JP2016154145A - Luminaire, electronic equipment and projection type display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a luminaire having high light-emitting efficiency without deteriorating discoloration of pigment or dye.SOLUTION: A luminaire 100 includes: a light-emitting element having a solid light source for emitting excitation light ExL and a phosphor 103 irradiated with the excitation light ExL; a light conversion element configured to convert part of radiation light from the light-emitting element to parallel light; and an optical filter element configured to transmit long wavelength light out of the parallel light, and reflect a short wavelength light. Since the short wavelength light promoting discoloration deterioration to the parallel light is partially removed, provided can be a luminaire 100 configured to emit light hardly deteriorating discoloration of pigment or dye.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an illumination device using a light emitting element, an electronic apparatus including the illumination device, and a projection display device.

  A projection display device called a projector is an electronic device that irradiates light to a transmissive electro-optical device or a reflective electro-optical device and projects the transmitted light or reflected light modulated by these electro-optical devices onto a screen. . This is configured so that light emitted from a light source is condensed and incident on an electro-optical device, and transmitted light or reflected light modulated according to an electric signal is enlarged and projected onto a screen through a projection lens. It has the advantage of displaying a large screen. A liquid crystal device is known as an electro-optical device used in such an electronic apparatus, and an image is formed by using dielectric anisotropy of liquid crystal and optical rotation of light in a liquid crystal layer.

  An example of a projector using a liquid crystal device is described in Patent Document 1. The liquid crystal device has a plurality of pixels, and a color filter of any color of red, green, and blue is provided for each pixel. A projector often uses a metal halide lamp as a light source, and the liquid crystal device is irradiated with intense light from the metal halide lamp. For this reason, these color filters are subject to deterioration such as fading due to the intense light irradiated. Therefore, for the purpose of improving the light resistance of the color filter, in Patent Document 1, an inorganic pigment is used for a color filter having a poor light resistance, and an organic pigment is used for a color filter having a relatively strong light resistance. doing.

JP-A-8-338992

  However, there is a problem that it is actually difficult to change the type of pigment of the color filter for each pixel. In particular, in a projector application where high definition of an image and miniaturization of an electro-optical device are progressing, the pixel size becomes very small. Therefore, the method described in Patent Document 1 cannot be a practical solution. It was. In addition, there is a problem that power consumption is increased in order to increase the light of the light source. In other words, the conventional electronic device has a problem that power consumption is large and, in addition, practical light resistance of the color filter is not obtained.

  SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following forms or application examples.

Application Example 1 An illumination apparatus according to this application example includes at least one of a light emitting element having a solid light source that emits excitation light and a phosphor irradiated with the excitation light, and light (radiated light) emitted from the light emitting element. A light conversion element that converts the light into substantially parallel light (parallel light), and an optical filter that transmits light having a wavelength longer than the cutoff wavelength and reflects light having a wavelength shorter than the cutoff wavelength. And an element.
It is mainly short-wavelength light such as blue light and ultraviolet light that causes color deterioration of pigments and dyes used in color filters and paintings. On the other hand, the light emitted from the light emitting element (radiated light) is a mixture of excitation light having a short wavelength component and fluorescence having a long wavelength component emitted from a phosphor. According to this configuration, since the short wavelength light that promotes the fading deterioration is partially removed from the parallel light, it is possible to provide an illuminating device that emits light that does not easily cause the fading deterioration of the pigment or the dye.

Application Example 2 In the illumination device according to the application example, it is preferable that the optical filter element reflects at least a part of the excitation light included in the parallel light.
According to this configuration, since the short wavelength light such as a part of the excitation light is partially removed from the parallel light, it is possible to provide an illuminating device that emits light that hardly causes the pigment or dye to fade.

Application Example 3 In the illumination device according to the application example described above, it is preferable that at least a part of the light reflected by the optical filter element is irradiated with a phosphor.
The light reflected by the optical filter element (reflected light) is short wavelength light such as a part of excitation light. According to this configuration, the reflected light (short wavelength light such as a part of the excitation light) irradiates the phosphor again to release the fluorescence, so that even if the excitation light emitted from the solid light source is weakened, the light source is made bright. Can do. That is, the substantial light emission efficiency of the light emitting element can be increased and the power consumption can be suppressed.

Application Example 4 In the illumination device according to the application example described above, when the color temperature of the emitted light is represented by x (K) and the cutoff wavelength is represented by y (nm), the color temperature x and the cutoff wavelength. It is preferable that y satisfies the relationship of y = 0.2048x + 397.18.
The higher the color temperature of the emitted light, the higher the proportion of short wavelength light such as a part of the excitation light contained in the emitted light. Therefore, the higher the color temperature of the emitted light, the lower the substantial luminous efficiency of the light-emitting element, and at the same time, it is easy to promote fading deterioration of pigments and dyes. According to this configuration, the cut-off wavelength is adjusted according to the color temperature of the emitted light, so that the substantial light emission efficiency of the light emitting element is increased to suppress power consumption, and the pigments and dyes are not easily faded. A lighting device that emits light can be provided.

Application Example 5 An electronic apparatus according to this application example includes the illumination device according to any one of Application Examples 1 to 4 and a color filter, and the light emitted from the illumination device is based on image information. And an electro-optical device that modulates the light.
According to this configuration, since the above-described illumination device is used as a light source of an electronic device, the substantial light emission efficiency of the light emitting element is increased to reduce the power consumption of the electronic device, and the color filter is also faded. It is possible to provide an electronic device that is not easily generated and has excellent durability.

