JP4845474B2 - LIGHT SOURCE DEVICE AND VIDEO DISPLAY DEVICE USING LIGHT SOURCE DEVICE - Google Patents

Description

  The present invention relates to a light source device used for a video display device such as a projector, and more particularly to a technique for efficiently collimating light emitted from a solid-state light emitting element such as a light emitting diode or a semiconductor laser and using it in a video display device. It is.

  Conventionally, a light source device using an ultra-high pressure mercury lamp has been used as a light source device for an image display device such as a projector. However, the ultra-high pressure mercury lamp has a problem that its life is short, and the light source device has a longer life. Was demanded. As a solution to this problem, a light source device using a solid light emitting element such as a light emitting diode or a semiconductor laser can be considered.

In a conventional light source device using a solid light emitting element, a solid light emitting element and a concave reflector portion arranged so as to surround the light emitting element are sealed with resin, and the lens and the lens are formed with resin on the front surface of the solid light emitting element. It has a configuration in which a total reflection region for reflecting light that is not incident is integrally formed, and controls the radiation intensity distribution of the emitted light from the solid state light emitting device to some extent.

Japanese Patent Laying-Open No. 2002-94129 (paragraphs 0082 to 0083, FIG. 12) Japanese Patent Laid-Open No. 2002-134794 (paragraphs 0027 to 0031, FIG. 2)

However, in order to use the light source device as a light source for a projector, the light beam emitted from the light source device needs to be approximately parallel so that the divergence angle is within about ± 2 to 3 degrees. A conventional light source device using a solid state light emitting element is a surface light emitter, because the lens and the total reflection region are integrally formed so that a lens surface cannot be formed on the light emitting element side, and the lens shape is greatly limited. There has been a problem that the light emitted from the solid state light emitting element cannot be converted into a highly parallel light beam that can be used in the projector light source device.

The present invention has been made to solve such problems, and can efficiently convert light emitted from a solid-state light emitting device into substantially parallel light, and can be used as an illumination light source for a video display device such as a projector. The object is to obtain a device.

A light source apparatus according to the present invention according to the first solving means is provided with a solid-state light-emitting device, the total reflection on the optical mirror and the optical mirror flat you act as a total reflection surface of light of the solid state light emitting devices a first optical element possess a concave reflecting surface that emits a substantially parallel light reflected by the light they are integrally formed, is installed in front of the first optical element, the light from the solid state light emitting devices A second optical element having a central lens region that emits as direct incident light and substantially parallel light, and the first optical element has a conical shape with the solid light emitting element as a vertex, the solid light emitting element side A penetrating space penetrating from the second optical element to the central lens region side, and an incident interface that covers the solid light emitting element in a region other than the penetrating space and into which light from the solid light emitting element is incident. And having the second optical element Has an annular region that surrounds the periphery of the central lens region and allows light reflected by the concave reflecting surface to pass therethrough, and the central lens region occupies the inside of the annular region. is there. In this light source device, the light incident on the first optical element out of the light emitted from the solid state light emitting element is converted into substantially parallel light using the optical mirror surface and the concave reflecting surface, and directly incident on the second optical element. The light is made to be substantially parallel light using the central lens region.

The light source device according to the present invention according to the second solving means includes a solid-state light-emitting element, and is a planar optical element that is installed in front of the solid-state light-emitting element and functions as a total reflection surface of light of the solid-state light-emitting element. possess a concave reflecting surface for reflecting the total reflection light at the specific mirror and said optical mirror surface thereof is installed in front of the first optical element, the first optical element which is integrally formed, said solid state light substantially incident reflected light around the central lens region for emitting light from the device as a direct incident light to substantially parallel light central lens region-out winding up in the annular, concave reflecting surface of the first optical element A second optical element having two lens areas of an outer peripheral lens area that emits as parallel light , the first optical element having a conical shape having the solid light emitting element as a vertex, the solid light emitting element side To the second optical element A through space penetrating toward the central lens region, and an incident interface that covers the solid state light emitting device in a region other than the through space and is incident with light from the solid state light emitting device, and the central lens region Occupies the inside of the outer peripheral lens region. In this light source device, light incident on the first optical element out of the light from the solid light emitting element is substantially parallel using the optical mirror surface, the concave reflecting surface, and the outer peripheral lens region of the second optical element. The light that is converted into light and directly incident on the second optical element is converted into substantially parallel light using the central lens region.

