JP2003161906A - Display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a display device which can make high-luminance display. <P>SOLUTION: A 1st display unit 11 emits 1st display light L1. A 2nd display unit 12 emits 2nd display light L2. A transmission and reflection member 13 reflects the 1st display light L1 and transmits the 2nd display light L2. The transmission and reflection member 13 has such transmission and reflection characteristics that the reflectance is higher than the transmittance within a 1st wavelength region including the wavelength of the 1st display light L1 and the transmittance is higher than the reflectance within a 2nd wavelength region including the wavelength of the 2nd display light L2. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display device having a plurality of display devices.

[0002]

2. Description of the Related Art Conventionally, a head-up display for displaying a virtual image V by reflecting display light L projected by a display device 2 arranged on a dashboard 1 of a vehicle toward a driver 4 by a windshield 3. Yes (see FIG. 9). The display device 2 includes a first emissive display 5 and a second emissive display 6.
And a half mirror 7 and a concave mirror 8. The first light emitting display 5, the second light emitting display 6, the half mirror 7 and the concave mirror 8 are housed in a housing 9. (See Figure 10).

Display light L1 emitted from the first light-emitting display 5
Is reflected by the half mirror 7, further reflected by the concave mirror 8, and projected onto the windshield 3. On the other hand, the display light L2 emitted from the second light emitting display 6 is transmitted through the half mirror 7, reflected by the concave mirror 8 and projected onto the windshield 3. Such a head-up display is provided by selectively displaying / non-displaying the first emissive display 5 and the second emissive display 6, or by the first emissive display 5 and the second emissive display 5. By displaying the light-emitting display 6 simultaneously, the virtual image V can be displayed in various modes.

[0004]

However, the reflectance and the transmittance of the half mirror 7 are about 50%, respectively, and about 50% of the display light L1 is transmitted through the half mirror 7, and the reflectance of the display light L2 is about 50%. Since 50% is reflected by the half mirror 7, there is a problem that the brightness of the virtual image V is low. That is, about 50% of the display light L1 becomes the transmitted light L3, about 50% of the display light L2 becomes the reflected light L4, and the virtual image V
Can not contribute to the display of. The present invention has been made in view of this problem, and provides a display device capable of high-luminance display by using a transflective member having reflectance and transmittance corresponding to the wavelength of display light. is there.

[0005]

In order to solve the above-mentioned problems, the present invention provides a first display 1 which emits a first display light L1.
1 and a second indicator 12 that emits a second display light L2,
The second display light L2 is reflected by reflecting the first display light L1.
Display device 1 having a transflective member 13 for transmitting light
0, the transmissive / reflecting member 13 has a reflectance higher than the transmittance in the first wavelength range including the wavelength of the first display light L1 and includes the wavelength of the second display light L2. It has a transmission / reflection characteristic in which the transmittance is higher than the reflectance in the second wavelength range.

According to the present invention, at least one of the first display 11 and the second display 12 has a liquid crystal display element 16, 33 and a light emitting element 35 for illuminating the liquid crystal display element 16, 33. It is a liquid crystal display having 18.

The present invention also provides the light emitting devices 16 and 33.
Is a light emitting diode.

The present invention also relates to the liquid crystal display device 16,
A dot matrix type 33 is driven by the multiple line simultaneous selection driving method.

The present invention also relates to the liquid crystal display device 16,
Reference numeral 33 is for displaying a moving image.

Further, according to the present invention, the first indicator 11 is provided.
Is a liquid crystal display having a liquid crystal display element 16.

Further, according to the present invention, the transmitting / reflecting member transmits infrared rays.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment in which the present invention is applied to a vehicle head-up display will be described below. Figure 1
6 to 6 show the first embodiment.

The display device 10 comprises a first liquid crystal display 11
(First display), second liquid crystal display 12 (second display), dichroic mirror 13 (transmissive reflection member)
And a reflector 14. First liquid crystal display 11
Is disposed on the front side of the dichroic mirror 13, and the second liquid crystal display 12 includes the dichroic mirror 1
3 is arranged on the rear surface side. Liquid crystal display 11, 12,
The dichroic mirror 13 and the reflector 14 are housed in a housing 15.

