JP3451387B2 - Aerial display device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improved invention for an aerial information display device, and more particularly to an aerial display device.

[0002]

2. Description of the Related Art The inventors of the present invention have previously proposed an invention which is an information aerial display device. This is to map the light emitting surface of a projector (for example, an electroluminescent display) into the air as a real image of an erecting equal-magnification by the gradient index lens element,
The display device was such that the observer could see the real image (see Japanese Patent Application No. 7-215108).

In this information aerial display device, if the distance from the image-side end surface (upper end surface) of the gradient index lens element to the real image in the air is long, that is, if an object is mapped to a long distance, The distance from the light emitting surface of the projector, which is an object, to the other end surface (lower end surface, that is, the object side end surface) of the gradient index lens element also needs to be increased corresponding to the distance. Therefore, there is a problem in that the vertical dimension of the information aerial display device, that is, the size from the display (projector) as an object toward the gradient index lens element is unavoidable.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems of the prior art. The object of the present invention is to measure the vertical dimension of a conventional information aerial display device. The present invention is intended to provide an aerial display device capable of reducing the size.

[0005]

The aerial display device according to the present invention achieves the above-mentioned object and is as follows.

According to a first aspect of the present invention, in a display device including the display and the gradient index lens element, the display screen can be mapped by the gradient index lens element as a real image of an erecting equal magnification. The light beam emitted from the display screen is incident on the end surface of the gradient index lens element through the reflection of at least one mirror, is emitted from the other end surface of the gradient index lens element, and is a real image in the air. The display, the at least one mirror and the gradient index lens element are provided at predetermined positions so that an image can be formed.

According to a second aspect of the present invention, in the aerial display device according to the first aspect, a plurality of microlens plates in which a plurality of micro-convex lenses are arranged are used instead of the gradient index lens element. The object is erected by aligning the optical axes of the micro-convex lenses between the micro-lens plates, that is, by arranging the micro-convex lenses so that they have a common optical axis, and by arranging them at a predetermined interval. The lens member is used so that an image can be formed at the same magnification.

[0008]

The lens member composed of the gradient index lens element or the plurality of microlens plates forms an object at a predetermined position on the predetermined position as an erecting equal-magnification image. The distance (object-side working distance) from this object to the end surface of the gradient index lens element or a lens member (hereinafter also referred to as a microlens plate member) including a plurality of microlens plates and the gradient index lens element or the micro The distance from the other end surface of the lens plate member to the image (image-side working distance) has a predetermined value depending on the gradient index lens element or the microlens plate member.

Since the gradient index lens element and the microlens plate member have the same function, the function of the present invention will be described below by taking the gradient index lens element as a representative.

FIG. 3 is a schematic diagram showing the structure of a conventional information aerial display device. Thus, the vertical size h of the conventional information aerial display device is determined by the object-side working distance described above. If the real image 4 is made to float further, that is, L is moved to a position further away from the gradient index lens element 3.
In order to map the CD screen 1, it is necessary to increase the size of the housing 6 in the vertical direction. In the present invention, the vertical distance from the object to the gradient index lens element or the mirror is shortened by utilizing the reflection of the mirror.

Assuming that the light beam emitted from the object is reflected by one mirror and is incident on the end surface of the gradient index lens element, the traveling distance of the light beam is the object side working distance itself. Of course, in the conventional information aerial display device, the object-side working distance is a factor that determines the length of the device in the vertical direction. On the other hand, in the aerial display device according to the present invention, the distance from the object to the mirror or the distance from the mirror to the gradient index lens element is a factor that determines the length in the vertical direction of the device. It is obvious that the distance from the object to the mirror and the distance from the mirror to the end surface of the gradient index lens element are shorter than the working distance on the object side.

By increasing the number of mirrors and reflecting the light rays by the number of the mirrors to guide the light rays from the object to the end surface of the gradient index lens element, the vertical size of the display device can be further shortened. .

[0013]

1 is a schematic view showing an embodiment of an aerial display device according to the present invention. A person skilled in the art can appropriately select what is used as the display device, but the LCD 7 is used here.

A light beam emitted from the LCD screen 1 which is an object is reflected by a mirror 2a, and a light beam reflected by the mirror 2a is reflected by a mirror 2b, and a gradient index lens element as an erecting equal-magnification image forming means. It is incident on the object-side end surface 3a of the laser beam 3. The light ray incident on the gradient index lens element 3 travels in the gradient index lens element 3 while meandering, exits from the image side end surface 3b, and forms an image at a predetermined position. The observer can see the real image 4 in the air.

