deflection unit, and the G deflector 210G as the third deflection unit.

[0084] The dichroic mirror 224, which constitutes the light combining unit, has optical properties that transmit R light and reflect B light and G light. The optical components are arranged so that the optical axis centers of the front transfer lens 201B for B light, the front transfer lens 201G for G light, and the front transfer lens 201R for R light overlap on the dichroic mirror 224.

[0085] The light combining unit unifies the travel directions of the B light (dashed line), G light (solid line), and R light (single-dot chain line) in the positive Z direction. However, these lights are combined so that they do not overlap at any time. This is because the deflection scanning timing (deflection phase) of the B deflector 210B, G deflector 210G, and R deflector 210R is controlled so that the B light, G light, and R light do not overlap on the screen of the reflective light modulator 340. The scanning method will be described in detail later.

[0086] The B light, G light, and R light emitted from the light combining unit (dichroic mirror 224 ) are redirected to the positive X direction by the optical path conversion mirror 330 and enter the TIR prism 350 .

[0087] The TIR prism 350 is, for example, a total internal reflection prism formed by combining two prisms. It causes the illumination light (B light, G light, and R light) to be totally reflected at the air gap surface, and then enter the reflective light modulator 340 at a predetermined angle. As described above, the B light, G light, and R light each illuminate a portion of the screen of the reflective light modulator 340 without overlapping.

[0088] The reflective light modulator 340 uses, for example, a digital micromirror device (DMD) in which micromirrors are arranged in an array. The micromirrors corresponding to each display pixel are driven according to the brightness level of the image signal, causing their reflection directions to be altered through pulse width modulation. However, other types of reflective light modulators, such as reflective liquid crystal devices, may also be used.

[0089] Pixels in the screen area illuminated by B light are driven based on the brightness level of the B component of the image signal, reflecting the B image light at a predetermined angle toward the TIR prism 350. Similarly, pixels in the screen area illuminated by G light are driven based on the brightness level of the G component of the image signal, reflecting the G image light at a predetermined angle toward the TIR prism 350. Furthermore, pixels in the screen area illuminated by R light are driven based on the brightness level of the R component of the image signal, reflecting the R image light at a predetermined angle toward the TIR prism 350. In this way, the modulation operation of the reflective light modulator is synchronized with the deflection scanning of the B deflector 210B, the G deflector 210G, and the R deflector 210R.

[0090] The image light (B image light, G image light, R image light) passes through TIR prism 350 and is guided to projection lens 360 to be projected as a color image. Projection lens 360 is composed of a single lens or multiple lenses and may have automatic focus adjustment and zoom functions.

[0091] The projection screen 190 is used when forming a rear projection display device. In addition, although it is often provided in the case of a front projection, it is not necessarily required to be provided when the user projects onto an arbitrary wall surface or the like.

[0092] [light source]

[0093] The following describes the B, G, and R light sources. The B light source comprises a laser module LM-B, the G light source comprises a laser module LM-G, and the R light source comprises a laser module LM-R. The laser module LM-B includes a semiconductor laser that emits B light and a collimating lens, the laser module LM-G includes a semiconductor laser that emits G light and a collimating lens, and the laser module LM-R includes a semiconductor laser that emits R light and a collimating lens. Aside from the wavelength of the semiconductor laser, the basic structures of the light sources of each color are similar. Therefore, in the following text, they are sometimes not distinguished by light color, but are described as light sources.

[0094] (Laser Module)

[0095] Each of the B light source, the G light source, and the R light source includes a laser module LM in which pairs of semiconductor lasers and collimating lenses are arranged in a one-dimensional or two-dimensional array.

[0096] Figure 2 (a) is a typical diagram showing a pairing of a semiconductor laser and a collimating lens included in the laser module LM. 11 is a semiconductor laser, and 12 is a light emitting portion of the semiconductor laser 11. Figure 2 In (a), Figure 1 The direction of the laser module LM-B is used as a reference, so that the Z axis direction is relative to Figure 1The XYZ coordinate system is reversed 180° to display the XYZ coordinate system. Figure 2 In (a), the diagram shows that the longitudinal direction H of the light emitting portion 12 is parallel to the Y direction, and the traveling direction of light emitted from the light emitting portion 12 is parallel to the Z direction.

[0097] The longitudinal direction H of the light emitting portion 12 is typically the direction in which the active layer sandwiched between the P-type cladding layer and the N-type cladding layer on the side surface of the semiconductor chip constituting the semiconductor laser 11 extends. Figure 2 As shown in (a), in the following description, the direction parallel to the long side direction H of the light emitting portion 12 of the semiconductor laser 11 may be referred to as the "parallel direction" or "slow axis", and the direction perpendicular to the long side direction of the light emitting portion 12 may be referred to as the "perpendicular direction" or "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).

[0098] It is known that the angular characteristics of the output light of the semiconductor laser 11 vary depending on the emission direction. Figure 3 (a) shows the near-field pattern of the output light. Figure 3 (b) illustrates the far-field pattern of the output light.

[0099] like Figure 3 As shown in (a), in the near-field pattern, it can be seen that this is a beam profile that reflects the shape of the light-emitting portion (long side, short side). On the other hand, as the beam travels, Figure 3 As shown in the far-field pattern of (b), the light beam gradually expands. That is, if viewed from a parallel direction, it can be seen that the light beam emitted from the semiconductor laser 11 has a small expansion and travels in a narrow angle range with a uniform intensity distribution. On the other hand, if viewed from an orthogonal direction, it can be seen that the light beam emitted from the semiconductor laser 11 has an intensity distribution in a mountain shape (Gaussian), and as it travels, it expands in an angular range wider than the parallel direction. This is because the active layer of the semiconductor laser has a small thickness in the orthogonal direction, so it is greatly affected by diffraction when emitted. The parallel direction with a small expansion seen in the far-field pattern can also be called the slow axis, and the orthogonal direction with a large expansion can be called the fast axis.

[0100] In this embodiment, if 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 portion 12 having a length Hy1 in the longitudinal direction is collimated by the collimating lens 102, forming a beam having an elliptical cross-section and traveling in the Z direction. In addition, the major axis of the elliptical shape is parallel to the X direction, and the minor axis is parallel to the Y direction.

[0101] Even if the light beam passes through the collimating lens 102, it will not be completely parallel to the optical axis (Z direction), and the light beam expansion mode is different in the parallel direction (long side direction of the light emitting part) and the orthogonal direction (short side direction of the light emitting part). Figure 4 (a) and Figure 4 (b) of FIG. 1 illustrates the difference in the way the light beam spreads after passing through the collimating lens 102. Figure 4 (a) shows the expansion in the parallel direction, Figure 4 (b) shows the expansion for the orthogonal direction.

[0102] like Figure 4 As shown in (a), if viewed from the parallel direction, the top of the beam intensity is flat, but as it advances in the Z direction, the beam diameter expands, so it cannot be said that the divergence angle is good. Figure 4 As shown in (b), when viewed from the orthogonal direction, it can be seen that even if the distance from the collimating lens 102 changes, the changes in the beam intensity distribution and beam diameter are very small. In other words, the laser beam after passing through the collimating lens 102 is more parallel in the orthogonal direction (the fast axis of the semiconductor laser) than in the parallel direction (the slow axis of the semiconductor laser), and the divergence angle is better.

[0103] As will be described later, the present invention utilizes the property of the light beam output from the light source having a superior divergence angle in the orthogonal direction (the direction of the short side of the rectangle) (high beam parallelism) to deflect and scan the beam in the orthogonal direction to illuminate the light modulator. This is because deflecting and scanning the beam in the direction with the superior divergence angle is beneficial for preventing overlap of the illumination areas of the various colors B, G, and R on the screen of the light modulator.

[0104] The light sources of each color include a laser module LM. The laser module LM includes a pair of a plurality of semiconductor lasers and a collimating lens 102 (first collimating lens). Figure 2 (b) is a typical diagram showing a laser module LM in which 4×2 pairs of semiconductor lasers 11 and collimating lenses 102 are arranged. Figure 2 In (b), Figure 1 The direction of the laser module LM-B is used as a reference, so that the Z axis direction is relative to Figure 1 The XYZ coordinate system is flipped 180° to display the XYZ coordinate system.

[0105] In the laser module LM, a plurality of semiconductor lasers are configured to be arranged at equal intervals along the Y direction. In addition, all semiconductor lasers are configured in the direction along the Y direction with the long side direction of the light emitting portion 12. Although an example of a semiconductor laser using 4×2 devices is shown, the number of devices is not limited to this example. The laser module LM can also be configured to have a structure in which a plurality of semiconductor lasers are arranged in only one row or in three or more rows along the Y direction. Even for a light source having a device column of one or more than three rows of semiconductor lasers along the Y direction, the output light beam has a better divergence angle in the short side direction of the light emitting portion than in the long side direction.

[0106] (Integrator Illumination System / Optical Overlay Unit)

[0107] The light source of this embodiment includes an integrator illumination system INT for superimposing a plurality of laser beams emitted from the laser module LM to form a rectangular irradiation area. Figures 5 to 7 (b) of the drawings will now describe the integrator lighting system INT.

[0108] The laser beam emitted from each of the semiconductor lasers 11 included in the laser module LM becomes substantially parallel under the action of the collimating lens 102, and the divergence angle is as described above. Figure 6 In the rectangular irradiation area IM1 shown in FIG. 5 (c), the light source of this embodiment includes an integrator illumination system INT for superimposing the laser beams emitted from the respective semiconductor lasers.

[0109] Figure 5 This figure is used to illustrate the light source involved in Embodiment 1, that is, the integrator illumination system including a rod-shaped optical integrator. The integrator illumination system involved in this embodiment includes a laser module LM, a condenser lens 401, a light diffuser 402, a rod-shaped optical integrator 403, and a relay lens 406, and forms a rectangular irradiation area IM1. The semiconductor laser, the light emitting unit 12 of the semiconductor laser, the collimating lens 102, etc. included in the laser module LM are as described in reference. Figure 2 (a)~ Figure 4 As explained in (b) of Figure 5 In Figure 1 The direction of the laser module LM-B is used as a reference, so that the Z axis direction is relative to Figure 1 The XYZ coordinate system is reversed 180° to display the XYZ coordinate system. For the convenience of illustration, the light path folding back from the laser module LM to the rectangular irradiation area IM1 is omitted.