According to the light source device of the present invention, the central lens region of the second optical element can be a double-sided lens, which increases the optical working surface as compared with the case where only a single-sided lens is used as the optical element. Thus, there is an effect that it is possible to efficiently obtain outgoing light with high parallelism and low aberration suitable for an illumination light source for a projector apparatus.

Further, according to the light source device of the present invention, the second optical element has the central lens region and the outer lens region, so that not only the light directly emitted from the solid light emitting element but also the concave reflecting surface of the first optical element. Since the optical action surface can be increased even with respect to the light reflected at, there is an effect that outgoing light with higher parallelism and less aberration can be efficiently obtained with respect to the entire light region.

Embodiment 1 FIG.
A light source device according to Embodiment 1 of the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view of a light source device according to Embodiment 1 of the present invention. The light source device of the present invention includes a solid light emitting element 1, a first optical element 2 disposed in front of the solid light emitting element 1, and a second optical element 3 disposed in front of the first optical element 2. ing. The first optical element 2 is formed by integrally forming a parabolic concave reflecting surface 2a symmetrical to the optical axis and a planar optical mirror surface 2b. The parabolic surface of the concave reflecting surface 2a is provided with a mirror coat, and acts as a parabolic reflector. The optical mirror surface 2b acts as a total reflection surface on which light rays traveling in the first optical element 2 are totally reflected at the interface of the optical mirror surface 2b. The solid-state light-emitting element 1, the concave reflecting surface 2a, and the optical mirror surface 2b are positioned so that the position of the solid-state light-emitting element 1 and the focal point 2c of the parabolic surface of the concave reflecting surface 2a are substantially conjugate with respect to the optical mirror surface 2b. It is arranged to become.

  In addition, a conical space 2d having a solid light emitting element 1 as a vertex penetrating from the solid light emitting element 1 side to the second optical element 3 side is opened at a central portion of the first optical element 2. The half of the apex angle α of the cone is equal to or larger than the critical angle θ at the interface between the first optical element 2 and air, that is, the optical mirror surface 2b. Further, the first optical element 2 is provided with a spherical interface 2 e centering on the solid light emitting element 1 so as to cover the solid light emitting element 1.

  On the other hand, the center of the second optical element 3 is a lens area 3a having a lens action, the lens surface of the lens area 3a is formed of a double-sided aspheric surface, and the focal point of the lens area 3a is approximately the position of the solid light emitting element 1. Is almost identical. Further, the diameter D of the lens region 3a satisfies the following equation using c as the apex curvature of the paraboloid of the concave reflecting surface 2a and the critical angle θ described above. The meaning of the diameter D will be described later.

The solid-state light emitting device 1 has an emission characteristic as a so-called surface light source. Since the optical system including the surface light source has a difficulty in handling the light source as a single point light source, the characteristics of the optical system including the surface light source will be described here. FIGS. 2A and 2B are explanatory diagrams showing the path of the light beam when (a) the light emitted from the point light source passes through the single-sided lens and (b) when the light emitted from the surface light source passes through the single-sided lens. The surface light source can be regarded as a surface distribution of a plurality of point light sources. However, in the figure, in order to avoid complication, the surface light sources are approximated by two point light sources. As can be seen from FIG. 2, even if a single-sided lens that can collimate the light emitted from the point light source is used, the entire light emitted from the surface light source cannot be completely collimated. FIG. 3 shows a case in which the outgoing light included in the same divergence angle out of the outgoing light from the surface light source is converted into substantially parallel light using lenses having different lens diameters. As can be seen from FIG. 3, it is understood that substantially parallel light with higher parallelism can be obtained by using a lens having a large lens diameter.

