JP2003104087A - Displaying device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a displaying device for performing high brightness display with efficient illumination. SOLUTION: This displaying device 3 projects a display image of a liquid crystal display element 3G lighted up by a light emitting diode 3I on a front glass 4 of a vehicle 1 and displays it. A lens array 3J having a projecting part 3N corresponding to the light emitting diode 3I is disposed between the light emitting diode 3I and the liquid crystal display element 3G.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display device, and more particularly to a display device having a light source for illuminating a transmissive display element (for example, a transmissive liquid crystal display element) from behind.

[0002]

2. Description of the Related Art Conventionally, a display device as shown in FIG. 6 has been known, and a liquid crystal display element A in which a polarizing member is attached to the front and rear surfaces of a liquid crystal cell in which liquid crystal is sealed in a pair of translucent substrates. ,
A light source C that is connected to the hard wiring board B and illuminates the liquid crystal display element A is provided, and a display image emitted from the liquid crystal display element A illuminated by the light source C is reflected by a reflecting mirror D, and a vehicle windshield or a semi-transparent plate ( There is a device such as a reflection plate) which projects on the display unit E. Such a display device is called a head-up display.

Since such a display device has a structure for projecting on the display section E, a part of light is transmitted at the time of projection, and it is necessary to project a display image with good contrast even in the daytime. Therefore, it is necessary to illuminate the liquid crystal display element A with a light source having high brightness such as a halogen lamp or a light emitting diode.

[0004]

However, the illumination light from the light source C in such a display device not only passes through the liquid crystal display element A and is projected on the display section E, but also illuminates a portion other than the liquid crystal display element A. There is a problem that a large amount of light is lost before being projected on the display unit E, such as illuminating an extra portion other than the direction of the reflecting mirror D after passing through the liquid crystal display element A. Further, it has been desired to reduce the loss of the illumination light from the light source C to the display unit E, that is, the unnecessary illumination that illuminates other than the display unit E as described above, and improve the illumination efficiency.

Therefore, the present invention has been made in view of the above-mentioned problems, and its main object is to provide a display device for displaying a high brightness with efficient illumination.

[0006]

According to a first aspect of the present invention, a display device is mounted on a vehicle and a display image of a transmissive display element illuminated by a light source is displayed on a windshield or a reflection of the vehicle. A display device for projecting and displaying on a plate, characterized in that a lens having a convex shape corresponding to the light source is provided between the light source and the transmissive display element.

In the display device of the present invention, as described in claim 2, a transmissive display element that is illuminated from the back surface side and emits a display image from the front surface side, and is illuminated at a predetermined interval from the transmissive display element. And a lens disposed between the transmissive display element and the light source and having a convex shape corresponding to the light source.

According to a third aspect of the present invention, in the display device according to the first or second aspect, the light source is composed of a plurality of light emitting diodes arranged close to each other, and the lens is each light source. It is characterized by having a plurality of convex shapes corresponding to.

Further, as described in claim 4, in the display device according to any one of claims 1 to 3,
A tubular reflecting member is provided between the lens and the transmissive display element.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will now be described with reference to the accompanying drawings, taking as an example a vehicle head-up display for displaying vehicle speed, engine speed, etc.

FIG. 1 shows a vehicle head-up display mounted on a vehicle, and a display image projected by a display device 3 provided on an upper portion of a dashboard 2 of the vehicle 1 is
The surface of the windshield 4 reflects in the direction of the observer 5. The observer 5 can observe the displayed image as a virtual image V by superimposing it on the landscape.

Further, the display device 3 according to the embodiment of the present invention is provided with a concave mirror 3B and a liquid crystal display 3C in a housing 3A provided so as to be embedded in the upper portion of the dashboard 2, and FIG. Explain.

The housing 3A is made of a light-shielding synthetic resin material, is provided with an opening 3D for opening an upper portion (on the windshield side) of the position where the concave mirror 3B is arranged, and sunlight is liquid crystal in the housing 3A. A light-shielding wall 3E that prevents the virtual image V from becoming hard to see (washout) when entering the display 3C is provided, and in this embodiment, it is formed integrally with the housing 3A. The housing 3A is made of a transparent synthetic resin material (eg, acrylic).
The translucent cover 3F made of is provided to cover the opening 3D.