[0110] The laser beams emitted from each of the semiconductor lasers included in the laser module LM are substantially parallelized by the collimating lens 102, with the divergence angles being as previously described. The substantially collimated laser beams output from the laser module LM are focused by the focusing lens 401 onto the incident surface INP of the rod optical integrator 403. In this figure, the focusing lens 401 is shown as a single convex lens, but it can also be composed of multiple lenses to suppress aberrations, for example.

[0111] A light diffuser 402 is positioned near the incident surface INP of the rod-shaped optical integrator 403. The laser beam, diffused by the light diffuser 402, enters the rod-shaped optical integrator 403 from the incident surface INP. Because the light beam output from the laser module LM has a better divergence angle along the shorter sides of the rectangle than along the longer sides, light capture loss at the incident surface INP of the rod-shaped optical integrator 403 is suppressed, thereby improving light utilization efficiency. Light entering the rod-shaped optical integrator 403 undergoes repeated total internal reflection from the side surfaces before exiting from the exit surface EXP. By appropriately setting the diffusion capacity (diffusion angle) of the light diffuser 402 and the length of the rod-shaped optical integrator 403, the illumination distribution on the exit surface EXP can be made uniform.

[0112] In this embodiment, a single rotatable light diffuser 402 is used to diffuse the B laser light, the G laser light, and the R laser light. Figure 12 The left side of (a) shows a side view of the light diffuser 402. Figure 12 The right side of (a) shows a top view of a light diffuser 402. The light diffuser 402 includes a translucent substrate SUB provided with a light diffuser surface DIF, and a motor 412 that rotates the translucent substrate SUB about a rotation axis CX. The light diffuser surface DIF can be formed by having, for example, finely contoured surfaces on the principal surface of the translucent substrate SUB on which laser light is incident, on the principal surface on which laser light transmitted through the translucent substrate SUB is emitted, or on both surfaces.

[0113] When highly coherent light, such as laser light, is superimposed on an integrator optical system, it is necessary to consider not only the effects of geometric optics but also the effects of wave optics. Due to the effects of wave optics, the laser light incident on the rod-shaped optical integrator 403 may interfere with each other, resulting in light and dark patterns such as interference fringes or speckles within the rectangular illumination area IM1. If a uniform, non-uniform light and dark pattern is generated within the rectangular illumination area IM1, the displayed image may suffer from visually noticeable degradation, making it unsuitable for use as illumination light for display.

[0114] Therefore, the light diffuser 402 used in this embodiment includes a light diffuser surface DIF having an area larger than the laser beam spot (irradiation position), and includes a movement mechanism (motor 412) for moving the light diffuser surface DIF. This allows the location of the light diffuser surface DIF irradiated by the laser beam to be dynamically changed. In other words, the light diffuser 402 can be said to be an optical device having a dynamic light diffuser surface.

[0115] In this embodiment, the light diffusion device having a dynamic light diffusion surface is arranged between the laser light source and the incident surface of the integrator optical system. Figure 5 As shown, the light diffuser 402 is positioned between the laser module LM and the incident surface INP of the rod-shaped optical integrator 403. With this arrangement, the portion of the laser beam irradiating the light diffuser surface DIF is moved at an appropriate speed, thereby reducing the temporal and spatial coherence of the light incident on the integrator optical system. This prevents interference fringes and other light-dark patterns from forming when the light beams are superimposed in the integrator optical system. By moving the light diffuser surface at an appropriate speed, the effective illumination distribution within the rectangular illumination area IM1 can be made extremely uniform, consistent with human visual characteristics.

[0116] In this embodiment, the circular light diffuser is rotated to move the laser irradiation position relative to the plate along its circumference. However, the structure of the light diffuser device with a dynamic light diffusion surface is not limited to this. For example, a drive mechanism such as a piezoelectric actuator can be used to reciprocate the light diffuser in a linear or curved motion, thereby dynamically changing the laser irradiation position on the light diffuser over time. This approach can also reduce the coherence of the laser light incident on the integrator optical system, thereby achieving an extremely uniform effective illumination distribution within the rectangular irradiation area IM1 in accordance with human visual characteristics.

[0117] In this embodiment, if Figure 12 As shown in (a), R light is irradiated at the position indicated as SPOT1, and B light and G light are irradiated at the position indicated as SPOT2. That is, the three colors of laser light, B, G, and R, are diffused by a single light diffuser 402, which is rotated by a single motor 412. According to this embodiment, the number of parts can be reduced compared to the case of providing a motor and light diffuser for each color, thereby reducing the cost of the projection display device.

[0118] In addition, the light diffuser 402 rotated by the single motor 412 is not limited to Figure 12 Regarding an example of the light diffuser 402 of another embodiment, Figure 12The left side of (b) shows a side view, Figure 12 In this example, an annular light diffusing surface DIF1 is provided on the inner circumference (the side close to the rotation axis CX) of the disk-shaped translucent substrate SUB, and an annular light diffusing surface DIF2 is provided on the outer side thereof.

[0119] Generally speaking, the divergence angle of R-light semiconductor lasers is often worse than that of B-light or G-light semiconductor lasers. In addition, since the output power of each single device of R-light semiconductor lasers is smaller than that of B-light or G-light semiconductor lasers, more devices need to be arranged, and the NA of the light source may become larger. Figure 12 In the example (b), R light is irradiated onto the position indicated as SPOT1 on the light diffusing surface DIF1, and B light and G light are irradiated onto the position indicated as SPOT2 on the light diffusing surface DIF2. This allows the diffusion characteristics of the light diffusing surface DIF1 and the light diffusing surface DIF2 to differ according to the output characteristics of the semiconductor laser. For example, by configuring the light diffusing element 402 so that the diffusion capability of the light diffusing surface DIF1 is smaller than that of the light diffusing surface DIF2, the color balance of the illumination light illuminating the reflective light modulating element 340 can be improved. Alternatively, the light diffusing surface DIF1 may be referred to as the first diffusion region, and the light diffusing surface DIF2 may be referred to as the second diffusion region.

[0120] return Figure 5 By using the relay lens 406 to relay the image emitted from the exit surface EXP of the rod-shaped optical integrator 403, a rectangular irradiation area IM1 with high illumination uniformity can be obtained. By appropriately setting the relay lens's relay magnification, the irradiation area IM1 of a desired size can be obtained, either reduced, equal, or enlarged. Figure 5 In FIG. 4 , the relay lens 406 is composed of two lenses: a front convex lens 406 a and a rear convex lens 406 b . However, the structure of the relay lens 406 is not limited to this example.

[0121] Figure 6 (a) is a diagram showing a light source including an integrator illumination system INT in the direction of the short side (X direction) in which the light emitting portion 12 of the semiconductor laser can be viewed. Figure 6 (b) is a diagram showing a light source including the integrator illumination system INT in the direction of the longitudinal direction (Y direction) in which the light emitting portion 12 of the semiconductor laser can be viewed.

[0122] Here, yes Figure 1 The specific structure of the light sources of various colors in the projection display device shown is Figure 5 、 Figure 6 (a) Figure 6The corresponding relationship between (b) is explained.

[0123] First, regarding light source B, Figure 1 The laser module LM-B and the rod-shaped optical integrator 403GB shown correspond to Figure 5 The laser module LM and the rod-shaped optical integrator 403 are shown in FIG. Figure 1 In the process, the blue laser output by the laser module LM-B moves in the negative Z direction, but in Figure 5 etc. is represented as moving in the positive Z direction. Figure 1 In the optical path of the B light, a dichroic mirror 221a is provided between the laser module LM-B and the focusing lens 401 (shared with G), but Figure 5 As described above, the dichroic mirror 221a has an optical characteristic of transmitting G light and reflecting B light. Figure 1 In the optical path of the B light, a dichroic mirror 221b is provided between the front convex lens 406a (shared with the G light) and the rear convex lens 406b, but Figure 5 The dichroic mirror 221b has an optical characteristic as a separation device that transmits G light and reflects B light. Figure 1 In the optical path of the B light, a B deflector 210B is arranged between the rear convex lens 406b and the irradiation area IM1, but Figure 5 etc. are omitted.

[0124] Next, regarding the G light source, Figure 1 The laser module LM-G and the rod-shaped optical integrator 403GB shown correspond to Figure 5 The laser module LM and the rod-shaped optical integrator 403 are shown in FIG. Figure 1 In the LM-G laser module, the green laser output moves in the positive X direction, but in Figure 5 etc. is represented as moving in the positive Z direction. Figure 1 In the optical path of the G light, a dichroic mirror 221a is provided between the laser module LM-G and the focusing lens 401 (shared with B), but Figure 5 The dichroic mirror 221a has the optical property of transmitting G light and reflecting B light. Figure 1 In the optical path of the G light, a dichroic mirror 221b is provided between the front convex lens 406a (shared with B) and the rear convex lens 406b, but Figure 5 The dichroic mirror 221b has the optical property of transmitting the G light and reflecting the B light. Figure 1 In the optical path of the G light, a G deflector 210G is arranged between the rear convex lens 406b and the irradiation area IM1, but Figure 5 etc. are omitted.

[0125] Next, regarding the R light source, Figure 1 The laser module LM-R and the rod-shaped optical integrator 403R shown correspond to Figure 5 The laser module LM and the rod-shaped optical integrator 403 are shown in FIG. Figure 1 In the process, the red laser output by the laser module LM-R moves in the positive X direction, but in Figure 5 etc. is represented as moving in the positive Z direction. Figure 1 In the optical path of the R light, an R deflector 210R is arranged between the rear convex lens 406b and the irradiation area IM1, but Figure 5 etc. are omitted.

[0126] return Figure 6 (a) Figure 6 (b) The rod-shaped optical integrator 403 can be any optical device that can cause the incident light to be totally reflected on its side. As the rod-shaped optical integrator 403, for example, Figure 7 The optical device shown in (a) or Figure 7 Preferably, the rod-shaped optical integrator 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 optical rod portion are the same.

[0127] Figure 7 The rod-shaped optical integrator 403 shown in (a) is a solid quadrangular prism-shaped device made of an optical material such as optical glass or a translucent resin. The incident surface INP and the exit surface EXP, which serve as end faces, are rectangular in shape with a long side H0 and a short side V0. Preferably, the incident surface INP and the exit surface EXP are provided with an anti-reflection coating (AR coating) in advance.

