JPH04137325U - display device - Google Patents

Abstract

(57) [Summary] [Purpose] A semi-transmissive mirror arranged at an appropriate angle with respect to the conventional viewing direction, and two mirrors arranged in the transmission direction and reflection direction of this semi-transmissive mirror. In a display device consisting of a front liquid crystal display element, the configuration becomes complicated as it is necessary to attach a polarizing plate to each liquid crystal display element, and the semi-transparent mirror has to be used as a rear mirror. This has led to problems such as double images and poor display quality. [Structure] One surface of the polarizing plate 7 of each liquid crystal display element 4, 5 is arranged on the viewing direction Z side of the semi-transmissive mirror 3 so that it is shared by the two liquid crystal display elements 4, 5. By using the display device 1 as shown in FIG. This is to improve the display quality and solve the problem.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

The present invention relates to a display device used, for example, as an automobile instrument. In detail, a pair of display devices and a semi-transparent mirror are used to display a reflected image and a transmitted image. This relates to a display device.

0002

[Conventional technology]

FIG. 2 shows an example of a conventional display device 90 of this type. The semi-transparent mirror 92 is mounted with an upward tilt of, for example, 45 degrees with respect to the viewing direction Z, and A reflected image liquid crystal display element 93 is provided on the upper surface side of this semi-transmissive mirror 92, and a transmitted image is provided on the back side. A liquid crystal display element 94 is supposed to be attached.

0003 With the above configuration, the display device 90 can turn on the reflective image liquid crystal display element 93. When it is viewed as a reflected image (virtual image) by the semi-transmissive mirror 92, the transmitted image liquid crystal When the display element 94 is turned on, a transmitted image (real image) transmitted through the semi-transparent mirror 92 and When both liquid crystal display elements 93 and 94 are turned on at the same time, The combined image is what is viewed.

0004

[Problem that the idea aims to solve]

However, in the conventional display device 90 described above, both the liquid crystal display When the elements 93 and 94 are, for example, TN liquid crystals, polarizing plates 9 are provided on the front and back surfaces respectively. 5 is required, which increases the number of man-hours and the number of parts, making this type of display device 90 bulky. This results in a problem that the casing 91 is unduly expensive, and the casing 91 does not allow outside air to pass through the opening 91a. Because it is open to the outside, in preparation for cleaning the semi-transparent mirror 92 from dust, The reflective film 92b, which is relatively easily damaged, is placed on the back side of the transparent substrate 92a with respect to the viewing direction. In this case, the reflection image liquid crystal display element 93 side has no choice but to be provided. The image is also reflected on the surface of the transparent substrate 92a, resulting in a double image on the reflected image (virtual image) side. As a result, problems arise that impair display quality, and it is necessary to resolve these problems. It became the subject of discussion.

[0005]

[Means to solve the problem]

The present invention is a specific means for solving the conventional problems mentioned above. A semi-transmissive mirror arranged at an appropriate angle to In the display device comprising two liquid crystal display elements disposed in each direction, The polarizing plate of the liquid crystal display element is shared by the two sides of the liquid crystal display element. A display device characterized in that one surface is arranged on the viewing direction side of a transmitting mirror. By providing this, the above-mentioned conventional problems are solved.

[0006]

【Example】

Next, the present invention will be explained in detail based on an embodiment shown in the drawings. What is indicated by the reference numeral 1 in FIG. 1 is a display device according to the present invention, and this display device 1 is abbreviated as A semi-transparent mirror 3 is tilted upward in a box-shaped housing 2 provided with an opening 2a on the viewing direction Z side. For example, T A reflective image liquid crystal display element 4 of N (twisted nematic) liquid crystal is provided and serves as the back surface. A transmission image liquid crystal display element 5 made of a similar TN liquid crystal is provided on the transmission direction Z side. This is similar to the conventional example.

[0007] However, in the present invention, the bidirectional liquid crystal display elements 4 and 5, that is, the reflective image liquid crystal display elements 4 and 5, The display element 4 and the transmission image liquid crystal display element 5 each include both liquid crystal display elements 4 and 5. As mentioned above, in the case of a TN liquid crystal, a rear polarizing plate is provided on each back side. Only 6a and 6b are installed closely together, and the view is similar to that of the conventional example. It should not be installed closely on the viewing direction side, but should be installed on the viewing direction Z side. The polarizing plate has one front side polarized light on the viewing direction Z side relative to the semi-transmissive mirror 3 of the housing 2. It is supposed to be provided as a plate 7.