In the figure for explaining the operation of the present invention, only the ray path when the solid-state light-emitting element 1 as a surface light source is regarded as one point light source is shown in order to avoid making the figure complicated. In understanding the optical action of the invention, it is necessary to consider that the solid-state light-emitting element 1 is a surface light source in consideration of the special characteristics of the surface light source.

Next, the operation of the present invention having the above-described configuration will be described with reference to FIG. 4, focusing on the effect on the light emitted from the solid state light emitting device 1. FIG. 4 shows in detail the path of the light beam in the light source device shown in FIG. Accordingly, the configuration of the light source device is the same as that of the light source device of FIG. As described above, the light emitted from the solid light emitting element 1 needs to be regarded as light emitted from the surface light source. However, in FIG. 4, only the path of the light beam when the solid light emitting element 1 is regarded as one point light source. Is shown.

The light emitted from the solid-state light emitting element 1 travels in a hemispherical manner centered on the optical axis, but the first optical element 2 has a conical space in which the half of the apex angle is α. Since 2d is provided, light having a divergence angle with respect to the optical axis of the light emitted from the solid-state light emitting element 1 passes through the conical space 2d and directly enters the lens region 3a of the second optical element 3. Incident. Then, the light incident on the lens region 3a is subjected to the lens action of the lens region 3a, is converted into substantially parallel light, and is emitted.

  On the other hand, light having a divergence angle of α or more out of the light emitted from the solid-state light emitting element 1 enters the first optical element 2 via the spherical interface 2 e of the first optical element 2. At this time, since the solid-state light emitting element 1 is located at the spherical center of the spherical interface 2e, the light incident on the first optical element 2 hardly changes the traveling direction of the light beam at the spherical interface 2e. The light enters the first optical element 2. Then, almost all of the light that has entered the first optical element 2 reaches the optical mirror surface 2b with an incident angle of α or more, and is totally totally reflected by the optical mirror surface 2b to be a concave reflecting surface. Head for 2a. Here, since the arrangement position of the solid light emitting element 1 and the focal point 2c of the parabolic surface of the concave reflecting surface 2a are in a substantially conjugate positional relationship with respect to the optical mirror surface 2, the light is emitted from the solid light emitting element 1 and is reflected by the optical mirror surface 2b. As shown in FIG. 4, since the totally reflected light has the same ray direction as the light emitted from the light source placed at the focal point 2c of the parabolic surface of the concave reflecting surface 2a, it is reflected by the concave reflecting surface 2a. After that, it becomes substantially parallel light with a high degree of parallelism and is emitted to the outside of the first optical element 2.

In this way, all the emitted light from the solid state light emitting device 1 becomes substantially parallel light with a high degree of parallelism and is emitted to the outside of the light source device. The value of the diameter D of the lens region 3a shown in the above (Equation 1) is substantially the same as the diameter of the inner portion of the annular region through which substantially parallel light reflected by the concave reflecting surface 2a passes. It was derived to be equal. Therefore, when the diameter D of the lens region 3a satisfies (Equation 1), the light does not pass between the region of the emitted light transmitted through the lens region 3a and the region of the emitted light reflected by the concave reflecting surface 2a. An area can be prevented from being generated. Thereby, the whole emitted light from the light source device of the present invention can have a continuous and smooth intensity distribution.

As described above, according to the present invention, since the second optical element 3 having the lens region is independent of the first optical element 2, the shape and size of the lens region 3a of the second optical element 3 are the same. Can be set freely. Thereby, since the lens area 3a can be a double-sided lens and the lens area 3a can be enlarged, the light emitted from the solid-state light emitting element 1 which is a surface light source has a small aberration and is parallel using more optical action surfaces. It becomes possible to efficiently convert into substantially parallel light having a high degree.

  Furthermore, since the diameter of the lens region 3a of the second optical element 3 is set to occupy almost the entire inner region of the annular region through which the light reflected by the concave reflecting surface 2a passes, the smooth intensity that is continuous over the entire emitted light. A substantially parallel light flux having a distribution can be obtained.