[0128] in addition, Figure 7 The rod-shaped optical integrator 403 shown in (b) is a hollow quadrangular prism, or cylindrical device, with a reflective surface made of, for example, aluminum, provided on the inner surface of the tube. The entrance surface INP and exit surface EXP, which form the opening of the tube, are rectangular with a long side H0 and a short side V0. For example, a reflective film such as aluminum is vapor-deposited onto a glass or metal plate-shaped substrate, and the substrates are then bonded together to form a cylindrical shape, making the device relatively inexpensive to manufacture.

[0129] The shapes of the incident surface INP and the exit surface EXP of the rod-shaped optical integrator 403 are rectangular with the long side H0 and the short side V0 as described above. Figure 6(c) shows a rectangular irradiation area IM1 with a long side of H1 and a short side of V1. The long side of the rectangular irradiation 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). For example, if the shape of the incident surface INP and the exit surface EXP of the rod-shaped optical integrator 403 is set to a rectangle with an X direction (short side V0) of 0.33 mm and a Y direction (long side H0) of 1.67 mm, and the magnification of the relay lens 406 is set to 1.2 times, a rectangular irradiation area IM1 with a V1 of 0.4 mm and an H1 of about 2 mm can be obtained.

[0130] (Deflector)

[0131] like Figure 1 As shown, deflectors (B deflector 210B, G deflector 210G, R deflector 210R) are arranged between the light sources (B light source, G light source, R light source) and the rectangular irradiation area IM1 irradiated by each.

[0132] The following describes the B deflector 210B, the G deflector 210G, and the R deflector 210R. Although these are deflection devices for deflecting and scanning laser beams of different colors, they have the same basic structure and are therefore sometimes described below as the deflector 210 without specifying the color.

[0133] Figure 8 (a) is a perspective view showing the appearance of an example of the deflector 210, Figure 8 (b) is a side view of the deflector 210.

[0134] The deflector 210 includes a rotatable disk-shaped base 211 and a motor 212 for rotating the base 211 around a rotation axis AX. A reflective surface 213, which is a strip-shaped optical surface, is provided along the circumference of the main surface of the disk-shaped base 211. Figure 8 As 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). The axis BX shown in the figure is parallel to the rotation axis AX and passes through the reflecting surface 213. The beam irradiation position 214 shows the position of the beam output from the light source 400 when it is reflected before reaching the rectangular irradiation area IM1.

[0135] The strip-shaped reflective surface 213 is twisted so that the angle relative to the axis BX (ie, the angle relative to the rotation axis AX) varies with position. Figure 9 (a) and Figure 9 (b) of the figure explains the angle of the reflecting surface. Figure 9 (a) and Figure 9In (b), the position of the reflecting surface is shown by Figure 8 The position is defined by the angular coordinates described in (a). The inclination angle of the reflecting surface is the inclination angle of the reflecting surface with respect to the main surface of the disk-shaped base 211 (ie, the surface perpendicular to the axis BX) as a reference.

[0136] like Figure 9 As shown in (b), the reflecting surface 213 is configured so that the inclination angle of the reflecting surface changes linearly with respect to the position of the reflecting surface. Figure 8 (a) Figure 9 As shown in (b), when the position of the reflecting surface is 0° (360°), the inclination angle of the reflecting surface is discontinuous, so for the sake of convenience, Figure 9 (a) shows the inclination angles when the position of the reflecting surface is 1° and 359°.

[0137] When the motor rotates the base 211 in the R direction, the reflective surface 213 also rotates around the rotation axis AX. Figure 8 At the beam irradiation position 214 shown in (a), the angular coordinates of the portion irradiated with the laser beam continuously change in the manner of 0°→90°→180°→360°(=0°)→90°...

[0138] Even if the reflecting surface rotates and the part of the reflecting surface irradiated by the laser beam changes, Figure 9 As shown in (a), the incident light beam always enters the reflecting surface 213 at an angle α relative to the axis BX. On the other hand, the inclination angle of the reflecting surface varies from -θ to +θ depending on the position of the reflecting surface. Therefore, as Figure 9 As shown in (a) of FIG. , the direction of the laser beam reflected by the reflecting surface 213 varies within an angular range of 4θ, from (α - 2×θ) to (α + 2×θ), relative to the axis BX. In other words, the tilt angle is configured so that when the optical surface (reflecting surface) is continuously rotated at a constant speed, the laser beam is recursively deflected in a constant direction at a constant deflection speed.

[0139] In other words, if Figure 8 As shown in (b), the deflector 210 can deflect and scan the outgoing light beam within the angle range from RD1 (relative to the axis BX (α-2×θ)) to RD2 (relative to the axis BX (α+2×θ)). Figure 8 When the reflecting surface 213 rotates continuously in the R direction of (a), the outgoing light beam is Figure 8 (b) RD1 is continuously deflected (scanned) toward RD2, and when it reaches RD2, it returns to RD1 instantly and deflects (scans) toward RD2 again. In addition, if the reflecting surface 213 is rotated in the opposite direction to R, the outgoing light beam will be Figure 8In (b), RD2 continuously deflects (scans) toward RD1, and upon reaching RD1, instantly returns to RD2, and deflects (scans) toward RD1 again.

[0140] In this manner, the deflector 210 can be used to recursively deflect and scan the laser beam in a predetermined direction at a constant speed using a simple driving method, simply by continuously rotating the rotating body at a constant speed. As will be described later, by controlling the motor 212 to rotate synchronously with the drive 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 across the screen of the reflective light modulator 340.

[0141] Furthermore, when implementing the present invention, a galvanometer mirror can be used instead of the rotating deflector 210. However, using a galvanometer mirror is expected to increase the size of the device, generate vibration, and increase costs. Therefore, using the rotating deflector 210 is preferred.

[0142] exist Figure 10 (a) shows the positional relationship between the deflector 210 and the rectangular irradiation area IM1 formed in front of the deflector 210. The coordinate system is shown with the B light source as the reference. Figure 10 (b) shows an enlarged view of the light beam irradiation position 214 of the reflecting surface. The light beam irradiation position 214 of the reflecting surface is arranged closer to the light source side than the rectangular irradiation area IM1 by a distance L. Figure 10 As shown in FIG. 5( c ), the blue rectangular irradiation area IM1 is deflected and scanned in the DB direction as the deflector 210 rotates.

[0143] In addition, the manufacturing method of the deflector 210 will be described in addition. The disc-shaped base 211 provided with the strip-shaped reflective surface 213 along the circumference can be manufactured at low cost by processing a metal base material using a stamping process, for example. Figure 9 As shown in the example of (a), near the reflective surface 213, there are portions protruding from the main surface of the base 211 and portions recessed. To ensure good rotational balance, it is preferable that the cross-section at any position have equal cross-sectional areas when viewed along a cross section passing through the rotation axis AX. Furthermore, to reduce wind noise, the maximum height protruding from the main surface of the base 211 and the maximum depth recessed from the main surface are preferably set to be no more than 3 / 4 of the average plate thickness. Specifically, the average plate thickness of the base 211 is preferably between 0.7 mm and 2 mm, and θ is preferably between 3° and 6°.

[0144] Using the deflector described above, as Figure 1As shown in FIG. 1 , rectangular irradiation areas IM1 of various colors formed by B, G, and R laser beams are deflected and scanned in the directions of DB, DG, and DR, respectively. Figure 1 The B deflector 210B, G deflector 210G, and R deflector 210R shown in FIG. Figure 8 The direction of the R direction shown in (a) is rotated in the opposite direction, and the rectangular irradiation area IM1 formed by the B light is rotated in the opposite direction. Figure 1 The deflection scan is performed in the direction of DB shown. G is deflected by the deflector 210G. Figure 8 The rectangular irradiation area IM1 formed by the G light is rotated in the opposite direction of the R direction shown in (a) and the rectangular irradiation area IM1 formed by the G light is rotated in the opposite direction of the R direction shown in (a) Figure 1 The deflection scanning is performed in the direction of DG shown in FIG. R is deflected by the deflector 210R. Figure 8 The R direction shown in (a) is rotated in the opposite direction, and the rectangular irradiation area IM1 formed by the R light is rotated in the opposite direction. Figure 1 Deflection scanning is performed in the direction of DR shown.

[0145] The light of each color deflected and scanned by the B deflector 210B, the G deflector 210G, and the R deflector 210R is guided to the dichroic mirror 224, which constitutes the light combining unit. The B light deflected and scanned by the B deflector 210B passes through the front-side transfer lens 201B, the dichroic mirror 223, and the optical path conversion mirror 330a, and is guided to the dichroic mirror 224, which constitutes the light combining unit. The dichroic mirror 223 has optical properties that transmit the B light and reflect the G light, and the optical path conversion mirror 330a has optical properties that reflect both the B light and the G light. The G light deflected and scanned by the G deflector 210G passes through the front-side transfer lens 201G, the dichroic mirror 223, and the optical path conversion mirror 330a, and is guided to the dichroic mirror 224, which constitutes the light combining unit. The R light deflected and scanned by the R deflector 210R passes through the front-side relay lens 201R and is guided to the dichroic mirror 224 constituting the light combining unit.

[0146] (Photosynthesis Department)

[0147] As already described in the section "Overall Structure," the dichroic mirror 224 constituting the light combining unit has optical properties that transmit R light and reflect B and G light. The optical components are arranged so that the optical axis centers of the front transfer lens 201B for B light, the front transfer lens 201G for G light, and the front transfer lens 201R for R light overlap on the dichroic mirror 224. The light combining unit aligns the travel directions of B light (dashed line), G light (solid line), and R light (single-dot chain line) in the positive Z direction, i.e., toward the rear transfer lens 202.

[0148] (Transfer optical system)

[0149] The first transfer lens (first transfer optical system) is composed of a front transfer lens 201B, a front transfer lens 201G, and a front transfer lens 201R, each provided for each color, and a rear transfer lens 202, which is common to all colors. The rectangular irradiation area IM1 formed by the laser beams of each color is magnified and transferred into a rectangular secondary transfer image IM2. Both the front transfer lens 201 and the rear transfer lens 202 are convex lenses with positive refractive power. The optical path length of the first transfer optical system, that is, the distance from the rectangular irradiation area IM1 to the rectangular secondary transfer image IM2, can be configured to be equal for each color.

[0150] Figure 11 (a) is a typical diagram for explaining the functions of the front side transfer lens 201 and the rear side transfer lens 202. As shown in the figure, the rectangular irradiation area IM1 is enlarged and transferred into a rectangular secondary transfer image IM2. Figure 1 As shown, the formation position of the rectangular secondary transferred image IM2 is set at the position of the light diffusion plate 310a.