The concave mirror 3B reflects the display light projected from the liquid crystal display 3C to the windshield 4 side, and is provided so that the angle can be adjusted so that the observer 5 can easily visually recognize the display image.

The liquid crystal display 3C projects the display image of the transmissive display element onto the windshield via the concave mirror 32, and as shown in FIG. 2, the liquid crystal display element (transmissive display element) 3G. , A cylindrical reflecting member 3H, a light emitting diode (light source) 3I, and a lens array (lens) 3J.

The liquid crystal display element 3G is a liquid crystal cell in which liquid crystal is sealed in a pair of translucent substrates and polarizing members are attached to the front and rear surfaces thereof. Further, the liquid crystal display element 3G drives a liquid crystal based on a calculation circuit (not shown) that measures the vehicle speed and the engine speed based on the output signals from the vehicle speed sensor and the engine speed sensor provided in the vehicle 1. A liquid crystal drive circuit (not shown) for displaying the measured values of the speed of the vehicle 1 and the engine speed as numerical values.

The tubular reflecting member 3H is formed of a white synthetic resin material in a tubular shape with both ends open, and one opening (opening on the concave mirror side) 3K is closed by the liquid crystal display element 3G. It is arranged.

The light emitting diode 3I is a tubular reflecting member 3K.
A plurality of narrow directivities (20 to 30 degrees in the present embodiment) provided on the other opening 3L side of
The illumination light is fixedly arranged on the hard wiring board 3M in the direction in which the illumination light passes through the inside of the tubular reflecting member to illuminate the liquid crystal display element 3G. The light emitting diodes 3I are preferably arranged at equal intervals on the wiring board 3M so as to prevent uneven illumination. In this case, the light emitting diodes 3I are arranged at equal intervals so as to be closely packed as shown in FIG. ing.

The lens array 3J is made of a translucent synthetic resin material (for example, acrylic), and has spherical convex portions (convex shapes) 3N facing the respective positions of the plurality of light emitting diodes 3I. And the cylindrical reflecting member 3H
And the light emitting diode 3I. The convex shaped portion 3N refracts the illumination light from the light emitting diode 3I to generate illumination light having a narrower directivity, and the liquid crystal display element 3G.
Can be illuminated (shown in FIG. 4). Since the convex portion 3N of the lens array 3J is desired to have a shape such that the illumination light is emitted in a direction substantially perpendicular to the lens array 3J, the degree of directivity of the light emitting diode 3I and the lens array from the light emitting diode 3I are arranged. It is formed in a shape having a curvature and a size according to the disposition distance up to 3J.

In the structure of the display device 3 as described above, the display device 3 displays the display image of the liquid crystal display element 3G illuminated by the light emitting diode 3I on the windshield 4 of the vehicle 1 and displays the light emitting diode 3I and the liquid crystal. The convex portion 3 is provided between the display element 3G and the light emitting diode 3I.
By including the lens array 3J having N,
Illumination light from the light emitting diode 3I is refracted by the convex portion 3N of the lens array 3J, and most of the illumination light illuminates the liquid crystal display element 3G in a state where the directivity is high, and thus illuminates extra parts such as other parts. As a result, it is possible to provide efficient illumination with reduced occurrence and display a display image with high brightness to the observer.

Further, the lens array 3J has a plurality of convex portions 3N corresponding to the respective light emitting diodes 3I by using a plurality of light emitting diodes 3I arranged close to each other as a light source. Even if the light source has such a high directivity, the convex shaped portion 3N refracts the illumination light that does not reduce the directivity and illuminates the direction other than the direction of the liquid crystal display element 3G, which is the low brightness portion, to display the liquid crystal. Since the correction is performed in the direction of the element 3G, uneven illumination is reduced on the surface of the liquid crystal display element.