Furthermore, since the light of the solid-state light emitting element 1 incident on the first optical element 2 does not change its light beam direction at the interface 2e on the spherical surface, almost all the light incident on the first optical element 2 is made substantially parallel. As a result, the light utilization efficiency can be increased. In addition, light emitted directly from the solid-state light emitting element 1 and directed directly to the second optical element 3 passes through the conical space 2d in the first optical element 2, so that the second optical element does not lose light. Since it can enter into the element 3, the utilization efficiency of light can be improved.

Further, since the first optical element 2 and the second optical element 3 are configured independently, the optical mirror surface 2b of the first optical element 2 acting as a total reflection surface is simply formed as a flat surface. Since it can be manufactured without requiring special processing, the light source device can be manufactured at a lower cost.

In addition, since the solid-state light-emitting element 1, the first optical element 2, and the second optical element 3 are independent from each other, it is easy to replace individual components such as the solid-state light-emitting element, which contributes to the maintenance cost of the light source device. There is also an advantage that the cost can be reduced.

  In the present embodiment, the shape of the concave reflecting surface 2a is a parabolic surface, but a shape other than the parabolic surface may be used. In addition, the shape of the lens region 3a is a double-sided aspheric surface, but it may be configured by combining a spherical surface, a flat surface, and the like. Further, the second optical element 3 may be composed of two or more lenses.

Even in such various modified configurations, the arrangement positions of the solid-state light-emitting element 1, the first optical element 2, and the second optical element 3, the optical mirror surface 2 b and the concave reflecting surface of the first optical element 2 are also included. The shape of 2a and the shape and size of the lens region 3a of the second optical element 3 can be adjusted by the same method as described above.

Embodiment 2. FIG.
FIG. 5 is a cross-sectional view of a light source device according to Embodiment 2 of the present invention. A light source device according to Embodiment 2 will be described with reference to the drawings. The light source device of the present invention includes a solid light emitting element 11, a first optical element 12 disposed in front of the solid light emitting element 11, and a second optical element 13 disposed in front of the first optical element 12. ing. The first optical element 12 has an elliptical shape symmetric with respect to the optical axis, and is formed by integrally forming a concave reflecting surface 12a acting as an elliptical reflector and a planar optical mirror surface 12b. The optical mirror surface 12b acts as a total reflection surface where the light beam traveling in the first optical element 12 is totally reflected at the interface of the optical mirror surface 12b. The solid light-emitting element 11, the concave reflecting surface 12a, and the optical mirror surface 12b are a focal point 12c (first focus) on the solid light-emitting element 11 side of the two focal points of the position of the solid light-emitting element 11 and the elliptical surface of the concave reflecting surface 12a. 1 focal point) is arranged so as to have a substantially conjugate positional relationship with respect to the optical mirror surface 12b. As in the first embodiment, the central portion of the first optical element 12 has a conical space penetrating from the solid light emitting element 11 side to the second optical element 13 side, and the solid light emitting element 11 is the center. And a spherical interface.

The second optical element 13 includes a central lens region 13a located at the center thereof, and an outer peripheral lens region 13b that surrounds the periphery of the central lens region in an annular shape. The central lens region 13a is a lens that acts as a double-sided convex lens, and the outer lens region 13b is a lens that acts as a double-sided concave lens. The diameter of the central lens region 13a is such that it almost occupies the entire inner region of the annular region through which the light reflected by the concave reflecting surface 12a passes. Further, the lens in the central lens region 13a is composed of double-sided aspherical surfaces, and is shaped and arranged so that light emitted from the solid-state light emitting element 11 has an angle with the optical axis within α is approximately parallel. The focal point is approximately coincident with the position of the solid state light emitting device 11. Α is a value equal to or larger than the critical angle at the interface between the first optical element 12 and air, that is, the optical mirror surface 12b. The outer peripheral lens region 13b is arranged so that almost all of the light reflected by the concave reflecting surface 12a passes and receives the action of the concave lens.