[0151] The secondary transferred image IM2 diffused by the light diffuser 310a is then magnified and transferred as the tertiary transferred image IM3 by the second transfer optical system 320 onto the screen of the reflective light modulator 340. The second transfer optical system 320 is composed of a front transfer lens 321 and a rear transfer lens 322, which are arranged with an optical path conversion mirror 330 interposed therebetween. The sizes of the transferred images are typically set to the following relationship.

[0152] IM1:IM2:IM3=1:2:6

[0153] According to the present embodiment having such a configuration, it is easy to control the F value of the illumination light for illuminating the reflective light modulation device 340 .

[0154] In addition, Figure 1 In the embodiment, the light diffuser 310a is fixed at a fixed position, but the laser irradiation position on the light diffuser may be moved over time by rotating or reciprocating the light diffuser. This embodiment can suppress flickering of the illumination light caused by the laser.

[0155] exist Figure 11(b) shows the relationship between the screen of the reflective light modulator 340 and the rectangular laser beam scanning area SA. If the screen size of the reflective light modulator 340 is H (horizontally) × V (vertically), the rectangular laser beam scanning area SA covers an area H' × V', which is larger than the screen size. Furthermore, the rectangular laser beam scanning area SA is magnified by the aforementioned projection magnification relative to the scanning area of ​​the rectangular irradiation area IM1 scanned by the deflector 210.

[0156] Figure 11 (c) is a diagram showing, with the horizontal axis serving as the time axis, the rectangular B, G, and R beams illuminating the screen of the reflective light modulator 340. The B, G, and R beams vertically scan the screen of the reflective light modulator 340 along the scanning direction SD, completing the scanning of one screen in one frame. The B, G, and R beams are configured to be non-overlapping to prevent color mixing at the boundaries of the various color regions. 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 greater than 1 / 6 and less than 1 / 3 of the vertical width of the screen of the reflective light modulator 340.

[0157] 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 photosynthesizing unit, wherein the illumination component has multiple semiconductor lasers, a collimating lens, an integrator illumination system and a deflection device, and the photosynthesizing unit synthesizes the illumination light output by the illumination components of different colors of light, and 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 is enlarged and projected onto the reflective light modulation device.

[0158] In the illumination system of the projection display device according to this embodiment, the light diffusion device having a dynamic light diffusion surface is arranged between the laser light source and the incident surface of the integrator optical system. Figure 5 As shown, the light diffuser 402 is positioned between the laser module LM and the incident surface INP of the rod-shaped optical integrator 403. With this configuration, the portion of the laser beam irradiating the light diffuser surface DIF is moved at an appropriate speed, thereby reducing the temporal and spatial coherence of the laser beam incident on the integrator optical system. This prevents interference fringes and other light distributions caused by the superposition of light beams in the integrator optical system. By moving the light diffuser surface at an appropriate speed, the effective illumination distribution within the rectangular illumination area IM1 can be made extremely uniform, consistent with human visual characteristics. Therefore, according to this embodiment, the screen of the reflective light modulator is illuminated by reproducing the uniformly illuminated rectangular illumination area IM1, thereby displaying a high-quality projected image.

[0159] In this embodiment, the three laser beams (B, G, and R) are diffused by a single light diffuser 402, which is rotated by a single motor 412. This reduces the number of components compared to using separate motors and light diffusers for each color. Furthermore, by sharing the rod-shaped optical integrator for both B and G light in the integrator illumination system, the number of components is reduced and the space occupied by the optical path can be made more compact. This results in a low-cost and compact projection display device.

[0160] According to this embodiment, in the field of projection-type image display devices that modulate laser light according to image signals and project the resultant image, a device that is compact, easy to drive and control, and has high light utilization efficiency can be realized.

[0161] [Implementation Method 2]

[0162] Regarding the projection display device 1005 according to the second embodiment, refer to Figure 13 The description of the parts common to the first embodiment will be simplified or omitted.

[0163] The projection display device 1005 of this embodiment has the same Figure 1 The structure of the projection display device 1004 of the embodiment 1 described above is similar, but the structure of the light combining unit is different from that of the embodiment 1. In the embodiment 1, the B light and the G light are guided to a single dichroic mirror 224, reflected, and combined with the transmitted R light, but in the present embodiment, the dichroic mirror 224a and the dichroic mirror 224b are used for combination.

[0164] (Photosynthesis Department)

[0165] The dichroic mirror 224a has the optical property of transmitting R light and reflecting B light, while the dichroic mirror 224b has the optical property of transmitting both R and B light and reflecting G light. First, the dichroic mirror 224a combines the R and B light, and then the dichroic mirror 224b combines the G light guided by the optical path conversion mirror 330c. The optical components are arranged so that the optical axis centers of the front transfer lens 201B for B light, the front transfer lens 201G for G light, and the front transfer lens 201R for R light overlap on the dichroic mirror 224b. The light combining unit aligns the travel directions of the B light (dashed line), G light (solid line), and R light (single-dot chain line) to the positive Z direction, i.e., toward the rear transfer lens 202.

[0166] (Transfer optical system)

[0167] The first transfer lens (first transfer optical system) is composed of a front transfer lens 201B, a front transfer lens 201G, and a front transfer lens 201R, each provided for each color, and a rear transfer lens 202, which is common to all colors. The rectangular irradiation area IM1 formed by the laser beams of each color is magnified and transferred into a rectangular secondary transfer image IM2. Both the front transfer lens 201 and the rear transfer lens 202 are convex lenses with positive refractive power. The optical path length of the first transfer optical system, that is, the distance from the rectangular irradiation area IM1 to the rectangular secondary transfer image IM2, can be configured to be equal for each color.

[0168] In this embodiment, compared with the first embodiment, the position of the R deflector 210R is arranged in the negative direction of the X axis, and the position of the B deflector 210B is arranged in the positive direction of the X axis. Figure 13 The deflection directions DB, DG, and DR shown are deflected, and the B deflector 210B, the G deflector 210G, and the R deflector 210R are all along Figure 8 The R direction shown in (a) rotates.

[0169] In addition to achieving the same effects as those of the first embodiment, this embodiment can also reduce the size of the optical path space in the X direction, thereby making the outer shape of the projection display device in the X direction compact.

[0170] [Implementation Method 3]

[0171] Regarding the projection display device 1006 according to Embodiment 3, refer to Figure 14 The description of the parts common to those in Embodiment 1 or 2 will be simplified or omitted.

[0172] Similar to the projection display device 1004 of the first embodiment, the projection display device 1006 of this embodiment includes an integrator optical system having a movable light diffuser, a light combining unit, and a relay optical system. Figure 14 As shown, in this embodiment, the rotation axis CX of the light diffuser 402, the axial direction of the rod optical integrator 403R, and the axial direction of the rod optical integrator 403GB are different in that they are all along the Z direction.

[0173] Furthermore, in order to make the rectangular illumination area IM1 of each color Figure 14 The deflection directions DB, DG, and DR are shown. In this embodiment, the deflector 210B is used to deflect the Figure 8 The G deflector 210G and the R deflector 210R rotate in the R direction as shown in (a). Figure 8 The R direction shown in (a) rotates in the opposite direction.

[0174] As in Embodiment 1, the light combining unit guides the B and G lights to a single dichroic mirror 224, where they are reflected and combined with the transmitted R light. However, in this embodiment, the optical path structure for guiding the light of each color to the dichroic mirror 224 differs from that in Embodiment 1. In this embodiment, the traveling direction of the R light deflected by the R deflector 210R is changed from the negative X direction to the positive Z direction using an optical path conversion mirror 330 b, and the light is then incident on the dichroic mirror 224.

[0175] In addition to achieving the same effects as Embodiment 1, this embodiment further reduces the X-direction dimension of the optical path space by arranging the laser modules LM-B, LM-G, and LM-R on the left side of the figure, thereby making the X-direction dimension of the projection display device more compact.

[0176] [Implementation Method 4]

[0177] Regarding the projection display device 1007 according to the fourth embodiment, refer to Figure 15 The description of the parts common to the first embodiment will be simplified or omitted.

[0178] In the first to third embodiments, since deflectors rotated by motors are provided on the optical paths of the B light, the G light, and the R light, the number of parts constituting the deflection mechanism is large. Figure 15 As shown, the B light, the G light, and the R light are deflected and scanned using a deflector 210 a composed of a single motor and a single rotating body.

[0179] (Deflector)

[0180] like Figure 15 As shown, a deflector 210a is disposed between the rear convex lens 406b of the relay lens for each color of light B, G, and R and the rectangular illumination area IM1 of each color. The deflector 210a is a deflection device that can deflect and scan the three rectangular illumination areas with a single device.

[0181] Figure 16 (a) is a plan view of the deflector 210a as viewed from the side where the rear convex lens 406b for B light and the rear convex lens 406b for G light are arranged. Figure 16 (b) is a side view of the deflector 210a viewed from a direction perpendicular to the rotation axis AX. Figure 16 (c) is a bottom view of the deflector 210a as viewed from the side where the rear convex lens 406b for R light is provided. Figure 16 (a) and Figure 16 In (c), the rotation direction is shown as RO.

[0182] like Figure 16 As shown in (a), a reflective surface 213a and a reflective surface 213b as strip-shaped optical surfaces are provided on the upper surface of the disk-shaped base 211. The reflective surface 213a and the reflective surface 213b are provided along concentric circles with different radii centered on the rotation axis AX. Figure 16 As shown in FIG. 2( c ), a reflective surface 213 c as a strip-shaped optical surface is provided on the lower surface of the disk-shaped base 211 along a circle centered on the rotation axis AX.

[0183] like Figure 16 As shown in (b), the disc-shaped base 211 is formed by stacking and integrating the substrates 211a, 211b and 211c, each of which has a reflective surface. However, the base 211 is not necessarily formed by stacking and integrating three substrates. For example, Figure 17 (a)~ Figure 17 (c) shows a side view of the structure. Figure 17 (a) is an example in which a substrate 211a having a reflecting surface 213a and a reflecting surface 213b on one side and a substrate 211c having a reflecting surface 213c are stacked and integrated to form a base 211. Figure 17 (b) is an example in which a substrate 211c provided with a reflecting surface 213a and a reflecting surface 213c and a substrate 211b provided with a reflecting surface 213b are stacked and integrated to form the base 211. Figure 17 (c) is an example in which a reflecting surface 213 a , a reflecting surface 213 b , and a reflecting surface 213 c are provided on a base 211 which is originally a single substrate.