The first liquid crystal display 11 displays the speed of the vehicle, the number of revolutions of the engine, etc., and includes a liquid crystal display element 16, a reflecting member 17, a light emitting diode 18 (light emitting element), and a hard wiring board 19. It has (see FIG. 2). Figure 3
As shown in FIG.
1, it has a liquid crystal cell 22 for optical compensation and polarizing plates 23, 24. The display liquid crystal cell 21 is a transparent electrode film 2 made of indium tin oxide (ITO).
Liquid crystal 29 is enclosed in a pair of translucent substrates 27, 28 provided with 5, 26. Each transparent electrode film 25, 26
Are in the form of stripes orthogonal to each other, and the portions where the transparent electrode film 25 and the transparent electrode film 26 face each other are pixels. The optical compensation liquid crystal cell 22 is a pair of translucent substrates 30 and 31 in which a liquid crystal 32 is sealed, and is disposed behind the display liquid crystal cell 21. The polarizing plate 23 is attached to the front surface of the display liquid crystal cell 21, and the polarizing plate 24
Is attached to the rear surface of the optical compensation liquid crystal cell 22.

The plurality of light emitting diodes 18 are arranged close to each other and connected to the hard wiring board 19. The light emitting diode 18 is about 500 nm to about 550 n.
It emits light of wavelength m and emits green light. The reflecting member 17 is made of white resin and has a rectangular tube shape. The reflection member 17 reflects the light emitted from the light emitting diode 37 on the reflection surface 17a on the inner circumference to the liquid crystal display element 16. The liquid crystal display element 16 is illuminated by the light emitting diode 18 that emits green light, and the display light L1 becomes green.

The second liquid crystal display 12 is a liquid crystal display element 3
3, light diffusion plate 34, light emitting diode 35 (light emitting element),
It has a hard wiring board 36 (see FIG. 4). The liquid crystal display element 33 includes a display liquid crystal cell 37 and an optical compensation liquid crystal cell 3.
8 and polarizing plates 39 and 40. Liquid crystal display element 3
The configuration of No. 3 is the same as that of the liquid crystal display element 16, and thus detailed description will be omitted.

The light emitting diode 36 emits light having a wavelength of about 650 nm to about 750 nm and emits red light. The light emitting diode 1 of the first liquid crystal display 11
8 is a discrete type, whereas the light emitting diode 35 of the second liquid crystal display 12 is a chip type. The light diffusing plate 34 is disposed between the liquid crystal display element 33 and the light emitting diode 35, and the light emitted by the light emitting diode 35 is diffused by the light diffusing plate 34 so that the liquid crystal display element 33 transmits with substantially uniform brightness. Illuminated. The liquid crystal display element 33, the light diffusion plate 34, and the hard wiring board 36 are assembled to the frame 41.

The second liquid crystal display 12 is for displaying an image of an infrared camera (not shown) for picking up an image of the front of the vehicle. That is, the second liquid crystal display 12 is a display of a so-called night vision device. Liquid crystal display element 33
Is driven by the MLA method (simultaneous multiple line selection driving method), and an image in front of the vehicle captured by the infrared camera is displayed.

The dichroic mirror 13 comprises a glass substrate 45 and a reflecting film 46 formed on the front surface of the glass substrate 45 by vapor deposition (see FIG. 5). The dichroic mirror 13 reflects the display light L1 of the first display 11 and transmits the display light L2 of the second display 12. The dichroic mirror 13 is arranged so as to be inclined at approximately 45 ° with respect to the direction of the display light L1 and the direction of the display light L2.