Next, the operation of the present invention having the above-described configuration will be described with reference to FIG. 6 while focusing on the action on the light emitted from the solid state light emitting device 11. FIG. 6 shows in detail the path of the light beam in the light source device shown in FIG. Therefore, the configuration of the light source device is the same as that of the light source device of FIG.

Of the light emitted from the solid-state light emitting element 11, the light having a divergence angle with respect to the optical axis within about α is a conical space opened in the center of the first optical element 12 as in the first embodiment. And enters the central lens region 13a of the second optical element 13 directly. Then, the light incident on the central lens region 13a is subjected to a convex lens action, is converted into a substantially parallel light, and is emitted.

On the other hand, of the light emitted from the solid state light emitting element 11, light having a divergence angle of approximately α or more enters the first optical element 12 from the spherical interface of the first optical element 12, and enters the optical mirror surface 12b. This is the same as in the first embodiment in that almost all of the light is totally reflected, travels toward the concave reflecting surface 12a, and is reflected again by the concave reflecting surface 12a. Here, in Embodiment 2, the shape of the concave reflecting surface 12a is an elliptical surface, and the position of the solid-state light emitting element 11 and the first focal point 12c of the elliptical surface are in a substantially conjugate positional relationship with respect to the optical mirror surface 12b. Therefore, the light after being totally reflected by the optical mirror surface 12b has the same light beam direction as the light emitted from the light source placed at the first focal point 12c of the elliptical surface. For this reason, after the light incident on the concave reflecting surface 12a is reflected by the concave reflecting surface 12a, it is emitted from the first optical element 12 while being condensed toward the other focal point (second focal point) of the elliptical surface. The light emitted from the first optical element 12 is incident on the outer lens area 13b of the second optical element 13, and is converted into a substantially parallel light by receiving the concave lens action of the outer lens area 13b. To the outside.

As described above, according to the present invention, the second optical element 13 has two lens areas, the central lens area 13a and the outer lens area 13b, and the reflected light from the concave reflecting surface 12a of the first optical element 12. Pass through the outer lens region 13b, so that the light that has entered the first optical element 12 out of the light emitted from the solid-state light emitting element 11 has two optical functions of the concave reflecting surface 12a and the outer lens region 13b. The plane will be approximately parallel. For this reason, as compared with the case of the first embodiment, since the acting optical working surface is increased, a substantially parallel light beam with less aberration and higher parallelism can be efficiently obtained. Moreover, since the shape of the concave reflecting surface 12a can be set more freely by providing the outer peripheral lens region 13b, the light-incorporating light flux into the concave reflecting surface 12a is increased, and the light utilization efficiency can be improved.

  Furthermore, since the diameter of the central lens region 13a of the second optical element 13 is set to occupy almost the entire inner area of the annular region through which the light reflected by the concave reflecting surface 12a passes, the entire emitted light is continuous and smooth. A substantially parallel light beam having an intensity distribution is obtained.

Furthermore, since the light of the solid state light emitting element 11 incident on the first optical element 12 does not change its light direction at the interface on the spherical surface, almost all of the light incident on the first optical element 12 can be made substantially parallel. Therefore, the light use efficiency can be increased. Moreover, since the light which goes directly to the 2nd optical element 13 among the emitted light of the solid light emitting element 11 passes the conical space in the 1st optical element 12, it is 2nd optical element without the loss of light. 13, the light utilization efficiency can be increased.

In the present embodiment, the concave reflecting surface 12a has an elliptical shape, but a shape other than the elliptical surface may be used. In addition, the shape of the lens region 13a is a double-sided aspheric surface, but a configuration in which a spherical surface, a flat surface, or the like is combined may be used. Further, the second optical element 13 may be composed of two or more lenses.

Embodiment 3 FIG.
An image display device can be formed using the light source device described in Embodiment 1 or 2. FIG. 7 is a diagram illustrating a configuration of a video display device using the light source device described in the first embodiment. Hereinafter, the video display apparatus according to the present embodiment will be described with reference to FIG. Each of the light source devices 20r, 20g, and 20b is the light source device shown in the first embodiment, and includes a solid light emitting element, a first optical element, and a second optical element. However, the solid-state light emitting element is different for each light source device, the light source device 20r includes a solid light-emitting element 21r that emits red light, the light source device 20g includes a solid-state light emitting element 21g that emits green light, and the light source device 20b includes blue light. The solid-state light emitting device 21b that emits light is provided.