Application Example 6 A projection display device according to this application example includes the illumination device according to any one of Application Examples 1 to 4 and a color filter, and outputs light emitted from the illumination device as image information. And an optical projection device that projects display light emitted from the electro-optical device.
According to this configuration, since the above-described illumination device is used as the light source of the projection display device, the substantial light emission efficiency of the light emitting element is increased and the power consumption of the projection display device is suppressed, and the color filter It is possible to provide a projection display device that is less likely to cause fading deterioration and has excellent durability.

Schematic explaining the outline | summary of the illuminating device concerning Embodiment 1. FIG. The figure which plotted the wavelength dispersion spectrum of hard white light, and the transmittance | permeability of an optical filter element. The figure which showed the relationship between the color temperature of hard white light, and a cutoff wavelength. Schematic explaining the outline | summary of the illuminating device concerning Embodiment 2. FIG. Schematic which shows the structure of the projection type display apparatus as an electronic device. 1 is a schematic diagram illustrating a configuration of a liquid crystal device as an electro-optical device. The figure explaining the transmittance | permeability of a color filter. FIG. 9 is a schematic cross-sectional view showing the structure of an electronic device according to Modification Example 1. FIG. 6 is a schematic cross-sectional view showing the structure of a lighting device according to Modification 2. FIG. 9 is a schematic cross-sectional view showing the structure of a lighting device according to Modification 3. FIG. 10 is a schematic cross-sectional view showing the structure of a lighting device according to modification example 4. FIG. 10 is a schematic cross-sectional view showing the structure of a projection display device according to modification example 5. FIG. 10 is a schematic cross-sectional view showing the structure of a projection display device according to modification example 6. The figure explaining the rod integrator used for the projection type display apparatus concerning the modification 6. FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following drawings, the scale of each layer and each member is made different from the actual scale so that each layer and each member can be recognized.

(Embodiment 1)
"Lighting device"
FIG. 1 is a schematic diagram for explaining the outline of the lighting apparatus according to the first embodiment. Hereinafter, the illumination device will be described with reference to FIG.

As shown in FIG. 1, the illuminating device 100 of this embodiment is provided with the light emitting element, the light conversion element, and the optical filter element at least. The light emitting element includes a solid light source that emits excitation light ExL and a phosphor 103 that is irradiated with the excitation light ExL. The light conversion element converts at least a part of light (radiated light) emitted radially from the light emitting element into substantially parallel light (parallel light). The optical filter element transmits the light having a wavelength longer than the cutoff wavelength λ _C (see FIG. 2) in the parallel light thus obtained, and reflects the light having a wavelength shorter than the cutoff wavelength λ _C. Let RfL.

  In the present embodiment, the solid light source is a light emitting diode (hereinafter referred to as LED; Light Emitting Diode) 101, and the LED 101 emits blue excitation light ExL. The central wavelength of the excitation light ExL is 445 nm. In addition, as the solid light source, an LED 101 that emits excitation light ExL having a different center wavelength may be used, or a solid laser may be used. For example, the third harmonic of an yttrium, aluminum, garnet laser (YAG laser) (wavelength 355 nm of the excitation light ExL) may be used as the solid light source.

  The phosphor 103 is in contact with the LED 101, covers the periphery thereof, receives the blue excitation light ExL from the LED 101, and emits yellow fluorescence. As a result, pseudo white light in which blue excitation light ExL and yellow fluorescence are mixed is emitted from the light emitting element. Since this pseudo white light includes high energy photons called blue excitation light ExL, it is hereinafter referred to as hard white light HWL. Examples of the phosphor 103 that emits yellow fluorescence upon receiving the excitation light ExL include, for example, cerium-activated yttrium aluminum garnet (YAG: Ce) phosphor 103 and barium silicon compound (BOS). A phosphor 103 or the like is used.

  The LED 101 is installed on the base material 102. The base material 102 has a function as a heat sink that releases heat generated when the LED 101 is turned on to the outside. Further, the LED 101 and the phosphor 103 may be in direct contact with each other, or another mediator may be interposed therebetween.

The hard white light HWL emitted radially from the light emitting element is guided to a condensing lens 104 which is a light converting element, and is converted into substantially parallel light (parallel light) by passing through the light converting element.
In short, the light emitting element is arranged in the vicinity of the focal position of the light conversion element such as the condensing lens 104, and the hard white light HWL emitted from the condensing lens 104 is substantially parallel to the light source axis. The light source axis refers to an axis passing through the center of the LED 101 and perpendicular to the light emitting surface of the solid light source. That is, the light source axis is an axis indicating the main light emission direction of the LED 101. If a regular reflection mirror is arranged on the light source axis, the light source axis is also bent according to the reflection of the mirror. The substantially parallel light (substantially parallel light beam) is a light beam that allows a dielectric multilayer film 105 described later to function as an optical filter element. Specifically, if the angle of the light beam with respect to the light source axis is θ, θ = 0 ° is an ideal light beam, and θ is in the range of 0 ° to less than 10 ° (0 ° ≦ θ <10 °). The group can be handled as a ray parallel to the light source axis without any problem. Since the solid angle of the cone of the half apex angle θ is 2π (1-cos θ), the light beam group in which the main component of the light beam emitted from the light conversion element is within the solid angle of 0.03π steradian is used as the light source axis without any problem. Parallel rays. Further, a light ray group in which θ is in the range of 0 ° or more and less than 15 ° (0 ° ≦ θ <15 °) (light rays in which the main component of the light beam emitted from the light conversion element is within a solid angle of 0.068π steradian. Group) can also be handled as light rays parallel to the light source axis. Up to a light ray group in which θ is in the range of 0 ° to less than 20 ° (0 ° ≦ θ <20 °) (a light ray group in which the main component of the light beam emitted from the light conversion element is in a solid angle of 0.121π steradian). Can be handled as light rays parallel to the light source axis.