[0184] On each reflecting surface, Figure 8 (a)~ Figure 9 Similarly, the reflective surface 213 described in (b) is configured as an inclined surface capable of uniformly and recursively deflecting and scanning the laser beam in a predetermined direction. However, in order to prevent the G light deflected and scanned by the reflective surface 213a, the B light deflected and scanned by the reflective surface 213b, and the R light deflected and scanned by the reflective surface 213c from overlapping when combined by the light combining unit, the reflective surfaces are configured so that the starting and ending points of their inclination, that is, the positions NC where the inclination angles of the reflective surfaces are discontinuous, are offset from each other when viewed along the circumferential direction.

[0185] refer to Figure 15It can be seen that, on the upper surface of the deflector 210a, the position irradiated by the B light is located on the opposite side of the rotation axis AX relative to the position irradiated by the G light. In addition, on the lower surface of the deflector 210a, the position irradiated by the R light is located on the opposite side of the rotation axis AX relative to the position irradiated by the B light on the upper surface of the deflector 210a. The inclination of each reflecting surface is set so that when the light beams of various colors reflected at each irradiation position are synthesized by the dichroic mirror 224 as the light synthesizing unit, the phases of the deflection scan are shifted by 120 degrees from each other. For example, Figure 16 In (a), when the position NC where the inclination of the reflecting surface 213a is discontinuous is at the 12 o'clock position, the position NC where the inclination of the reflecting surface 213b is discontinuous is at the 2 o'clock position. Figure 16 In (c), the position NC where the inclination of the reflecting surface 213c is discontinuous is located at 8 o'clock. Figure 16 The upper surface shown in (a) is Figure 16 The lower surface shown in (c) of FIG. 2 shows the base 211 with its rotational direction RO reversed. To prevent the rectangular irradiation areas from overlapping during recursive deflection scanning, the phases of the changes in the inclination angles of the reflective surfaces at the irradiation position on the circular plate of the deflector are staggered along the rotational direction.

[0186] In this embodiment, to guide the B light deflected by the deflector 210a to the dichroic mirror 224, which serves as a light combining unit, a front-side re-reflecting lens 201B for B, an optical path conversion mirror 330e, and an optical path conversion mirror 330i are provided. Furthermore, to guide the G light deflected by the deflector 210a to the dichroic mirror 224, which serves as a light combining unit, a front-side re-reflecting lens 201G for G, an optical path conversion mirror 330h, a dichroic mirror 221c, and an optical path conversion mirror 330g are provided. The dichroic mirror 221c has the optical property of reflecting the G light and transmitting the R light, and is shared by both the G and R light. Furthermore, to guide the R light deflected by the deflector 210a to the dichroic mirror 224, which serves as a light combining unit, a front-side re-reflecting lens 201R for R, an optical path conversion mirror 330f, the aforementioned dichroic mirror 221c, and an optical path conversion mirror 330g are provided.

[0187] In addition to achieving the same effects as those of the first embodiment, this embodiment uses a deflector 210 a composed of a single motor and a single rotating body to deflect and scan B light, G light, and R light, thereby reducing the number of parts of the deflection mechanism.

[0188] [Implementation 5]

[0189] Regarding the projection display device 1008 according to Embodiment 5, refer to Figure 18This embodiment is similar to the fourth embodiment in that a deflector 210a composed of a single motor and a single rotating body is used, and the description of the parts common to the fourth embodiment will be simplified or omitted.

[0190] Including embodiment 4, in the above embodiments, the laser module LM-B for B, the laser module LM-G for G, and the laser module LM-R for R are arranged separately, but in this embodiment, there is a laser module LM-BGR that integrates the laser modules of three colors.

[0191] Figure 19 (a) is a perspective view of the laser module LM-BGR. In each laser module, the semiconductor lasers and collimating lenses 102 are arranged two-dimensionally in a 4×5 matrix. However, the arrangement is not necessarily limited to a 4×5 matrix; the number of rows or columns can be varied as appropriate. Terminal 104 is a power supply terminal for supplying power to the semiconductor lasers in each column.

[0192] To ensure uniform brightness across the entire array of semiconductor lasers of the same color, semiconductor lasers of the same color are typically arranged in the same row and often electrically connected in series. Furthermore, since semiconductor lasers emitting R light have lower brightness than semiconductor lasers emitting B light and G light, to achieve a good white balance in the illumination light, the number of semiconductor lasers emitting R light is greater than the number of semiconductor lasers emitting B light and G light.

[0193] exist Figure 19 In the example of (a), the laser module LM-BGR includes two vertical rows of red semiconductor lasers R, one vertical row of blue semiconductor lasers B, and one vertical row of green semiconductor lasers G.

[0194] exist Figure 19 In (b), the wavelengths of the output lights of the semiconductor lasers of various colors used in this embodiment are exemplified. Respectively, the output light of the blue semiconductor laser B is contained in the wavelength region of 440 (nm) to 465 (nm), the output light of the green semiconductor laser G is contained in the wavelength region of 520 (nm) to 560 (nm), and the output light of the red semiconductor laser R is contained in the wavelength region of 620 (nm) to 650 (nm). In addition, due to manufacturing deviations, etc., the output wavelengths of the various semiconductor lasers installed in the laser module sometimes have a deviation of about 10 nm within the above-mentioned wavelength region. In addition, the emission wavelength of the semiconductor laser can also be set within a wavelength region other than the above-mentioned.

[0195] If the direction in which semiconductor lasers of different emission colors are arranged in the laser module LM-BGR is set to DIR, then in the projection display device 1008 ( Figure 18 ), the laser module LM-BGR is arranged so that DIR is along the X direction. Thus, the laser beams of various colors output from the laser module LM-BGR advance in the positive Z direction.

[0196] The B light output from the laser module LM-BGR is incident on the dichroic mirror 223 having the optical property of transmitting the B light and reflecting the G light. After being transmitted through the dichroic mirror 223, the direction of travel is changed to the positive X direction by the optical path conversion mirror 330l, and then transmitted through the dichroic mirror 223 again and is incident on the focusing lens 401 shared by BG, thereby being focused onto the light diffuser 402.

[0197] The G light output from the laser module LM-BGR is reflected by the dichroic mirror 223 having the optical characteristic of transmitting the B light and reflecting the G light, and its traveling direction is changed to the positive X direction. The light is then incident on the condensing lens 401 shared by B and G, and is condensed by the light diffuser 402 .

[0198] The R light output from the laser module LM-BGR is reflected by the optical path conversion mirror 330 k and its traveling direction is changed to the positive X direction. The R light is incident on the condensing lens 401 for R and is condensed by the light diffuser 402 .

[0199] Here, the R light output from the laser module LM-BGR is emitted from two rows of semiconductor devices, while the B light and G light are emitted from one row of semiconductor devices, respectively. Therefore, the angle α-R formed by the R light being focused by the condenser lens 401 is greater than the angle α-GB formed by the B and G light being focused by the condenser lens 401.

[0200] In this embodiment, reference Figure 12 The light diffuser 402 described in (b) has a light diffuser surface DIF1 and a light diffuser surface DIF2 with different diffusion characteristics. Specifically, the light diffuser 402 is configured so that the diffusion capability of the light diffuser surface DIF2 is greater than that of the light diffuser surface DIF1. The light diffuser surface DIF2 diffuses the B and G light, while the light diffuser surface DIF1 diffuses the R light. This ensures that the scattering characteristics of the B, G, and R light rays transmitted through the light diffuser 402 are consistent, thereby achieving a good color balance in the illumination light illuminating the reflective light modulator 340.

[0201] The optical arrangement in front of the light diffuser 402 is substantially the same as that in the fourth embodiment.

[0202] In addition to achieving the same effects as those of the fourth embodiment, this embodiment can improve the intensity of illumination light for illuminating the reflective light modulator 340 while improving color balance by using the laser module LM-BGR including a plurality of R light semiconductor lasers.

[0203] [Implementation Method 6]

[0204] Regarding the projection display device 1009 according to Embodiment 6, refer to Figure 20 This embodiment has many similarities with embodiment 5, but Figure 20 As shown, the light diffuser 402 differs in that the rotation axis CX, the axial direction of the rod optical integrator 403R, and the axial direction of the rod optical integrator 403GB are all along the Z direction. Furthermore, the optical system that uses the light combining unit 225 to combine the rectangular illumination areas IM1 of various colors deflected by the deflector 210a is also different from that of the fifth embodiment.

[0205] In this embodiment, a dichroic mirror having optical properties that transmit B and G light and reflect R light is used as the light combining unit 225. To guide the B light deflected by the deflector 210a to the light combining unit 225, a front-side re-reflecting lens 201B for B, an optical path conversion mirror 330e, and a dichroic mirror 223 having optical properties that transmit B light and reflect G light are provided. Furthermore, to guide the G light deflected by the deflector 210a to the light combining unit 225, a front-side re-reflecting lens 201G for G, an optical path conversion mirror 330h, and the aforementioned dichroic mirror 223 are provided. Furthermore, to guide the R light deflected by the deflector 210a to the light combining unit 225, a front-side re-reflecting lens 201R for R and an optical path conversion mirror 330f are provided.

[0206] In addition to achieving the same effects as in Embodiment 5, this embodiment can reduce the size of the optical path space in the X direction by placing the laser module LM-BGR on the left side of the figure, thereby making the projection display device compact in the X direction.

[0207] [Implementation 7]

[0208] Regarding the projection display device 1010 according to Embodiment 7, refer to Figure 21 The description of the parts common to any of the other embodiments will be simplified or omitted.

[0209] The projection display device 1010 according to this embodiment is similar to that of Embodiment 1 in that the three laser beams of B, G, and R colors are diffused by a single light diffuser 402, and this single light diffuser 402 is rotated by a single motor 412. Therefore, as in Embodiment 1, the number of parts can be reduced compared to the case where a motor and light diffuser are provided for each color.

[0210] In this embodiment, the output lights of laser modules LM-B, LM-G, and LM-R are pre-superimposed and combined before being incident on a common condenser lens 401 for laser modules B and R, where they are focused onto a light diffuser 402. Specifically, the output lights of laser modules LM-B and LM-G are combined by a dichroic mirror 231, which has the optical property of transmitting G light and reflecting B light. Furthermore, the B, G, and R lights are combined by a dichroic mirror 232, which has the optical property of reflecting B and G light and transmitting R light.

[0211] The B light, G light, and R light emitted from the exit surface of the rod optical integrator 403 pass through the front convex lens 406 a as a part of the relay lens, and are then separated into the B light, R light, and G light by the cross prism 501 as a separation element.