First, the path | route of the light radiate | emitted from each solid light emitting element is demonstrated. As described in the first embodiment, the red light emitted from the solid state light emitting element 21r of the light source device 20r is subjected to the action of the first optical element and the second optical element to become a substantially parallel light beam, and the light source device 20r. It is emitted to the outside. Similarly, the light source device 20g emits green light having a substantially parallel light beam, and the light source device 20b emits blue light having a substantially parallel light beam.

The substantially parallel red light emitted from the light source device 20r is bent 90 degrees by the half mirror 22r, passes through the half mirror 22g, is reflected by the half mirror 22b, and is guided to the fly-eye lens 23. Here, the half mirror 22r reflects red light, the half mirror 22g transmits red light and reflects green light, and the half mirror 22b transmits blue light and reflects green light and red light. -It has reflection characteristics. The substantially parallel green light emitted from the light source device 20 g is reflected by the half mirror 22 g, bent in the traveling direction by 90 degrees, reflected again by the half mirror 22 b, and guided to the fly-eye lens 23. The substantially parallel blue light emitted from the light source device 20 b passes through the half mirror 22 b and is guided to the fly-eye lens 23.

The light guided to the fly-eye lens 23 is multi-divided on the entrance surface of the fly-eye lens 23, forms an image on the exit surface of the fly-eye lens 23, and a condenser lens 24 having a function of condensing the light. The light valve 26 is illuminated uniformly through a field lens 25 that forms an image on the light exit surface of the lens 23 on the light valve 26. The light valve 26 is a reflection type light valve, and spatially modulates each color light illuminated on the light valve 26 by time division control based on a light valve drive signal 27a output from a control device 27 described later. Then, the spatially modulated light enters the projection lens 29 via the total reflection prism 28 and is enlarged and projected to display an image.

The light valve 26 and the solid state light emitting devices 21r, 21g, and 21b are controlled so as to perform a linked operation. Next, the control method will be described. First, the video signal processing device 30 creates a signal corresponding to each color component of red, green, and blue from the video signal 31 inputted from the outside, and writes it in a memory (not shown) in the video signal processing device 30 in units of video frames. . Thereafter, the video signal processing device 30 sequentially switches within the video frame and outputs the signal of each color component in the memory as the RGB signal 30a. Based on the RGB signal 30a, the control device 27 controls the LED drive signals 27r, 27g, and 27b that control the solid-state light emitting elements 21r, 21g, and 21b and the light valve drive signal 27a that drives the light valve 26, respectively. Specifically, the LED drive signals 27r, 27g, and 27b are driven so that the solid state light emitting elements 21r, 21g, and 21b are sequentially turned on in a time-sharing manner, whereby light of each color sequentially irradiates the light valve 26. The light valve drive signal 27a is controlled in synchronization with the LED drive signals 27r, 27g, and 27b, so that the light valve 26 is synchronized with the lighting timings of the solid-state light emitting elements 21r, 21g, and 21b, and the spatial components of the respective color components. Modulate. In this way, the light valve 26 and the solid state light emitting devices 21r, 21g, and 21b can be linked, and images of red, blue, and green are sequentially switched and projected within the video frame to be viewed as a color image. Can do.

  As described above, since the light source device shown in the first embodiment is used as the light source devices 20r, 20g, and 20b used in the video display device, the light emitted from the light source devices 20r, 20g, and 20b has small aberration and This results in a substantially parallel light beam with a high degree of parallelism, which can reduce the loss of light in the reflecting and transmitting actions of the half mirrors 22r, 22g, and 22b, and also increases the transmittance of the fly-eye lens 23. Therefore, there is an effect that the light use efficiency of the entire image display apparatus is increased, and a brighter image can be obtained.