An optical filter element is disposed on the exit side of the light conversion element. In other words, the light conversion element is disposed between the light emitting element and the optical filter element. In the present embodiment, the optical filter element is a dichroic filter and is the dielectric multilayer film 105, but photonic lattice can also be used as the optical filter element. The dielectric multilayer film 105 is disposed substantially perpendicular to the hard white light HWL became parallel rays, with transmitting light of wavelengths longer than the cutoff wavelength lambda _C, shorter wavelength than the cutoff wavelength lambda _C To reflect the light. In other words, the optical filter device, than the light of the cutoff wavelength lambda _C passes light of lower energy than the light of the cutoff wavelength lambda _C reflects the light of a high energy is returned to the original optical path. At least a part of the light reflected by the optical filter element (reflected light RfL) traces the optical path from the LED 101 to the dielectric multilayer film 105 in the reverse direction and irradiates the phosphor 103 again. The cutoff wavelength λ _C is set so that the optical filter element reflects at least a part of the excitation light ExL included in the hard white light HWL that has become a light beam parallel to the light source axis. In this way, the light that has passed through the optical filter element is light in which high-energy photons such as excitation light ExL are reduced from the hard white light HWL, and the light that has passed through the optical filter element is hereinafter referred to as soft white light SWL. Called.

  It is mainly short-wavelength light such as blue light and ultraviolet light that causes color fading and deterioration of pigments and dyes used in color filters, paintings, and printed materials. On the other hand, the emitted light from the light emitting element includes excitation light ExL having a short wavelength component and fluorescence having a long wavelength component emitted from the phosphor 103. Since the optical filter element partially removes short wavelength light such as a part of the excitation light ExL from the hard white light HWL, the ratio of the short wavelength light is reduced in the soft white light SWL irradiated by the illumination device, and the pigment and the dye are faded. An illumination device that emits light that is difficult to cause will be provided. Furthermore, the light reflected by the optical filter element (reflected light RfL) is short-wavelength light such as a part of the excitation light ExL, which irradiates the phosphor 103 again to release the fluorescence. In short, the phosphor 103 is irradiated with the excitation light ExL from the solid light source and the reflected light RfL from the optical filter element to emit fluorescence. Therefore, even if the excitation light ExL of the solid light source is weakened, a bright light source can be obtained. That is, the substantial light emission efficiency of the light emitting element can be increased and the power consumption can be suppressed.

  FIG. 2 is a diagram depicting the wavelength dispersion spectrum of hard white light and the transmittance of the optical filter element. FIG. 2A shows the case where the color temperature of the hard white light is 4700K, and FIG. 2B shows the color of the hard white light. This is the case when the temperature is 9000K. FIG. 3 is a diagram showing the relationship between the color temperature of hard white light and the cutoff wavelength. Next, the relationship between the hard white light HWL emitted from the light emitting element of the light source and the performance of the optical filter element will be described with reference to FIG. 2 and FIG.

  In FIG. 2, the chromatic dispersion spectrum of the hard white light HWL is standardized and drawn, and the transmittance TmR of the optical filter element is also drawn. The central wavelength of the excitation light ExL is 445 nm, and in the chromatic dispersion spectrum of the hard white light HWL, a sharp peak of the excitation light ExL appears in the vicinity of 445 nm. A broad peak appearing near 560 nm in the wavelength dispersion spectrum of the hard white light HWL is fluorescence from the phosphor 103. In FIG. 2A where the color temperature of the hard white light HWL is 4700K, the ratio of the fluorescence peak to the peak of the excitation light ExL is larger than in FIG. 2B where the color temperature of the hard white light HWL is 9000K. . That is, it can be seen that the higher the color temperature of the hard white light HWL, the higher the ratio of the excitation light ExL and the higher the ratio of high energy photons.

With respect to the cutoff wavelength λ _C , the optical filter element has a lower incident light transmittance TmR on the lower wavelength side and a higher incident light transmittance TmR on the higher wavelength side. Specifically, the cutoff wavelength λ _C of the optical filter element is a wavelength at which the transmittance TmR of the incident light through the optical filter element is 50%. As shown in FIG. 2, the cutoff wavelength λ _C can be changed according to the color temperature of the light emitted from the light source. That is, as shown in FIG. 2A, when the color temperature of the hard white light HWL is relatively low, the cut-off wavelength λ _C is set lower with reference to the center wavelength of the excitation light ExL. . On the other hand, as shown in FIG. 2B, when the color temperature of the hard white light HWL is relatively high, the cutoff wavelength λ _C is set higher with reference to the center wavelength of the excitation light ExL. The

Next, the relationship between the color temperature of the hard white light HWL and the cutoff wavelength λ _C will be described with reference to FIG. In FIG. 3, the color temperature of the emitted light (hard white light HWL) is represented by x (K), and the cutoff wavelength λ _C is represented by y (nm). The color temperature of light used to irradiate color filters and paintings used in electro-optical devices is ideally about 6000K to 6500K. If it is lower than 6000K, the lighting will be yellowish, and the colors originally shown by the electro-optical device or painting cannot be faithfully reproduced. It becomes reproducible. Moreover, if it is higher than 6500K, it will result in illumination containing high energy photons, which will cause color filters and paintings to fade, but if it is lower than 6500K, the proportion of high energy photons will decrease, and color filters and paintings will be prevented from fading. Things will be possible. FIG. 3 shows the relationship between the color temperature (x) of the hard white light HWL and the cutoff wavelength λ _C (y) such that the color temperature of the soft white light SWL is approximately 6000K to 6500K. That is, when the color temperature x of the hard white light HWL and the cutoff wavelength λ _C (y) satisfy the relationship y = 0.2048x + 397.18, the color temperature of the soft white light SWL is approximately 6000K to 6500K. . The optical filter element is set to have a cutoff wavelength λ _C determined from the relational expression shown in FIG. 3 according to the color temperature of the radiated light (hard white light HWL).