Further, the lens array 3J and the liquid crystal display element 3
By providing the tubular reflecting member 3H between G and
In the illumination light up to the liquid crystal display element 3G, it is possible to reduce the illumination of an unnecessary portion due to irregular reflection of the lens array 3J and the like, and to reflect the illumination light in the cylinder to obtain the illumination light of the liquid crystal display element 3G. You can
The display device has efficient illumination.

The lens array 3J in the embodiment of the present invention has been described by taking as an example a lens array 3J having a convex shape so as to face the light emitting diode 3I serving as a light source.
The present invention is not limited to this. For example, FIG.
A lens array 31J having a convex portion 31N on the opposite side to the light source 31I as shown in (a) may be used, or as shown in FIG. 5 (b), convex portions 32N may be provided on both surfaces of the lens array 32J. May be provided, and the same effect as that of the above-described embodiment can be obtained. Further, the convex shape of the lens of the present invention is not limited to the spherical surface, and the convex shape of FIG.
It may be a lens array 33J in which a convex portion 33N having a refracting surface N is formed as shown in (C).

Further, although the liquid crystal display element is used as the transmissive display element in the embodiment of the present invention, it may be an electrochromic element, for example. The light source may be a point light source such as a bulb or a linear light source such as a cold cathode fluorescent lamp, but the effect is large as long as it has high directivity.

Further, the display image projected by the display device 3 according to the embodiment of the present invention has been described by taking the structure in which the windshield 4 is reflected in the direction of the observer 5 as an example, but not the windshield 4. , Dashboard 2 and housing 3
The structure may be such that the display image is reflected in the direction of the observer by a hard reflection plate fixedly provided at A and provided exclusively for it, or a translucent reflection plate attached to the inner surface of the windshield 4. .

[0026]

The present invention relates to a display device for displaying a display image of a transmissive display element illuminated by a light source by projecting it on a windshield surface or a reflector of a vehicle and displaying it with efficient illumination and high brightness. It is possible to provide a display device for performing.

[Brief description of drawings]

FIG. 1 is a side view of a vehicle showing an embodiment of the present invention.

FIG. 2 is a sectional view of the display device showing the embodiment.

FIG. 3 is a perspective view showing a hard wiring board, a light emitting diode, and a lens array according to the embodiment.

FIG. 4 is a sectional view of a lens array showing the embodiment.

FIG. 5 is a sectional view of a lens array showing another example of the embodiment.

FIG. 6 is a side view of a liquid crystal display device showing a conventional example.

[Explanation of symbols]

1 vehicle 3 display devices 3C liquid crystal display 3G liquid crystal display element (transmissive display element) 3H cylindrical reflection member 3I Light emitting diode (light source) 3J lens array (lens) 3N convex shape part 4 windshield

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) G03B 21/00 G03B 21/00 E 21/14 21/14 A G09F 9/00 359 G09F 9/00 359Z 9 / 35 9/35 F term (reference) 2H088 EA12 EA23 HA21 HA25 HA28 MA06 2H091 FA17X FA29Z FA45Z FB03 FD05 FD12 FD13 LA16 MA03 3D044 BA22 BA27 BC25 BD01 5C094 AA10 BA43 HA05 5G435 AA03 BB12 DD17 BB17 0619

Claims (4)

[Claims] 1. A display device mounted on a vehicle for projecting and displaying a display image of a transmissive display element illuminated by a light source on a windshield or a reflector of the vehicle, the light source and the transmissive display. A display device comprising a lens having a convex shape corresponding to the light source between the element and the element. 2. A transmissive display element that is illuminated from the back surface side and emits a display image from the front surface side, a light source that illuminates the transmissive display element at a predetermined interval, and between the transmissive display element and the light source. A display device, comprising: a lens provided and having a convex shape corresponding to the light source. 3. The light source comprises a plurality of light emitting diodes arranged in close proximity, and the lens has a plurality of convex shapes corresponding to the respective light sources. Item 3. The display device according to item 2. 4. The display device according to claim 1, further comprising a tubular reflecting member provided between the lens and the transmissive display element.