As shown in FIG. 6, the dichroic mirror 13 has a transmissive reflection characteristic in which a reflectance is higher than the transmittance in a wavelength region smaller than 600 nm and a transmittance is higher than the reflectance in a wavelength region larger than 600 nm. Have That is, the wavelength range of visible light (about 400 nm to about 750 n
In m), the transmission / reflection characteristics of the dichroic mirror 13 are such that the reflectance is higher than the transmittance in the wavelength range of 400 nm to 600 nm (first wavelength range).
In the wavelength range of 0 nm to 750 nm (second wavelength range),
The transmittance is higher than the reflectance.

The reflector 14 comprises a concave mirror 48, a mirror holder 49, a gear 50 and a stepping motor 51. The concave mirror 48 reflects the display light L and projects it on the windshield of the vehicle. The concave mirror 48 is adhered to the mirror holder 49 with a double-sided adhesive tape. The concave mirror 48 is formed by depositing aluminum (Al) on a resin such as polycarbonate (PC) to form a reflective film. The mirror holder 49 is made of resin such as PBT, and the gear portion 49a and the shaft portion 49b are integrally formed. The shaft portion 49b is axially supported by a bearing portion (not shown) provided in the housing 15.

The stepping motor 51 rotates the concave mirror 48 to adjust the projection direction of the display light L. The gear 50 is attached to the rotating shaft of the stepping motor 51,
It meshes with the gear part 49a. The driver operates a switch (not shown) to adjust the angle of the concave mirror 48 so that the display light L is reflected at the eye position.

The display device 10 selectively displays / hides the first liquid crystal display 11 and the second liquid crystal display 12, or displays the first liquid crystal display 11 and the second liquid crystal display 12. By displaying at the same time, the virtual image can be displayed in various modes.

7 and 8 show the second embodiment. The second embodiment is different only in the indicator display 53 (second display), and other configurations are the same as those in the first embodiment.

The indicator display 53 has an indicator display plate 54, a light emitting diode 55, a hard wiring board 56, and a case body 57.
It notifies the rise of exhaust temperature and the drop of engine oil pressure. The indicator display plate 54 is formed by printing four indicator display portions 59 made of a light-transmitting colored layer and a light-shielding portion 60 made of a light-shielding colored layer on a substrate 58 made of a light-transmitting resin such as polycarbonate. Is.

Two light emitting diodes 55 are provided for each of the indicator display portions 59, and two hard wiring boards 56 are provided.
It is installed in. The light emitting diode 55 emits red light and is the same as the light emitting diode 35 of the second liquid crystal display 12, and thus detailed description thereof will be omitted. The case body 57 has a light shielding wall 57a, and the indicator display plate 54 and the hard wiring board 56 are assembled to the case body 57. The dichroic mirror 13 has a high transmittance even at a wavelength of 700 nm or more, and transmits not only red light but also infrared IR.

According to the first and second embodiments, since the dichroic mirror 13 easily reflects the first display light L1 and easily transmits the second display light L2, the display brightness is high. In other words, the transmission / reflection characteristic of the dichroic mirror 13 is the wavelength of the first display light L1 (about 500 nm to about 55 nm).
0 nm) including the first wavelength range (400 nm to 600 n)
m), the reflectance is higher than the transmittance, and the reflectance is higher than the reflectance in the wavelength range of the second wavelength range (600 nm to 750 nm) including the wavelength of the second display light L2 (about 650 nm to about 750 nm). Also has a high transmittance, and most of the first display light L1 and the second display light L2 contribute to the display of the virtual image, so that the display brightness is high.

Further, according to the second embodiment, since the dichroic mirror 13 transmits infrared rays, even if the infrared rays IR contained in the sunlight irradiate the dichroic mirror 13 via the reflector 14, the liquid crystal display There is no possibility that the polarizing plates 23 and 24 of the liquid crystal display element 16 will be damaged by sunlight because they are not reflected by the container 11. The infrared ray IR transmitted through the dichroic mirror 13 is applied to the indicator display 53, but the indicator display 53
Does not use a liquid crystal display element, the liquid crystal display 11
There is no problem because it has heat resistance compared to.