[0212] The B light separated by the cross prism 501 has its optical path changed by the optical path conversion mirror 330, then passes through the rear convex lens 406b, which is part of the relay lens, and is incident on the B deflector 210B, where it is deflected. The B light deflected by the B deflector 210B passes through the front relay lens 201B and enters the cross prism 502.

[0213] The R and G light separated by the cross prism 501 have their optical paths changed by the optical path conversion mirror 330. The light then enters the dichroic mirror 233, which has the optical property of reflecting the G light and transmitting the R light. The G light reflected by the dichroic mirror 233 passes through the rear convex lens 406b, part of the relay lens, and enters the G deflector 210G, where it is deflected. The G light deflected by the G deflector 210G passes through the front relay lens 201G and enters the cross prism 502. The R light transmitted by the dichroic mirror 233 passes through the rear convex lens 406b, part of the relay lens, and enters the R deflector 210R, where it is deflected. The R light deflected by the R deflector 210R passes through the front relay lens 201R and enters the cross prism 502.

[0214] Cross prism 502 changes the direction of B light traveling in the positive X direction to the positive Z direction without affecting the direction of G light traveling in the positive Z direction, and changes the direction of R light traveling in the negative X direction to the positive Z direction. In other words, similar to dichroic mirror 224 in Embodiment 1, cross prism 502 in this embodiment functions as a combining unit that combines B light, G light, and R light. Since the structure starting from the combining unit is the same as that in Embodiment 1, its description will be omitted.

[0215] In this embodiment, since the rod-shaped optical integrator 403 for B light, G light, and R light is shared in the integrator illumination system, the number of parts can be reduced, thereby realizing a low-cost and compact projection display device.

[0216] [Embodiment 8]

[0217] Regarding the eighth embodiment which is a modified example of the first embodiment, refer to Figure 22 The description of matters common to the first embodiment will be simplified or omitted.

[0218] exist Figure 1 In the example shown, as described above, a single rotatable light diffuser 402 is positioned near the incident surface of the rod-shaped optical integrator to dynamically diffuse the B, G, and R laser beams. Here, if the purpose of light diffuser 402 is to reduce light capture loss at the incident surface INP of the rod-shaped optical integrator 403 and improve utilization efficiency, the light diffuser surface need not necessarily be movable. In other words, the B, G, and R laser beams can be diffused statically rather than dynamically.

[0219] Figure 22 The figure shows an example of a projection type image display device in which a light diffuser 402a is fixedly arranged near the incident surface of a rod-shaped optical integrator 403R, and a light diffuser 402b is fixedly arranged near the incident surface of a rod-shaped optical integrator 403GB. The light diffuser 402a has a light diffuser surface with an area larger than the irradiation spot of the laser beam R, and the light diffuser 402b has a light diffuser surface with an area larger than the irradiation spot of each of the laser beams G and B. According to this embodiment, since there is no need to provide a driving mechanism (e.g., a driving mechanism) for dynamically moving the light diffuser, Figure 1 motor 412), thereby realizing a projection image display device which is compact, easy to drive and control, and has high light utilization efficiency.

[0220] Furthermore, the fixedly configured light diffuser 402a and light diffuser 402b can be separate components or an integrated component. If the light diffuser 402a, which is irradiated with R light (a laser beam having a first wavelength), serves as the first diffusion region, and the light diffuser 402b, which is irradiated with B and G light (laser beams having a second wavelength), serves as the second diffusion region, then since the first wavelength is greater than the second wavelength, the diffusion capacity of the first diffusion region is preferably smaller than that of the second diffusion region. Furthermore, the number of semiconductor lasers emitting light at the first wavelength (R) can be greater than the number of semiconductor lasers emitting light at the second wavelength (either B or G).

[0221] [Implementation Method 9]

[0222] Hereinafter, regarding Embodiment 9 which is a modified example of Embodiment 5, refer to the attached Figure 23 For matters common to Implementation 5, the description is simplified or omitted. In Implementation 5, Figure 18 As shown, a laser module LM-BGR, which integrates three laser modules, is used as the light source. A single, rotatable light diffuser 402 is positioned near the incident surface of a rod-shaped optical integrator to dynamically diffuse the B, G, and R laser lights. Here, if the purpose of light diffuser 402 is to reduce light capture loss at the incident surface INP of the rod-shaped optical integrator 403 and improve utilization efficiency, a movable light diffusion surface is not necessarily required. In other words, the B, G, and R laser lights can be diffused statically rather than dynamically.

[0223] Figure 23 The figure shows an example of a projection-type image display device in which a light diffuser 402a is fixedly positioned near the incident surface of a rod-shaped optical integrator 403R, and a light diffuser 402b is fixedly positioned near the incident surface of a rod-shaped optical integrator 403GB. The light diffuser 402a has a light diffusing surface with an area larger than the illumination spot of the laser beam R, and the light diffuser 402b has a light diffusing surface with an area larger than the illumination spot of each of the laser beams G and B. This embodiment eliminates the need for a drive mechanism (e.g., a motor) for dynamically moving the light diffuser, thereby achieving a compact projection-type image display device that is easily driven and controlled, and has high light utilization efficiency.

[0224] Furthermore, the fixedly configured light diffuser 402a and light diffuser 402b can be separate components or an integrated component. If the light diffuser 402a, which is irradiated with R light (a laser beam having a first wavelength), serves as the first diffusion region, and the light diffuser 402b, which is irradiated with B and G light (laser beams having a second wavelength), serves as the second diffusion region, then since the first wavelength is greater than the second wavelength, the diffusion capacity of the first diffusion region is preferably smaller than that of the second diffusion region. Furthermore, the number of semiconductor lasers emitting light at the first wavelength (R) can be greater than the number of semiconductor lasers emitting light at the second wavelength (either B or G).

[0225] [Implementation 10]

[0226] Regarding the embodiment 10 as a modification of the embodiment 7, refer to the attached Figure 24 For matters common to Implementation 7, the description is simplified or omitted. In Implementation 7, Figure 21 As shown, the output lights of the laser module LM-B, the laser module LM-G, and the laser module LM-R are pre-superimposed and synthesized, and then incident on the focusing lens 401 shared by BGR, so as to be focused on the light diffuser 402. In embodiment 7, a single rotatable light diffuser 402 is arranged near the incident surface of the single rod-shaped optical integrator 403. Here, as the effect of the light diffuser 402, if the purpose is to suppress the capture loss of light on the incident surface INP of the rod-shaped optical integrator 403 and improve the utilization efficiency, it is not necessary to make the light diffusion surface movable. That is, the superimposed B laser, G laser, and R laser can also be diffused statically rather than dynamically. In addition, the number of multiple semiconductor laser devices that emit light at the first wavelength (R) can be greater than the number of multiple semiconductor laser devices that emit light at the second wavelength (either B or G).

[0227] Figure 24 The figure shows an example of a projection-type image display device in which a light diffuser 402 is fixedly positioned near the incident surface of a rod-shaped optical integrator 403R. The light diffuser 402 has a light diffusing surface larger than the area of ​​each of the illumination spots of the respective color laser beams. This configuration eliminates the need for a drive mechanism (e.g., a motor) to dynamically move the light diffuser, thereby achieving a compact projection-type image display device that is easily driven and controlled, and has high light utilization efficiency.

[0228] In addition, in embodiment 7, as Figure 21As shown, after the B light, G light, and R light emitted from the exit surface of the rod-shaped optical integrator 403 pass through the front convex lens 406a as a part of the relay lens, the three colors of light are separated using the orthogonal prism 501 and the dichroic mirror 233. In this embodiment, as shown in FIG. Figure 24 As shown, the light passing through the front convex lens 406a is color-separated using a dichroic mirror 234 and a dichroic mirror 235. The dichroic mirror 234 has an optical characteristic of reflecting B light and G light while transmitting R light. The dichroic mirror 235 has an optical characteristic of reflecting B light while transmitting G light. After passing through the front convex lens 406a, the R light enters the R deflector 210R with zero reflections. The B light is reflected by the dichroic mirror 234 and the dichroic mirror 235 and enters the B deflector 210B with two reflections. The G light is reflected by the dichroic mirror 234 and the optical path conversion mirror 330 and enters the G deflector 210G with two reflections. Therefore, the rotation directions of the R deflectors 210R, B deflectors 210B, and G deflectors 210G can be made the same, and the scanning direction of the rectangular irradiation area IM1 can be made the same.

[0229] In addition, when synthesizing the light of various colors for deflection scanning, in embodiment 7, as shown in FIG. Figure 21 As shown, the orthogonal prism 502 is used for synthesis, but in this embodiment, the optical path conversion mirror 330, the dichroic mirror 235, and the dichroic mirror 236 are used for synthesis. The dichroic mirror 235 has an optical characteristic of reflecting the B light and transmitting the G light. The dichroic mirror 236 has an optical characteristic of reflecting the R light and transmitting the B light and the G light. According to this structure, the light of each color deflected and scanned by the deflector is synthesized after being reflected once. Figure 24 For example, since there is no need for Figure 21 By providing two orthogonal prisms as in the example above, it is possible to realize a projection type image display device which is compact, easy to drive and control, and has high light utilization efficiency.

[0230] In addition, Figure 24 In the example shown, laser module LM-B, laser module LM-G, and laser module LM-R are arranged separately, but Figure 25 As shown, a laser module LM-BGR, which integrates three color laser modules, can also be used. Furthermore, the number of semiconductor lasers emitting light at the first wavelength (R) can be greater than the number of semiconductor lasers emitting light at the second wavelength (either B or G). The B, G, and R lights are synthesized by a dichroic mirror 237 having the optical property of reflecting R light and transmitting B and G light. This method allows for a compact light source configuration.

[0231] [Other embodiments]

[0232] Furthermore, the present invention is not limited to the embodiments described above, and various modifications are possible within the technical concept of the present invention. For example, the light diffuser, deflector, and laser module may be replaced with components used in different embodiments, or components used in different embodiments may be combined to form a projection display device.

[0233] Regarding the rod-shaped optical integrator 403 described in the embodiment, 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 is cited as an example, but a light rod in which the shape of the incident surface INP and the shape of the exit surface EXP are different, such as a so-called conical light rod, can also be used.