In addition, since the three primary light emitting elements 21r, 21g, and 21b of red, blue, and green are controlled to be turned on in a time-sharing manner, the power required for driving the solid light emitting elements 21r, 21g, and 21b is reduced. This can save power. In addition, by appropriately selecting the wavelengths of the solid-state light emitting elements 21r, 21g, and 21b for the respective colors, it is possible to widen the color range that is reproduced by combining light, and it is possible to obtain an image with good color reproducibility.

Embodiment 4 FIG.
FIG. 8 shows a configuration of another type of video display device using the light source device shown in the first embodiment. In FIG. 8, the same parts as those in FIG. Hereinafter, the video display apparatus according to Embodiment 4 will be described with reference to FIG.

The light source devices 20r, 20g, and 20b are the light source devices shown in Embodiment 1 including the red, green, and blue solid light emitting elements 21r, 21g, and 21b, respectively. First, the path | route of the light radiate | emitted from each solid light emitting element is demonstrated. The red light emitted from the solid light emitting element 21r of the light source device 20r is emitted from the light source device 20r as a substantially parallel light beam by the action of the first optical element and the second optical element. The substantially parallel red light emitted from the light source device 20r is incident on the fly-eye lens 23r and the light intensity distribution is made uniform, and then the light valve 26r is uniformly illuminated via the condenser lens 24r and the field lens 25r. To do. The light valve 26 r is a transmissive light valve, and the red light spatially modulated by the light valve 26 r is incident on the combining prism 40. Similarly, substantially parallel green light and blue light emitted from the light source devices 20g and 20b also pass through the fly-eye lenses 23g and 23b, the condenser lenses 24g and 24b, and the field lenses 24g and 24b, respectively, and the light valves 26g and 26b. Irradiate uniformly. The green light and the blue light spatially modulated by the light valves 26g and 26b enter the combining prism 40. After the three colors of red, green, and blue light are combined by the combining prism 40, the projection lens 29 is combined. The image is displayed by being incident on and enlarged and projected.

Next, the control operation will be described. The video signal processing device 30 creates a signal corresponding to each color component of red, green, and blue from the video signal 31 input from the outside, and writes it in a memory (not shown) in the video signal processing device 30 in units of video frames. . Thereafter, the video signal processing device 30 sequentially switches within the video frame and outputs the signal of each color component in the memory as the RGB signal 30a. The control device 41 drives the LED drive signals 41r, 41g, 41b so that the solid state light emitting elements 21r, 21g, 21b are always lit, and controls the light valve drive signals 42r, 42g, 42b based on the RGB signal 30a. Thus, the light valves 26r, 26g, and 26b can apply spatial modulation to each color light in synchronization with the video signal 31.

As described above, since the light source device shown in the first embodiment is used as the light source devices 20r, 20g, and 20b used in the video display device, the same effect as that of the video display device described in the third embodiment is obtained. be able to.

In the third to fourth embodiments, the case where one light source device is used as the light source for each color has been described. However, the present invention is not limited to this, and the light source device is selected according to the light intensity of the solid state light emitting element in the light source device. Two or more may be used. In the third to fourth embodiments, the light source device according to the first embodiment has been described. However, the present invention is not limited to this, and the same effect can be obtained if the video display device uses the light source device according to the present invention. Have. Further, the light valve is not limited to that used in the description of the embodiment, and any other light valve may be used as long as it has a function of spatially modulating light.

It is sectional drawing of the light source device by Embodiment 1 of this invention. It is explanatory drawing which compares the characteristic of a point light source and a surface light source. It is explanatory drawing which shows the characteristic of a surface light source. It is explanatory drawing of operation | movement of the light source device by Embodiment 1 of this invention. It is sectional drawing of the light source device by Embodiment 2 of this invention. It is explanatory drawing of operation | movement of the light source device by Embodiment 2 of this invention. It is a figure which shows the structure of the video display apparatus by Embodiment 3 of this invention. It is a figure which shows the structure of the video display apparatus by Embodiment 4 of this invention.