[0008] Here, if the front polarizing plate 7 is explained in more detail, this front polarizing plate 7 is provided so as to cover the entire display surface of the display device 1, that is, It is provided so as to cover the opening 2a of the casing 2, and its polarization axis is Orthogonal to the rear polarizing plates 6a and 6b provided on the back side of both the liquid crystal display elements 4 and 5. It is assumed that

[0009] Further, as described above, the opening 2a of the housing 2 is covered by the front polarizing plate 7. This makes it relatively easy to make the inside of the casing 2 a sealed structure, and this The sealed structure also prevents dust from adhering to the semi-transparent mirror 3. Therefore, in the present invention, the semi-transparent mirror 3 allows the reflective film 3a to be viewed from the transparent substrate 3b. It is applied on the Z-direction side, that is, it is a so-called front mirror.

0010 Next, the operation and effects of the display device 1 of the present invention having the above structure will be explained. For example, suppose that the front polarizing plate 7 is provided on the viewing direction Z side of the semi-transmissive mirror 3 according to the present invention. As a result, in the reflected image liquid crystal display element 4 and the transmitted image liquid crystal display element 5, , rear polarizing plates 6a and 6 provided closely on the back sides of the liquid crystal display elements 4 and 5, respectively. b and this front polarizing plate 7 perform the display function, that is, the front polarizing plate 7 It is shared by both the liquid crystal display elements 4 and 5.

[0011] Further, the front polarizing plate 7 is provided on the viewing direction side of the semi-transmissive mirror 3. Therefore, the front polarizing plate 7 can cover the opening 2a of the housing 2 to form a sealed structure. To make it easier, the semi-transparent mirror 3 is provided with a reflective film 3a on the viewing direction Z side of the transparent substrate 3b. It is now possible to use a mirror with a mirror surface applied to the surface of the reflective image liquid crystal display element. The superimposed image passes back and forth through the reflective film 3a with a transmittance of 50%, for example. As a result, the amount of light is greatly attenuated and becomes almost invisible, which makes it difficult to see in real life. This will prevent the occurrence of double images that would be a nuisance to the user.

0012 In the above embodiment, the reflection image liquid crystal display element 4 and the transmission image liquid crystal display element Although the explanation was given using the example of a TN liquid crystal that requires polarizing plates on the front and back surfaces, the present invention This can also be done for GH (guest host) liquid crystals where a polarizing plate is attached only on the direction side. Needless to say, he is talented.

[0013]

[Effect of the idea]

As explained above, with this invention, the polarizing plate of the liquid crystal display element can be used to display two sides of the liquid crystal display. One surface is placed on the viewing direction side of the semi-transmissive mirror so that it is shared by the elements. By making this a display device, the front bias, which was conventionally required for the entire surface of each liquid crystal display element, has been eliminated. This makes it possible to share the light plate, which simplifies the configuration of the display device and reduces the number of parts and labor. This has an excellent effect of making it possible to reduce costs by reducing the number of parts.

[0014] In addition, by configuring the polarizing plate to be placed on the viewing direction side of the semi-transparent mirror, This allows the entire display device to have a sealed structure, preventing dust from adhering to the semi-transparent mirror. A reflective film is placed on the viewing side to prevent mirror surface cleaning and other maintenance. It is possible to use the formed surface mirror, which prevents double images and improves the display. It also has the excellent effect of improving quality.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing an embodiment of a display device according to the present invention.

FIG. 2 is a sectional view showing a conventional example.

[Explanation of symbols]

1...Display device 2... Housing, 2a... Opening 3... Semi-transparent mirror, 3a... Reflective film, 3b... Transparent substrate 4...Reflection image liquid crystal display element 5...Transmission image liquid crystal display element 6a, 6b...Rear polarizing plate 7...Front polarizing plate Z……Viewing direction

Claims (2)

[Scope of utility model registration request] 1. A semi-transmissive mirror disposed inclined at an appropriate angle with respect to the viewing direction, and a two-sided liquid crystal display element disposed in the transmission direction and reflection direction of the semi-transmissive mirror, respectively. In the display device, one surface of the polarizing plate of the liquid crystal display element is disposed on the viewing direction side of the semi-transmissive mirror so as to be shared by the two liquid crystal display elements. display device. 2. The display device according to claim 1, wherein the semi-transmissive mirror has a reflective film formed on the viewing direction side.