[0234] The image-reflecting optical systems, namely the first relay lens (front relay lens 201 and rear relay lens 202), the second relay lens 320 (front relay lens 321 and rear relay lens 322), and the relay lens 406, are preferably configured to be bilaterally telecentric, but other configurations are also possible. For example, one or more of these relay systems may employ so-called anamorphic optical systems (anamorphic lenses), which have different optical characteristics in two cross-sections around the optical axis. Using anamorphic systems for the first relay lens, the second relay lens, and the relay lens allows for magnification reduction or magnification in only one direction, thereby adjusting the NA and aspect ratio of the transferred image, further improving light utilization efficiency.

[0235] Furthermore, the colors of the illumination light source are not limited to the three colors of R, G, and B. Light sources with different wavelengths than these three colors can also be used. For example, a yellow light source can be added to provide four colors. Furthermore, the integrator illumination system used for each color of light does not necessarily have to be the same. Furthermore, depending on the application of the projection display device, a projection display device may also use light sources with only two colors of different wavelengths, for example, only R and G.

[0236] The disclosure of this specification includes the following structures.

[0237] [Structure 1]

[0238] A projection display device, characterized by comprising:

[0239] a first collimating lens for collimating a plurality of laser beams output from a plurality of semiconductor lasers emitting light at a first wavelength;

[0240] a first condensing lens, for focusing the multiple laser beams collimated by the first collimating lens;

[0241] a second collimating lens for collimating a plurality of laser beams output from a plurality of semiconductor lasers emitting light at a second wavelength;

[0242] a second condensing lens, for focusing the multiple laser beams collimated by the second collimating lens;

[0243] a light diffuser having a light diffusing surface having an area larger than an irradiation spot of the laser beam of the first wavelength focused by the first condensing lens and an irradiation spot of the laser beam of the second wavelength focused by the second condensing lens;

[0244] a first integrator illumination system for superimposing the laser beams of the first wavelength diffused by the light diffusion surface to form a rectangular irradiation area of ​​the first wavelength;

[0245] a second integrator illumination system for superimposing the laser beams of the second wavelength diffused by the light diffusion surface to form a rectangular irradiation area of ​​the second wavelength;

[0246] a first deflection unit arranged at a position closer to the first integrator illumination system than a position where the rectangular illumination area of ​​the first wavelength is formed by the first integrator illumination system;

[0247] a second deflection unit arranged at a position closer to the second integrator illumination system than a position where the second integrator illumination system forms a rectangular illumination area of ​​the second wavelength;

[0248] a projection optical system that enlarges and projects the rectangular illumination area of ​​the first wavelength deflected and scanned by the first deflection unit and the rectangular illumination area of ​​the second wavelength deflected and scanned by the second deflection unit onto a reflective light modulation device; and

[0249] The projection lens projects the image light output by the reflective light modulation device.

[0250] [Structure 2]

[0251] The projection display device according to Structure 1 is characterized in that:

[0252] The light diffuser can dynamically change the position of the irradiation spot of the laser beam with the first wavelength and the position of the irradiation spot of the laser beam with the second wavelength on the light diffuser surface by moving the light diffuser surface.

[0253] [Structure 3]

[0254] The projection display device according to structure 1 or 2 is characterized in that:

[0255] The light diffuser includes the light diffuser surface provided along a circumference centered on a rotation axis, and the light diffuser surface is rotatable about the rotation axis.

[0256] [Structure 4]

[0257] The projection display device according to structure 1 or 2 is characterized in that:

[0258] The light diffusion device includes a light-transmitting substrate provided with the light diffusion surface, and a mechanism for rotating, moving in a curved line, or moving in a straight line the substrate.

[0259] [Structure 5]

[0260] The projection display device according to any one of Structures 1 to 4 is characterized in that:

[0261] The light diffuser includes a first diffusion region irradiated by the first wavelength laser beam and a second diffusion region irradiated by the second wavelength laser beam. The first wavelength is longer than the second wavelength, and the diffusion capability of the first diffusion region is smaller than that of the second diffusion region.

[0262] [Structure 6]

[0263] The projection display device according to any one of Structures 1 to 4 is characterized in that:

[0264] The light diffusion device includes a first diffusion region irradiated with the laser beam of the first wavelength and a second diffusion region irradiated with the laser beam of the second wavelength.

[0265] The number of semiconductor lasers emitting light at the first wavelength is greater than the number of semiconductor lasers emitting light at the second wavelength, and the diffusion capability of the first diffusion region is smaller than the diffusion capability of the second diffusion region.

[0266] [Structure 7]

[0267] The projection display device according to any one of Structures 1 to 6 is characterized in that:

[0268] Each of the first deflecting unit and the second deflecting unit includes an optical surface rotatable about a rotation axis and arranged along a circumference centered about the rotation axis.

[0269] The optical surface is configured so that the inclination angle relative to the rotation axis changes along the circumference.

[0270] The tilt angle is configured so that when the optical surface is continuously rotated at a constant speed, the laser beam is recursively deflected in a constant direction at a constant deflection speed.

[0271] [Structure 8]

[0272] The projection display device according to any one of Structures 1 to 6 is characterized in that:

[0273] The first deflecting unit and the second deflecting unit are integrated,

[0274] Each of the first deflecting unit and the second deflecting unit includes an optical surface rotatable about a common rotation axis and arranged along a circumference centered on the rotation axis.

[0275] The optical surface is configured so that the inclination angle relative to the rotation axis changes along the circumference.

[0276] The tilt angle is configured so that when the optical surface is continuously rotated at a constant speed, the laser beam is recursively deflected in a constant direction at a constant deflection speed.

[0277] [Structure 9]

[0278] The projection display device according to any one of Structures 1 to 8 is characterized in that:

[0279] The plurality of semiconductor lasers emitting light at the first wavelength are arranged so that the directions of their slow axes and fast axes coincide with each other.

[0280] The long side direction of the rectangular irradiation area of ​​the first wavelength is the direction of the slow axis,

[0281] The short side direction of the rectangular irradiation area of ​​the first wavelength is the direction of the fast axis,

[0282] The first deflection unit deflects and scans a rectangular irradiation area of ​​the first wavelength along the short side direction.

[0283] [Structure 10]

[0284] The projection display device according to Structure 9 is characterized in that:

[0285] The plurality of semiconductor lasers emitting light at the second wavelength are arranged so that the directions of their slow axes and fast axes coincide with each other.

[0286] The long side direction of the rectangular irradiation area of ​​the second wavelength is the direction of the slow axis,

[0287] The short side direction of the rectangular irradiation area of ​​the second wavelength is the direction of the fast axis,

[0288] The second deflection unit deflects and scans the rectangular irradiation area of ​​the second wavelength along the short side direction.

[0289] [Structure 11]

[0290] The projection display device according to any one of Structures 1 to 10 is characterized in that:

[0291] The first integrator illumination system and the second integrator illumination system include a light rod on which the laser light transmitted through the light diffuser enters, and a relay lens for relaying an image on an exit surface of the light rod.

[0292] [Structure 12]

[0293] The projection display device according to Structure 11 is characterized in that:

[0294] The light rod is a prism made of optical material, or a hollow cylinder with a reflective inner surface.

[0295] [Structure 13]

[0296] The projection display device according to any one of Structures 1 to 12 is characterized in that:

[0297] Any one of the first integrator illumination system, the second integrator illumination system, and the relay optical system includes an anamorphic lens.

[0298] [Structure 14]

[0299] The projection display device according to any one of Structures 1 to 13, wherein the relay optical system comprises:

[0300] a first transfer optical system for enlarging and transferring the rectangular irradiation area of ​​the first wavelength and the rectangular irradiation area of ​​the second wavelength onto a light diffusion plate; and

[0301] The second projection optical system enlarges and projects the rectangular illumination area of ​​the first wavelength and the rectangular illumination area of ​​the second wavelength, which are enlarged and projected onto the light diffusion plate, onto the reflective light modulation element.

[0302] [Structure 15]

[0303] The projection display device according to any one of Structures 1 to 14 is characterized in that:

[0304] The device further comprises: a third collimating lens for collimating a plurality of laser beams outputted from a plurality of semiconductor lasers emitting light at a third wavelength; a third integrator illumination system; and a third deflection unit.

[0305] The plurality of laser beams of the third wavelength collimated by the third collimating lens are condensed by the second condensing lens and condensed onto the light diffuser.

[0306] The laser beams of the third wavelength diffused by the light diffusion surface are superimposed by the third integrator illumination system to form a rectangular irradiation area of ​​the third wavelength.

[0307] The third deflection unit is arranged at a position closer to the third integrator illumination system than a position where the rectangular illumination area of ​​the third wavelength is formed by the third integrator illumination system.

[0308] The projection optical system magnifies and projects the rectangular irradiation area of ​​the first wavelength deflected and scanned by the first deflection unit, the rectangular irradiation area of ​​the second wavelength deflected and scanned by the second deflection unit, and the rectangular irradiation area of ​​the third wavelength deflected and scanned by the third deflection unit onto the reflective light modulator.

[0309] [Structure 16]

[0310] A projection display device comprising:

[0311] a first collimating lens for collimating a plurality of laser beams output from a plurality of semiconductor lasers emitting light at a first wavelength;

[0312] a second collimating lens for collimating a plurality of laser beams output from a plurality of semiconductor lasers emitting light at a second wavelength;

[0313] a synthesis unit for superimposing and synthesizing the plurality of laser beams collimated by the first collimating lens and the plurality of laser beams collimated by the second collimating lens;

[0314] a first condensing lens for focusing the multiple laser beams synthesized by the synthesis unit;

[0315] a light diffusion device having a light diffusion surface, wherein the area of ​​the light diffusion surface is larger than the irradiation spot of the plurality of laser beams focused by the first condensing lens;

[0316] a first integrator illumination system for superimposing the laser beams of the first wavelength among the plurality of laser beams diffused by the light diffusion surface to form a rectangular irradiation area of ​​the first wavelength;

[0317] a second integrator illumination system for superimposing the laser beams of the second wavelength among the plurality of laser beams diffused by the light diffusion surface to form a rectangular irradiation area of ​​the second wavelength;

[0318] a first deflection unit arranged at a position closer to the first integrator illumination system than a position where the rectangular illumination area of ​​the first wavelength is formed by the first integrator illumination system;

[0319] a second deflection unit arranged at a position closer to the second integrator illumination system than a position where the second integrator illumination system forms a rectangular illumination area of ​​the second wavelength;

[0320] a projection optical system that enlarges and projects the rectangular illumination area of ​​the first wavelength deflected and scanned by the first deflection unit and the rectangular illumination area of ​​the second wavelength deflected and scanned by the second deflection unit onto a reflective light modulation device; and

[0321] A projection lens projects the image light output by the reflective light modulation device,

[0322] The first integrator illumination system and the second integrator illumination system share a light rod, and the plurality of laser beams transmitted from the light diffusion surface are incident on the light rod.