The higher the color temperature of the emitted light, the higher the proportion of short wavelength light such as a part of the excitation light ExL included in the emitted light. In other words, the higher the color temperature of the emitted light, the lower the luminous efficiency of the light emitting element, and at the same time, it is easy to promote the fading deterioration of the pigment or dye. According to the present embodiment, the cutoff wavelength λ _C is adjusted according to the color temperature of the emitted light, so that the substantial light emission efficiency of the light emitting element is increased and the power consumption is suppressed, and the pigment or dye is faded. It is possible to provide a lighting device that emits light that is difficult to deteriorate. The conventional illumination device has a problem that the light emission efficiency is low and the pigments and dyes are easily deteriorated by corrosion resistance. However, the illumination device 100 of this embodiment is an electro-optical device (a liquid crystal projector) described later. It is suitable for an illuminating device that illuminates a liquid crystal device) or an illuminating device that illuminates a work of art or a photograph.

(Embodiment 2)
"Other lighting devices"
FIG. 4 is a schematic diagram for explaining the outline of the lighting apparatus according to the second embodiment. Hereinafter, the illumination device will be described with reference to FIG.

  The illumination device 200 of this embodiment includes at least a light emitting element, a light conversion element, and an optical filter element. The light conversion element is different from that of the first embodiment. Other configurations are almost the same as those of the first embodiment. In the present embodiment, the first hemispherical reflector 204 that reflects the radiated light (hard white light HWL) from the light emitting element in the first direction, and the light reflected by the first reflector 204 in the first direction. The second reflection plate 206 that reflects in different second directions is a light conversion element.

  As shown in FIG. 4, the light emitting element includes an LED 201 as a solid light source and a phosphor 203 as in the light emitting element of the first embodiment. The phosphor 203 may be provided so as to seal the LED 201, and the cover member may be sealed so as to cover the phosphor 103. The LED 201 is provided on the base material 202. The base material 202 has a function as a heat sink for radiating heat generated when the LED 201 is turned on to the outside, or a function as a heat spreader for transferring heat to the external heat sink.

  The arcuate first reflecting plate 204 is attached to one end of the base material 202 so as to cover the light emitting element. Similarly, the other end of the arc forms an opening with the base material 202.

  The second reflecting plate 206 has a reflecting surface 206a having a parabolic cross section and a bent portion 206b where one end of the reflecting surface 206a is bent toward the reflecting surface 206a. A bent portion 206b is attached to the other end of the base material 202 so that the reflecting surface 206a faces the light emitting element side.

  Of the radiated light (hard white light HWL) from the light emitting element, the light that has passed through the opening formed by the base material 202 and the first reflecting plate 204 is directly incident on the reflecting surface 206a of the second reflecting plate 206. And reflected in the second direction. In addition, the light emitted in the normal direction from the light emitting element provided on the base material 202 is reflected by the reflection surface 204a of the first reflecting plate 204, and again by the bent portion 206b applied to the other end portion of the base material 202. The light is reflected, enters the reflection surface 206a of the second reflection plate 206, and is reflected in the second direction. Further, the light emitted to the first reflecting plate 204 side with an angle with respect to the normal direction is reflected by the reflecting surface 204a, enters the reflecting surface 206a of the second reflecting plate 206, and enters the second reflecting plate 206a. Reflected in the direction. As described above, the radiated light (hard white light HWL) from the light emitting element is reflected once to three times by the first reflecting plate 204 and the second reflecting plate 206, and is parallel to the second direction. Will be irradiated.

An optical filter element made of a dielectric multilayer film 205 is disposed on the light emission side of the optical conversion element. The dielectric multilayer film 205 is disposed substantially perpendicular to the hard white light HWL became parallel rays, than the light of the cutoff wavelength lambda _C passes light of lower energy than the light of the cutoff wavelength lambda _C Even reflect high energy light and return to the original optical path. At least a part of the light reflected by the optical filter element (reflected light RfL) traces the optical path from the LED 201 to the dielectric multilayer film 205 in reverse, and irradiates the phosphor 203 again to release the fluorescence. The other configuration is almost the same as that of the first embodiment.

According to the second embodiment, the following effects can be obtained.
The light conversion element converts the emitted light (hard white light HWL) from the light emitting element into parallel light over a wide solid angle. That is, the illumination device 200 can use the emitted light more efficiently.

(Embodiment 3)
"Electronics"
5A and 5B are schematic views showing a configuration of a projection display device as an electronic apparatus, wherein FIG. 5A is a schematic cross-sectional view seen from the side, and FIG. 6A and 6B are schematic views showing a configuration of a liquid crystal device as an electro-optical device, in which FIG. 6A is a plan view and FIG. FIG. 7 is a diagram for explaining the transmittance of the color filter. Next, the electronic apparatus of this embodiment will be described with reference to FIGS.

  As shown in FIGS. 5A and 5B, a projection display device 1000 as an electronic apparatus according to this embodiment includes a lighting device 100, a liquid crystal device 500 as an electro-optical device, and a projection as a projection optical system. And a lens 601. The liquid crystal device 500 includes a color filter 522 (see FIG. 6), which modulates illumination light emitted from the illumination device 100 based on image information and converts the illumination light into display light. The converted display light is emitted from the liquid crystal device 500 and projected onto a screen or the like by the projection lens 601. The color filter 522 used in the electro-optical device is an absorption light type using a pigment or a dye.