Explanation of symbols

1, 11, 21 r, 21 g, 21 b... Solid light emitting element 2, 12... First optical element 2 a, 12 a... Concave reflecting surface 2 b, 12 b. 12c ... Focus 3, 13 of the concave reflecting surface ... Second optical element 3a ... Lens area 13a of the second optical element ... Central lens area 13b of the second optical element .... Peripheral lens area of second optical element

Claims (10)

A solid state light emitting device;
A planar optical mirror surface installed in front of the solid state light emitting element and acting as a total reflection surface of the light of the solid state light emitting element, and a concave reflection that reflects the total reflection light on the optical mirror surface and emits it as substantially parallel light A first optical element integrally formed with the surface;
A second optical element installed in front of the first optical element and having a central lens region that emits light from the solid-state light emitting element as direct incident light and substantially parallel light ;
The first optical element includes:
A penetrating space penetrating from the solid light emitting element side to the central lens region side of the second optical element, having a conical shape with the solid light emitting element as a vertex;
An incident interface that covers the solid-state light-emitting element in a region other than the through space and is incident with light from the solid-state light-emitting element;
Have
The second optical element has an annular region that surrounds the periphery of the central lens region in an annular shape and allows light reflected by the concave reflecting surface to pass through.
Said central lens region, a light source device according to claim Rukoto occupy the interior of the annular region. The light source device according to claim 1, wherein the central lens region of said second optical element is a double-sided lens. The incident interface is a spherical interface centered on the solid state light emitting device ,
The optical mirror surface totally reflects light incident on the first optical element via the incident interface in the direction of the concave reflecting surface, and reflects the light reflected by the concave reflecting surface and emitted as substantially parallel light. The light source device according to claim 1 or 2, wherein the light source device transmits light in a direction of the annular region . The light source device according to claim 1 , wherein the solid-state light emitting element has a planar light emitting region that emits light toward the incident interface and the through space . Concave reflecting surface of the first optical element is a paraboloid,
Focal point of the solid the paraboloid and the light emitting element is in a positional relationship of substantially conjugate with respect to the optical mirror of the first optical element,
5. The light source device according to claim 1, wherein the central lens region of the second optical element is a convex lens. 6. A solid state light emitting device;
A flat optical mirror surface that is installed in front of the solid light emitting element and functions as a total reflection surface of light of the solid light emitting element and a concave reflection surface that reflects the total reflection light on the optical mirror surface are integrally formed. A first optical element;
A central lens region that is installed in front of the first optical element and emits light from the solid state light emitting device as direct incident light and substantially parallel light, and surrounding the central lens region in an annular shape, A second optical element having two lens regions of an outer peripheral lens region that receives reflected light from the concave reflecting surface of the optical element and emits the light as substantially parallel light ;
The first optical element includes:
A penetrating space penetrating from the solid light emitting element side to the central lens region side of the second optical element, having a conical shape with the solid light emitting element as a vertex;
An incident interface that covers the solid-state light-emitting element in a region other than the through space and is incident with light from the solid-state light-emitting element;
Have
Said central lens region, a light source device according to claim Rukoto occupy the interior of the peripheral lens area. The light source device according to claim 6, wherein the central lens region and the peripheral lens area of the second optical element is characterized in that it is a double-sided lens. The incident interface is a spherical interface centered on the solid state light emitting device ,
The optical mirror surface totally reflects light incident on the first optical element through the incident interface toward the concave reflecting surface, and reflects light from the concave reflecting surface toward the outer lens region. The light source device according to claim 6 or 7, wherein the light source device transmits light. The concave reflecting surface of the first optical element is ellipsoidal,
The focus of the solid state light emitting element side of the two foci of the elliptical surface and the solid-state light-emitting element is in a positional relationship of substantially conjugate with respect to the optical mirror surface of the first optical element,
Of the lens region of said second optical element, wherein the central lens region is convex, the peripheral lens area light source device according to claim 6, wherein 8 to be a concave lens. Image display device using the light source of the light source apparatus according to any one of claims 1 to 9.

Images