The display of this embodiment is the liquid crystal displays 11 and 12 or the indicator display 53.
For example, it may be a fluorescent display tube or an electroluminescent display element. The light emitting element may be a bulb or the like, but the light emitting diodes 35 and 18 are desirable because they have a narrow emission wavelength range.
Further, although the present embodiment is a head-up display in which the display light L is reflected by the windshield to be visually recognized, it goes without saying that the present invention can also be applied to a display device that directly looks at the display light L.

[0030]

Industrial Applicability The present invention provides a first display device which emits a first display light, a second display device which emits a second display light, and a second display device which reflects the first display light. A display device having a transflective member that transmits display light, wherein the transflective member has a higher reflectance than a transmittance in a first wavelength range including the wavelength of the first display light, and It has a transflective property in which the transmissivity is higher than the reflectivity in the second wavelength range including the wavelength of the second display light, and high-luminance display can be performed.

Further, according to the present invention, the transflective member transmits infrared rays, and there is no possibility that the infrared rays will enter the first display.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing a first embodiment of the present invention.

FIG. 2 is a sectional view of a first liquid crystal display showing the embodiment.

FIG. 3 is an enlarged cross-sectional view of a liquid crystal display element showing the embodiment.

FIG. 4 is a sectional view of a second liquid crystal display showing the embodiment.

FIG. 5 is a sectional view of a dichroic mirror showing the embodiment.

FIG. 6 is a transmission / reflection characteristic diagram of the dichroic mirror according to the embodiment.

FIG. 7 is a schematic configuration diagram showing a second embodiment of the present invention.

FIG. 8 is a cross-sectional view of an indicator display showing the embodiment.

FIG. 9 is an explanatory diagram of a head-up display showing a conventional example.

FIG. 10 is a sectional view of a display device showing a conventional example of the above.

[Explanation of symbols]

11 First liquid crystal display (first display) 12 Second liquid crystal display (second display) 13 Dichroic mirror (transmissive reflection member) 16 Liquid crystal display element 18 Light emitting diode (light emitting element) 33 Liquid crystal display device 35 Light emitting diode (light emitting element) 53 Indicator display (second display) L1 first display light L2 Second display light

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Koichi Katori             1-1 190 Fujihashi, Nagaoka City, Niigata Prefecture Japan             Seiki Co., Ltd. R & D Center (72) Inventor Mitsugu Kobayashi             1-1 190 Fujihashi, Nagaoka City, Niigata Prefecture Japan             Seiki Co., Ltd. R & D Center (72) Inventor Takeshi Ejiri             1-1 190 Fujihashi, Nagaoka City, Niigata Prefecture Japan             Seiki Co., Ltd. R & D Center F term (reference) 2H088 EA23 HA02 HA13 HA21 HA22                       HA28 MA06                 2H091 FA05X FA14X FA15X FA45Z                       LA17 MA03                 3D044 BA22 BA26 BB01 BC25 BD01

Claims (7)

[Claims] 1. A first indicator which emits a first display light,
A second display device that emits a second display light, and a transmissive reflection member that reflects the first display light and transmits the second display light, wherein the transmissive reflection member is , The reflectance is higher than the transmittance in a first wavelength range including the wavelength of the first display light, and the transmittance is higher than the reflectance in a second wavelength range including the wavelength of the second display light. A display device having transmission / reflection characteristics. 2. The liquid crystal display according to claim 1, wherein at least one of the first display and the second display has a liquid crystal display element and a light emitting element that illuminates the liquid crystal display element. A display device characterized by being a container. 3. The display device according to claim 2, wherein the light emitting element is a light emitting diode. 4. The display device according to claim 2 or 3, wherein the liquid crystal display element is a dot matrix type and is driven by a multiple line simultaneous selection driving method. 5. The display device according to claim 2, 3 or 4, wherein the liquid crystal display element displays a moving image. 6. The display device according to claim 1, wherein the first display device is a liquid crystal display device having a liquid crystal display element. 7. The display device according to claim 6, wherein the transmissive / reflecting member transmits infrared rays.