  The electronic device includes the light emitting element (LED 101, base material 102, phosphor 103, etc.), the light conversion element (condenser lens 104, etc.), and the optical filter element (dielectric multilayer film 105, etc.) described in the first embodiment. In addition to each configuration, a polarization beam splitter 400 as a polarization conversion element, and a light shielding box 150 that houses the condenser lens 104 and the polarization beam splitter 400 so that light from the outside does not enter the liquid crystal device 500 are included. It is configured.

The optical centers of the LED 101, the condenser lens 104, the polarization beam splitter 400, and the liquid crystal device 500 are arranged on the same light source axis. Although the projection lens 600 is arranged on the same light source axis, when tilting projection is performed, the axis is intentionally shifted.
The phosphor 103 is disposed between the LED 101 and the condenser lens 104. Since it is necessary for light beams parallel to the light source axis to be incident substantially perpendicularly on the dielectric multilayer film 105, the optical filter element is disposed on the emission side of the light conversion element (condition 1). At the same time, since the optical filter element converts the hard white light HWL into the soft white light SWL, the optical filter element needs to be arranged on the incident side of the electro-optical device (liquid crystal device 500) having a color filter (condition 2). . In the present embodiment, the optical filter element is disposed immediately after the exit surface of the light conversion element. However, if it is between the light conversion element and the electro-optical device, that is, the above Condition 1 and Condition 2 can be satisfied. For example, it may be placed anywhere. For example, the optical filter element is placed immediately before the entrance surface of the polarizing beam splitter 400, immediately after the exit surface of the polarization beam splitter 400, just before the entrance surface of the dust-proof glass 160, just after the exit surface of the dust-proof glass 160, and incident on the electro-optical device. You may arrange | position just before a surface. Alternatively, the optical filter element may be directly formed on the incident surface of the polarizing beam splitter 400 itself. Furthermore, when the dielectric multilayer film 105 is built in the electro-optical device, the dielectric multilayer film 105 may be disposed immediately before the incident surface of the color filter. Or you may provide an optical filter element in multiple places among these. However, from the viewpoint of efficiently returning the reflected light RfL from the optical filter element to the phosphor 103 to save power, it is arranged immediately after the exit surface of the light conversion element as in this embodiment. preferable.

  The polarization beam splitter 400 as a polarization conversion element is a device that converts the light from the illumination device 100 into polarized light (in this case, S wave), thereby improving the light utilization efficiency.

  Next, the liquid crystal device 500 will be described with reference to FIG. As shown in FIGS. 6A and 6B, the liquid crystal device 500 according to the present embodiment includes an element substrate 510 and a counter substrate 520 that are disposed to face each other, and a liquid crystal layer 550 that is sandwiched between the pair of substrates. . As the base material 510s of the element substrate 510 and the base material 520s of the counter substrate 520, a transparent substrate such as a quartz substrate or a glass substrate is used.

  The element substrate 510 is slightly larger than the counter substrate 520, and both the substrates are bonded together via a sealant 540 disposed along the outer periphery of the counter substrate 520, and has positive or negative dielectric anisotropy in the gap. Liquid crystal is sealed to form a liquid crystal layer 550. As the sealing material 540, for example, an adhesive such as a thermosetting or ultraviolet curable epoxy resin is employed. The sealant 540 is mixed with a spacer (not shown) for keeping the distance between the pair of substrates constant.

  A parting part 521 is provided inside the sealing material 540. The parting part 521 is made of, for example, a light-shielding metal or metal oxide, and the inside of the parting part 521 is a pixel region E. In the pixel region E, a plurality of sub-pixels P are arranged in a matrix. The sub-pixels P are provided corresponding to red (R), green (G), blue (B), and white (W), and one sub-pixel P is provided by four sub-pixels P corresponding to R, G, B, and W. One pixel is constructed. In the present embodiment, square sub-pixels P are arranged in 2 rows and 2 columns to form a square pixel.

  The pixel region E may include a plurality of dummy pixels arranged so as to surround a plurality of effective sub-pixels P that contribute to display. Although not shown in FIG. 6, also in the pixel region E, a light shielding portion that divides a plurality of subpixels P in a plane is provided on each of the element substrate 510 and the counter substrate 520.

  A data line driving circuit 501 is provided between the sealing material 540 along the first side of the element substrate 510 and the first side. Further, an inspection circuit 503 is provided inside the sealing material 540 along the second side facing the first side. Further, a scanning line driving circuit 502 is provided inside the sealing material 540 along the third and fourth sides that are orthogonal to the first side and face each other. A plurality of wirings 505 that connect the two scanning line driving circuits 502 are provided inside the sealing material 540 on the second side. Wirings connected to the data line driving circuit 501 and the scanning line driving circuit 502 are connected to a plurality of external connection terminals 504 arranged along the first side. Hereinafter, the direction along the first side will be referred to as the X direction, and the directions along the third and fourth sides perpendicular to the first side and facing each other will be described as the Y direction.

  As shown in FIG. 6B, on the surface of the substrate 510s on the liquid crystal layer 550 side, a light-transmissive pixel electrode 515 provided for each sub-pixel P and a thin film transistor (TFT; Thin) as a switching element. A film transistor (hereinafter referred to as TFT) 530, a signal wiring (not shown), and an alignment film 518 covering the plurality of pixel electrodes 515 are formed. In addition, a light shielding structure is employed that prevents light from entering a semiconductor layer in the TFT 530 and causing a light leakage current to flow to cause an inappropriate switching operation. That is, the element substrate 510 in this embodiment includes at least the base material 510 s, the pixel electrode 515, the TFT 530, the signal wiring, and the alignment film 518.