The LCD screen 1 is emitted and the mirror (2
a, 2b) and the trajectory of the light ray until reaching the real image through the gradient index lens element 3 are shown by a chain double-dashed line.

The gradient index lens element 3 is a lens member in which gradient index rod lenses of an optical fiber are arranged in a matrix, and an object at a predetermined position, that is, an object side working distance is placed at a predetermined position, that is, an image side working distance. Map to.

As shown in FIG. 1, it is obvious that the vertical size h of the aerial display device is shorter than that in the case of FIG. 3 without the mirrors (2a, 2b). Although two mirrors (2a, 2b) are used in FIG. 1, the number of mirrors is determined by a person skilled in the art in consideration of the vertical size h of the aerial display device. That is something to be done.

FIG. 2 is a schematic view showing an embodiment of the aerial display device according to the present invention. In FIG. 2, a member corresponding to the housing 6 of FIG. 1 is omitted. In this way, the size of the aerial display device in the vertical direction can be shortened even with one mirror 2a. From FIGS. 1 and 2, it is apparent that the size of the aerial display device according to the present invention becomes smaller in the vertical direction and larger in the horizontal direction as the number of mirrors is increased. If the size in the vertical direction can be reduced, the depth of the aerial display device will be reduced, so various structures,
For example, it becomes easy to embed the aerial display device on a wall, a table, or the like.

FIG. 4 is a schematic view showing an embodiment of the aerial display device according to the present invention. In FIG. 4, three microlens plates (5a, 5b, 5c) are used instead of the gradient index lens element of FIG.

The microlens plate is a lens member formed by arranging a large number of micro-convex lenses. Each micro-convex lens has a function equivalent to that of a normal convex lens and maps an object at a predetermined position as an inverted real image. . In this microlens plate, the optical axes of the respective micro-convex lenses are made to coincide between the respective microlens plates, and the microlens plates are arranged in parallel at a predetermined interval.
For example, by arranging three lenses, the same function as that of the gradient index lens element can be provided. That is, the object at the predetermined position can be transmitted to the predetermined position as an erecting equal-magnification image.

[0021]

Since the present invention is constructed as described above, it has the following effects. A plurality of microlens plates are formed so that the rays emitted from the screen of the display device, which is an object, are reflected by the number of mirrors that set up the rays and the gradient index lens element or the object can be imaged at an equal magnification. It is possible to provide an aerial display device in which the vertical size of the display device can be made shorter than that of the conventional aerial information display device, since the light is incident on the end surface of the lens member in which the is arranged.

[Brief description of drawings]

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

FIG. 2 is a schematic diagram showing an embodiment of an aerial display device according to the present invention.

FIG. 3 is a schematic diagram showing a configuration of a conventional information aerial display device.

FIG. 4 is a schematic diagram showing an embodiment of an aerial display device according to the present invention.

[Explanation of symbols]

1 LCD screen 2a, 2b mirror 3 Gradient index lens element 3a Object side end face 3b Image side end face 4 real image 5a Micro lens plate for inversion 5b Micro lens plate for adjusting the traveling direction of light rays 5c Micro lens plate for re-inversion 6 housing 7 LCD 8 Micro lens plate holding frame h Vertical size of aerial display device (outside size)

─────────────────────────────────────────────────── --- Continuation of the front page (56) References JP-A-1-92784 (JP, A) JP-A-5-188340 (JP, A) JP-A-9-34389 (JP, A) JP-A-8- 50285 (JP, A) JP-A-5-158011 (JP, A) JP-A-4-298710 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) G09F 9/00 G02B 3 / 00 G02B 27/02

Claims (2)

(57) [Claims] 1. A display device comprising the display and the gradient index lens element, wherein the display screen can be mapped by the gradient index lens element as a real image of an erecting equal size magnification. The incident light beam can enter the end surface of the gradient index lens element through reflection of at least one mirror, exit from the other end surface of the gradient index lens element, and be imaged in the air as a real image. Thus, the aerial display device characterized in that the display, the at least one mirror and the gradient index lens element are provided at predetermined positions. 2. A plurality of microlens plates in which a plurality of micro-convex lenses are arranged are provided in place of the gradient index lens element, and an optical axis of the micro-convex lenses is provided between the plurality of micro-lens plates. The aerial display device according to claim 1, wherein a lens member is used which is capable of forming an image at an erecting equal-magnification ratio by arranging the lens elements with each other at a predetermined interval.