[0323] The first integrator illumination system includes: a separation device for separating the laser beam of the first wavelength from the plurality of laser beams emitted from the light rod; and a relay lens for relaying an image of the emission surface of the light rod.

[0324] The second integrator illumination system includes: a separator for separating the laser beam having the second wavelength from the plurality of laser beams emitted from the light rod; and a relay lens for relaying an image on the emission surface of the light rod.

[0325] [Structure 17]

[0326] The projection display device according to Structure 16 is characterized in that:

[0327] The light diffusing device can dynamically change the positions of the irradiation spots of the plurality of laser beams on the light diffusing surface by moving the light diffusing surface.

[0328] [Structure 18]

[0329] The projection display device according to structure 16 or 17 is characterized in that

[0330] The light diffuser includes the light diffuser surface provided along a circumference centered on a rotation axis, and the light diffuser surface is rotatable about the rotation axis.

Claims

1. A projection display device, characterized in that: have: a first collimating lens for collimating a plurality of laser beams output from a plurality of semiconductor lasers emitting light at a first wavelength; a first condensing lens, for focusing the multiple laser beams collimated by the first collimating lens; a second collimating lens for collimating a plurality of laser beams output from a plurality of semiconductor lasers emitting light at a second wavelength; a second condensing lens, for focusing the multiple laser beams collimated by the second collimating lens; a light diffuser having a light diffusing surface having an area larger than an irradiation spot of the laser beam of the first wavelength focused by the first condensing lens and an irradiation spot of the laser beam of the second wavelength focused by the second condensing lens; a first integrator illumination system for superimposing the laser beams of the first wavelength diffused by the light diffusion surface to form a rectangular irradiation area of ​​the first wavelength; a second integrator illumination system for superimposing the laser beams of the second wavelength diffused by the light diffusion surface to form a rectangular irradiation area of ​​the second wavelength; a first deflection unit arranged at a position closer to the first integrator illumination system than a position where the rectangular illumination area of ​​the first wavelength is formed by the first integrator illumination system; a second deflection unit arranged at a position closer to the second integrator illumination system than a position where the second integrator illumination system forms a rectangular illumination area of ​​the second wavelength; a projection optical system that enlarges and projects the rectangular illumination area of ​​the first wavelength deflected and scanned by the first deflection unit and the rectangular illumination area of ​​the second wavelength deflected and scanned by the second deflection unit onto a reflective light modulation device; and The projection lens projects the image light output by the reflective light modulation device.

2. The projection display device according to claim 1, wherein The light diffuser can dynamically change the position of the irradiation spot of the laser beam with the first wavelength and the position of the irradiation spot of the laser beam with the second wavelength on the light diffuser surface by moving the light diffuser surface.

3. The projection display device according to claim 1, wherein: The light diffuser includes the light diffuser surface provided along a circumference centered on a rotation axis, and the light diffuser surface is rotatable about the rotation axis.

4. The projection display device according to claim 1, wherein: The light diffusion device includes a light-transmitting substrate provided with the light diffusion surface, and a mechanism for rotating, moving in a curved line, or moving in a straight line the substrate.

5. The projection display device according to any one of claims 1 to 4, characterized in that: The light diffuser includes a first diffusion region irradiated by a laser beam having a first wavelength and a second diffusion region irradiated by a laser beam having a second wavelength. The first wavelength is longer than the second wavelength, and the diffusion capability of the first diffusion region is smaller than the diffusion capability of the second diffusion region.

6. The projection display device according to any one of claims 1 to 4, characterized in that: The light diffusion device includes a first diffusion region irradiated with the laser beam of the first wavelength and a second diffusion region irradiated with the laser beam of the second wavelength. The number of semiconductor lasers emitting light at the first wavelength is greater than the number of semiconductor lasers emitting light at the second wavelength, and the diffusion capability of the first diffusion region is smaller than the diffusion capability of the second diffusion region.

7. The projection display device according to any one of claims 1 to 4, characterized in that: Each of the first deflecting unit and the second deflecting unit includes an optical surface rotatable about a rotation axis and arranged along a circumference centered about the rotation axis. The optical surface is configured so that the inclination angle relative to the rotation axis changes along the circumference. The tilt angle is configured so that when the optical surface is continuously rotated at a constant speed, the laser beam is recursively deflected in a constant direction at a constant deflection speed.

8. The projection display device according to any one of claims 1 to 4, characterized in that: The first deflecting unit and the second deflecting unit are integrated, Each of the first deflecting unit and the second deflecting unit includes an optical surface rotatable about a common rotation axis and arranged along a circumference centered on the rotation axis. The optical surface is configured so that the inclination angle relative to the rotation axis changes along the circumference. The tilt angle is configured so that when the optical surface is continuously rotated at a constant speed, the laser beam is recursively deflected in a constant direction at a constant deflection speed.

9. The projection display device according to any one of claims 1 to 4, characterized in that: The plurality of semiconductor lasers emitting light at the first wavelength are arranged so that the directions of their slow axes and fast axes coincide with each other. The long side direction of the rectangular irradiation area of ​​the first wavelength is the direction of the slow axis, The short side direction of the rectangular irradiation area of ​​the first wavelength is the direction of the fast axis, The first deflection unit deflects and scans a rectangular irradiation area of ​​the first wavelength along the short side direction.

10. The projection display device according to claim 9, characterized in that: The plurality of semiconductor lasers emitting light at the second wavelength are arranged so that the directions of their slow axes and fast axes coincide with each other. The long side direction of the rectangular irradiation area of ​​the second wavelength is the direction of the slow axis, The short side direction of the rectangular irradiation area of ​​the second wavelength is the direction of the fast axis, The second deflection unit deflects and scans the rectangular irradiation area of ​​the second wavelength along the short side direction.

11. The projection display device according to any one of claims 1 to 4, characterized in that: The first integrator illumination system and the second integrator illumination system include a light rod on which the laser light transmitted through the light diffuser enters, and a relay lens for relaying an image on an exit surface of the light rod.

12. The projection display device according to claim 11, wherein: The light rod is a prism made of optical material, or a hollow cylinder with a reflective inner surface.

13. The projection display device according to any one of claims 1 to 4, characterized in that: Any one of the first integrator illumination system, the second integrator illumination system, and the relay optical system includes an anamorphic lens.

14. The projection display device according to any one of claims 1 to 4, characterized in that: The projection optical system comprises: a first transfer optical system for enlarging and transferring the rectangular irradiation area of ​​the first wavelength and the rectangular irradiation area of ​​the second wavelength onto a light diffusion plate; and The second projection optical system enlarges and projects the rectangular illumination area of ​​the first wavelength and the rectangular illumination area of ​​the second wavelength, which are enlarged and projected onto the light diffusion plate, onto the reflective light modulation device.

15. The projection display device according to any one of claims 1 to 4, characterized in that: The device further comprises: a third collimating lens for collimating a plurality of laser beams outputted from a plurality of semiconductor lasers emitting light at a third wavelength; a third integrator illumination system; and a third deflection unit. The plurality of laser beams of the third wavelength collimated by the third collimating lens are condensed by the second condensing lens and focused onto the light diffuser. The laser beams of the third wavelength diffused by the light diffusion surface are superimposed by the third integrator illumination system to form a rectangular irradiation area of ​​the third wavelength. The third deflection unit is arranged at a position closer to the third integrator illumination system than a position where the rectangular illumination area of ​​the third wavelength is formed by the third integrator illumination system. The projection optical system magnifies and projects the rectangular irradiation area of ​​the first wavelength deflected and scanned by the first deflection unit, the rectangular irradiation area of ​​the second wavelength deflected and scanned by the second deflection unit, and the rectangular irradiation area of ​​the third wavelength deflected and scanned by the third deflection unit onto the reflective light modulator.

16. A projection display device, characterized in that: have: a first collimating lens for collimating a plurality of laser beams output from a plurality of semiconductor lasers emitting light at a first wavelength; a second collimating lens for collimating a plurality of laser beams output from a plurality of semiconductor lasers emitting light at a second wavelength; a synthesis unit for superimposing and synthesizing the plurality of laser beams collimated by the first collimating lens and the plurality of laser beams collimated by the second collimating lens; a first condensing lens for focusing the multiple laser beams synthesized by the synthesis unit; a light diffusion device having a light diffusion surface, wherein the area of ​​the light diffusion surface is larger than the irradiation spot of the plurality of laser beams focused by the first condensing lens; a first integrator illumination system for superimposing the laser beams of the first wavelength among the plurality of laser beams diffused by the light diffusion surface to form a rectangular irradiation area of ​​the first wavelength; a second integrator illumination system for superimposing the laser beams of the second wavelength among the plurality of laser beams diffused by the light diffusion surface to form a rectangular irradiation area of ​​the second wavelength; a first deflection unit arranged at a position closer to the first integrator illumination system than a position where the rectangular illumination area of ​​the first wavelength is formed by the first integrator illumination system; a second deflection unit arranged at a position closer to the second integrator illumination system than a position where the second integrator illumination system forms a rectangular illumination area of ​​the second wavelength; a projection optical system that enlarges and projects the rectangular illumination area of ​​the first wavelength deflected and scanned by the first deflection unit and the rectangular illumination area of ​​the second wavelength deflected and scanned by the second deflection unit onto the reflective light modulation device; as well as A projection lens projects the image light output by the reflective light modulation device, The first integrator illumination system and the second integrator illumination system share a light rod, and the plurality of laser beams transmitted from the light diffusion surface are incident on the light rod. The first integrator illumination system includes: a separation device for separating the laser beam of the first wavelength from the plurality of laser beams emitted from the light rod; and a relay lens for relaying an image of the emission surface of the light rod. The second integrator illumination system includes: a separator for separating the laser beam having the second wavelength from the plurality of laser beams emitted from the light rod; and a relay lens for relaying an image on the emission surface of the light rod.

17. The projection display device according to claim 16, wherein: The light diffusing device can dynamically change the positions of the irradiation spots of the plurality of laser beams on the light diffusing surface by moving the light diffusing surface.

18. The projection display device according to claim 16, wherein: The light diffuser includes the light diffuser surface provided along a circumference centered on a rotation axis, and the light diffuser surface is rotatable about the rotation axis.

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