  On the surface of the base material 520 s on the liquid crystal layer 550 side, a parting part 521, a color filter 522 having a pigment corresponding to each color of R, G, and B, and a planarization layer formed so as to cover the color filter 522 523, a common electrode 524 provided so as to cover the planarization layer 523 over at least the pixel region E, and an alignment film 525 covering the common electrode 524 are provided. That is, the counter substrate 520 in this embodiment includes at least the base material 520 s, the light blocking parting part 521, the color filter 522, the planarization layer 523, the common electrode 524, and the alignment film 525.

  As shown in FIG. 6A, the parting part 521 is provided in a position overlapping the scanning line driving circuit 502 and the inspection circuit 503 in a plane. Thus, the light incident from the counter substrate 520 side is shielded, and the malfunction of the peripheral circuits including these driving circuits due to the light is prevented. Further, unnecessary stray light is shielded from entering the pixel region E, and high contrast in the display of the pixel region E is ensured.

  The planarization layer 523 is made of an inorganic material such as silicon oxide, for example, and is provided so as to cover the parting part 521 and the color filter 522 with light transmittance. In other words, the planarization layer 523 relaxes unevenness generated on the base material 520 s by the parting portion 521 and the color filter 522. As a method for forming such a planarization layer 523, for example, a method of forming a film using a plasma CVD method or the like can be given.

  The common electrode 524 is made of a transparent conductive film such as ITO, for example, covers the planarization layer 523, and, as shown in FIG. 6A, the vertical conductive portions 506 provided at the four corners of the counter substrate 520 side the element substrate 510 side. It is electrically connected to the wiring.

  The alignment film 518 covering the pixel electrode 515 and the alignment film 525 covering the common electrode 524 are selected based on the optical design of the liquid crystal device 500. For example, an organic material such as polyimide is formed, and the surface thereof is rubbed so that liquid crystal molecules having positive dielectric anisotropy are subjected to a substantially horizontal alignment treatment, or SiOx (silicon oxide) Inorganic materials such as those described above are formed by vapor deposition, and liquid crystal molecules having negative dielectric anisotropy are subjected to a substantially vertical alignment treatment.

  Such a liquid crystal device 500 is a transmissive type, and in the present embodiment, a normally black mode optical design is employed in which the sub-pixel P is darkly displayed when not driven. Depending on the optical design, a polarizing beam splitter 400 (see FIG. 5) is disposed on the light incident side, and a polarizing element 561 (see FIG. 5) is disposed on each of the light incident side and the light exit side. If the liquid crystal device 500 is driven based on the image signal, the illumination light can be modulated and the display light corresponding to the full color can be emitted. The polarizing element 561 may be a so-called polarizing plate or a combination of a polarizing plate and a retardation plate. In the figure, the polarizing element 561 is provided separately from the liquid crystal device 500, but may be directly attached to the liquid crystal device 500 depending on the case.

  Next, the effect of this embodiment will be described with reference to FIG. FIG. 7 is a diagram showing the presence or absence of color fading deterioration of the color filter. The horizontal axis of FIG. 7 shows the wavelength of light, and the vertical axis shows the transmittance of the red color filter. The graph described as Embodiment 1 in FIG. 7 shows the transmittance of the red color filter in the initial stage and the transmittance of the red color filter when the illumination device described in Embodiment 1 is irradiated for 1000 hours. The two are almost identical. That is, the red color filter hardly undergoes fading deterioration even when the light (soft white light SWL) of the lighting device described in Embodiment 1 is irradiated for 1000 hours. On the other hand, the graph described as the comparative example in FIG. 7 is irradiated with the red color filter with the hard white light HWL for 1000 hours in the illumination device in which the light filter element is removed from the illumination device described in the first embodiment. In some cases, it can be seen that the transmittance of light having a wavelength of 450 nm or less is increased, and the red color filter is deteriorated. Thus, in this embodiment, since the illuminating device described in Embodiment 1 is used as the light source of the projection display device, the substantial light emission efficiency of the light emitting element is increased and the power consumption of the projection display device is reduced. It is possible to provide a projection type display device that is suppressed and that is less likely to cause color fading deterioration of the color filter and has excellent durability.

  The present invention is not limited to the above-described embodiment, and various changes and improvements can be added to the above-described embodiment. A modification will be described below.

(Modification 1)
"Form of direct-view display device"
FIG. 8 is a schematic cross-sectional view illustrating the structure of an electronic device according to the first modification. Next, an electronic apparatus according to this modification will be described with reference to FIG. In addition, about the component same as Embodiment 1 thru | or 3, the same code | symbol is attached | subjected and the overlapping description is abbreviate | omitted.

  This modification is different from the third embodiment in that the electronic device is a direct-view display device. The other configuration is almost the same as that of the third embodiment. In the third embodiment, the electronic apparatus is the projection display device 1000. On the other hand, in this modification, the electronic device is a direct view display device 2000. That is, the light guide plate 700 is disposed on the back surface (the surface opposite to the display surface) of the liquid crystal device 500, and the lighting device 100 is disposed on the end portion of the light guide plate. The soft white light SWL emitted from the illumination device 100 is incident on the liquid crystal device 500 through the light guide plate 700. The liquid crystal device includes red, green, and blue pigment color filters and can perform color display.

  In addition, as an electronic apparatus (projection type display apparatus 1000 or direct view type display apparatus 2000) provided with the illuminating device 100, for example, a projection type HUD (head up display), a direct view type HMD (head mounted display), or an electronic book is used. And personal computer, digital still camera, liquid crystal television, viewfinder type or monitor direct view type video recorder, car navigation system, POS and other information terminal devices.

(Modification 2)
“Form 1 with different light emitting elements”
FIG. 9 is a schematic cross-sectional view showing the structure of a lighting device according to Modification 2. Next, the illuminating device 100 concerning this modification is demonstrated using FIG. In addition, about the component same as Embodiment 1 thru | or 3, the same code | symbol is attached | subjected and the overlapping description is abbreviate | omitted. In FIG. 9, for the convenience of explanation, in the hard white light HWL, the soft white light SWL, and the like, only light parallel to the light source axis is drawn.

  The present modification (FIG. 9) differs from the first embodiment (FIG. 1) in the form of the light emitting element. Other configurations are almost the same as those of the first embodiment. In the first embodiment, the phosphor 103 covers the LED 101. On the other hand, in this modification, the LED 101 and the phosphor 103 are arranged slightly apart. In this way, if the configuration can efficiently receive the excitation light ExL from the LED 101 and emit fluorescence, it is not necessary to cover the LED 101 with the phosphor 103 as shown in FIG. Therefore, the influence of the heat generated by the LED 101 received by the phosphor 103 can be reduced. The lighting device 100 described in the present modification can be applied to the projection display device and the electronic device described in the first to third embodiments and the first modification.

(Modification 3)
"Form 2 with different light emitting elements"
FIG. 10 is a schematic cross-sectional view showing the structure of a lighting device according to Modification 3. Next, the illuminating device 100 concerning this modification is demonstrated using FIG. In addition, about the component same as Embodiment 1 thru | or 3, the same code | symbol is attached | subjected and the overlapping description is abbreviate | omitted. In FIG. 10, only the parallel light is drawn in the hard white light HWL, the soft white light SWL, and the like for convenience of explanation.

The present modification (FIG. 10) differs from the first embodiment (FIG. 1) and the second modification (FIG. 9) in the form of the light emitting element. Other configurations are almost the same as those in the first embodiment and the second modification. In the first embodiment, the LED 101 and the phosphor 103 are in contact with each other. In the second modification, the LED 101 and the phosphor 103 are slightly separated from each other. On the other hand, in this modification, the LED 101 and the phosphor 103 are separated from each other, and the light source lens 106 is disposed therebetween. In this way, various optical elements may be disposed between the LED 101 and the phosphor 103 in order to efficiently receive the excitation light ExL from the LED 101 and improve the light emission efficiency of the phosphor 103. Thus, the excitation light ExL is collected and irradiated onto the phosphor 103, whereby the area of the phosphor that emits light can be reduced, and a suitable characteristic can be obtained with the projection display device.
In this modification, a convex light source lens 106 is used for this optical element, but it goes without saying that a concave lens, a reflecting mirror, or the like may be combined. The lighting device 100 described in the present modification can be applied to the projection display device and the electronic device described in the first to third embodiments and the first modification.

(Modification 4)
"Form 3 with different light emitting elements"
FIG. 11 is a schematic cross-sectional view showing the structure of a lighting device according to Modification 4. Next, the illuminating device 100 concerning this modification is demonstrated using FIG. In addition, about the component same as Embodiment 1 thru | or 3, the same code | symbol is attached | subjected and the overlapping description is abbreviate | omitted. In FIG. 11, for the convenience of explanation, only the parallel light is drawn in the hard white light HWL, the soft white light SWL, and the like.

  This modification (FIG. 11) differs from Embodiment 1 (FIG. 1) in the form of the light emitting element. Other configurations are almost the same as those of the first embodiment. In the first embodiment, the phosphor 103 covers the LED 101. On the other hand, in the present modification, the phosphor 103 is disposed on the light emitting surface of the LED 101. In this way, if the configuration can efficiently receive the excitation light ExL from the LED 101 and emit fluorescence, there is no need to cover the LED 101 with the phosphor 103 as shown in FIG. The phosphors 103 may be stacked and arranged on one surface. The lighting device 100 described in the present modification can be applied to the projection display device and the electronic device described in the first to third embodiments and the first modification.

(Modification 5)
“Form 1 with different configuration of projection display device”
FIG. 12 is a schematic cross-sectional view showing the structure of a projection display device according to Modification 5. Next, a projection display apparatus 1000 according to this modification will be described with reference to FIG. In addition, about the component same as Embodiment 1 thru | or 3, the same code | symbol is attached | subjected and the overlapping description is abbreviate | omitted.
In FIG. 12, only the parallel light is drawn in the hard white light HWL, the soft white light SWL, and the like for convenience of explanation.

  This modification differs from the third embodiment (FIG. 5) in the optical system used in the projection display apparatus 1000. The other configuration is almost the same as that of the third embodiment. In the third embodiment (FIG. 5), no special optical system is used between the illumination device 100 and the liquid crystal device 500 other than the polarizing beam splitter 400. On the other hand, in this modified example, a fly eye integrator 800 is disposed between the illumination device 100 and the liquid crystal device 500 in addition to the polarization beam splitter 400. Thereby, the illuminance distribution of the light incident on the liquid crystal device 500 becomes uniform, and the illuminance distribution can be made bright and uniform in every corner of the pixel region E of the liquid crystal device 500.

  The fly eye integrator 800 includes at least a first multi-lens 810, a second multi-lens 820, and a superimposing lens 830. The first multi-lens 810 and the second multi-lens 820 are also called fly-eye lenses, and are a plurality of small lenses arranged vertically and horizontally on the light incident surface. In this modification, the fly eye integrator 800 further includes an adjustment lens 840, and condenses the light flux with uniform illuminance on the liquid crystal device 500.

  The soft white light SWL emitted from the illumination device 100 side passes through the first multilens 810, the second multilens 820, the polarization beam splitter 400, the superimposing lens 830, and the adjustment lens 840, and is guided to the liquid crystal device 500. Other configurations are the same as those in the third embodiment (FIG. 5). Of course, the illumination device 100 described in the second to fourth modifications can be applied to the illumination device 100 described in the present modification.

(Modification 6)
“Form 2 with different configuration of projection display device”
FIG. 13 is a schematic cross-sectional view showing the structure of a projection display device according to Modification 6. FIG. 14 is a diagram for explaining a rod integrator used in the projection display device according to the sixth modification. Next, a projection display apparatus 1000 according to this modification will be described with reference to FIGS. 13 and 14. In addition, about the component same as Embodiment 1 thru | or 3, the same code | symbol is attached | subjected and the overlapping description is abbreviate | omitted. In FIG. 13, only the light parallel to the light source axis is drawn in the hard white light HWL and the soft white light SWL for the convenience of explanation.

  This modification differs from the third embodiment (FIG. 5) in the optical system used in the projection display apparatus 1000. The other configuration is almost the same as that of the third embodiment. In the third embodiment (FIG. 5), no special optical system is used between the illumination device 100 and the liquid crystal device 500 other than the polarizing beam splitter 400. On the other hand, in this modified example, a rod integrator 900 is disposed between the illumination device 100 and the liquid crystal device 500 in addition to the polarizing beam splitter 400. Thereby, the illuminance distribution of the light incident on the liquid crystal device 500 becomes uniform, and the illuminance distribution can be made bright and uniform in every corner of the pixel region E of the liquid crystal device 500.

  The rod integrator 900 includes at least a rod 910 that is hollow and has a reflective surface formed inside by a metal coat or the like. Inside the rod 910, the soft white light SWL repeats multiple total reflections, increasing the illuminance uniformity in a plane perpendicular to the light source axis. The shape of the rod integrator 900 may be a taper shape or may be a reverse taper shape. In FIG. 13, the rod 910 is hollow, but instead, as shown in FIG. 14, a glass rod 920 filled with glass may be used as the rod integrator 900. Also in this case, the soft white light SWL is totally reflected at the glass interface. The light flux with the illuminance from the rod integrator 900 aligned in the plane is condensed on the liquid crystal device 500.

  The soft white light SWL emitted from the illumination device 100 side passes through the polarization beam splitter 400 and the rod integrator 900 and is guided to the liquid crystal device 500. Other configurations are the same as those in the third embodiment (FIG. 5). Of course, the illumination device 100 described in the second to fourth modifications can be applied to the illumination device 100 described in the present modification.

  (Modification 7) The liquid crystal device 500 in the projection display device 1000 is not limited to the transmissive type. A reflective liquid crystal device in which the pixel electrode has light reflectivity can also be employed.

  (Modification 8) The electro-optical device in the projection display apparatus 1000 is not limited to the liquid crystal system. For example, the illumination device 100 of the present invention can be applied even to a mirror device that modulates incident light by changing the angle of a mirror provided for each pixel based on image information.

  (Variation 9) The sub-pixel P in the liquid crystal device 500 has red (R), green (G), blue (B) instead of red (R), green (G), blue (B), and white (W). ) Stripe arrangement, or yellow (Y) sub-pixels may be added. The arrangement is not limited to squares or stripes, but may be arranged in tiles.

  DESCRIPTION OF SYMBOLS 100 ... Illuminating device, 101 ... LED, 102 ... Base material, 103 ... Phosphor, 104 ... Condensing lens, 105 ... Dielectric multilayer, 106 ... Light source lens, 150 ... Light shielding box, 160 ... Dust-proof glass, 200 ... Illumination Device 201 ... LED 202 ... base material 203 ... phosphor 204 ... first reflection plate 204a ... reflection surface 205 ... dielectric multilayer film 206 ... second reflection plate 206a ... reflection surface 206b ... bending Part 400, polarization beam splitter, 500 liquid crystal device, 510 ... element substrate, 515 ... pixel electrode, 518 ... alignment film, 520 ... counter substrate, 522 ... color filter, 523 ... flattening layer, 524 ... common electrode, 525 Alignment film, 530 TFT, 550 Liquid crystal layer, 561 Polarizing element, 601 Projection lens, 700 Light guide plate, 800 Fly eye integrator 810 ... first multi-lens, 820 ... second multi-lens, 830 ... superimposing lens, 840 ... adjusting lens, 900 ... rod integrator, 910 ... rod, 1000 ... projection display device, 2000 ... direct view display device.

Claims (6)

A light emitting element having a solid light source that emits excitation light and a phosphor irradiated with the excitation light;
A light conversion element that converts at least a part of light (radiated light) emitted from the light emitting element into substantially parallel light (parallel light);
An illuminating device comprising: an optical filter element that transmits light having a wavelength longer than a cutoff wavelength in the parallel light and reflects light having a wavelength shorter than the cutoff wavelength.   The lighting device according to claim 1, wherein the optical filter element reflects at least a part of the excitation light included in the parallel light.   The lighting device according to claim 1, wherein at least a part of the light reflected by the optical filter element irradiates the phosphor. When the color temperature of the emitted light is represented by x (K) and the cut-off wavelength is represented by y (nm), the color temperature x and the cut-off wavelength y are:
y = 0.0048x + 397.18
The illumination device according to any one of claims 1 to 3, wherein the relationship is satisfied. The lighting device according to any one of claims 1 to 4,
An electronic apparatus comprising: an electro-optical device having a color filter and modulating light emitted from the illumination device based on image information. The lighting device according to any one of claims 1 to 4,
An electro-optic device having a color filter and modulating light emitted from the illumination device based on image information;
A projection optical system for projecting display light emitted from the electro-optical device.

Images