KR101976278B1 - Super multiview tabletop display device - Google Patents

Abstract

Disclosed is a super multi-view tabletop display device. According to the present invention, the super multi-view tabletop display device outputs an image in an integrated image manner through a screen provided on an upper surface of a table in which an internal space is formed, and comprises: an image output device disposed on the bottom surface of the table and outputting light source including image information in the screen direction; a telecentric lens group provided between the screen and the image output device and consisting of a first lens having a positive refractive power and a second lens having a negative refractive power, wherein the first and second lenses are sequentially disposed from the image output device toward the screen; a field lens disposed between the telecentric lens group and the screen, and enabling the light source passed through the telecentric lens group to be incident to the screen at a predetermined angle; and a micro-lens array disposed on an upper portion of the screen and consisting of a hemispherical micro-lens unit to which the light source passed through the screen is incident. Thus, a multi-view image with reduced chromatic aberration is provided while durability is improved.

Description

{SUPER MULTIVIEW TABLETOP DISPLAY DEVICE}

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to an ultra-multi-viewpoint tabletop display device, and more particularly, to a tabletop display device capable of viewing an image projected on an upper surface of a table without distortion in all directions.

Projection display technology is attracting attention because it can achieve a large screen aspect ratio at a relatively low price.

[0002] A known projection system is a device for emitting an image signal to light emitted from a light emitting device and projecting the image signal on the front or rear surface of the screen to view the image. The CRT method, the DMD (Digital Micromirror Device) , A reflective liquid crystal panel method, and a transmissive liquid crystal panel method. Recently, a three-dimensional projection system for displaying a 3D image has been developed.

Conventionally, a three-dimensional projection system is mainly used for a display device that projects an image on a rotatable screen using a high-speed driven image display device such as a digital micro mirror device (DMD). At this time, the high-speed driving image display element and the rotatable screen are driven in synchronization, and the screen serves to refract the direction of the projected light. Thus, as the screen rotates, an image passed through the screen can be viewed in a 360 degree direction.

However, the conventional table top display has a disadvantage in that the projection optical system has a long length, that is, the distance from the floor to the table top surface, that is, the height of the table, has to be designed to be too high and the viewing angle is narrow and the size of the display is small, have.

Korean Patent No. 10-1617656 Korean Patent Publication No. 10-2015-0091838

One aspect of the present invention provides a super multi-viewpoint tabletop display device capable of enlarging a display size by using a plurality of projectors while allowing a three-dimensional image obtained by integrating images on a table top to be viewed without distortion in all directions .

The technical problem of the present invention is not limited to the technical problems mentioned above, and other technical problems which are not mentioned can be understood by those skilled in the art from the following description.

The super high score table top display apparatus according to an embodiment of the present invention is a super high score table top display apparatus for outputting an image in an integrated image format through a screen installed on a top surface of a table on which an inner space is formed, An image output device disposed on a bottom surface and outputting a light source including image information in the screen direction; a display device, disposed between the screen and the image output device, for outputting a positive refracting power And a second lens having a negative refracting power, wherein the telecentric lens group is provided between the telecentric lens group and the screen, and the light source passing through the telecentric lens group is a predetermined A field lens arranged to be incident on the screen at an angle, And a microlens array composed of a hemispherical microlens unit through which a light source passed through the screen is incident.

The first lens and the second lens may be provided such that both surfaces thereof have a meniscus shape convex in the screen direction.

Wherein the first lens has a meniscus shape with a positive refractive power and a curvature radius of a lower surface of the second lens is larger than a curvature radius of the upper surface and the second lens has a meniscus shape with a negative refracting power, And the radius of curvature of the lower surface is smaller than the radius of curvature of the upper surface.

Wherein a radius of curvature of the lower surface of the first lens is 30.47 mm to 30.57 mm, a radius of curvature of the upper surface of the first lens is 16.94 mm to 16.99 mm, a radius of curvature of the lower surface of the second lens is 16.514 mm to 16.574 mm, And the radius of curvature of the upper surface of the second lens is 23.451 mm to 23.551 mm.

Wherein the first lens and the second lens are in contact with each other so that the center of the upper surface of the first lens and the center of the lower surface of the second lens are spaced by a minute distance, aperture of the first lens is the same as the lens diameter of the lower surface of the second lens and the radius of curvature of the upper surface of the first lens is larger than the radius of curvature of the lower surface of the second lens.

The telecentric lens group can correct the chromatic aberration by limiting the field size of the light source output from the image output device to a predetermined size or less.

And the predetermined size is a length of the width of the field lens.

Wherein the screen includes an optical glass having a predetermined thickness and a film screen attached to an upper surface of the optical glass to scatter a light source that has passed through the optical glass, wherein the field lens is provided on a lower surface of the optical glass, And may have a convex shape toward the video output device.

A plurality of projection optical systems including the image output device, the telecentric lens, and the field lens may be provided in the table, and one of the projection optical systems may be disposed apart from the adjacent projection optical system by a predetermined distance.

The projection optical system of any one of claims 1 to 3, wherein the projection optical system is disposed at a predetermined distance from the adjacent projection optical system, wherein a first field lens constituting one of the projection optical systems and a second field lens constituting the adjacent projection optical system are spaced apart from each other by a predetermined distance And are spaced apart from each other by a distance.

The predetermined angle may be not less than a minimum angle calculated based on the thickness of the screen and the spacing distance, and is not greater than a maximum angle calculated based on a scattering angle of the screen and a viewing angle of the screen.

The minimum angle may be calculated through the following equation.

Here,? _Min is the minimum angle, t is the thickness of the screen, and? Is the separation distance.

The maximum angle may be calculated by the following equation.

Where θ _max is the maximum angle, θ _d is the scattering angle of the screen, and θ _FOV is the viewing angle of the screen.

The microlens unit may be an aspherical lens having a convex curved surface in the screen direction and a flat back surface.

An optical mask having a blocking region and a transmissive region is attached to the rear surface of each of the microlens units, and only a part of the light source, which is incident on the microlens unit by the optical mask, .

An interval between the image projection device and the telecentric lens group is 17.53 mm to 17.63 mm and an interval between the telecentric lens group and the field lens is 155.1 mm to 155.3 mm.

According to one aspect of the present invention, because of the structural features of the lenses constituting the telecentric lens group, it is possible to provide a multi-view image in which chromatic aberration is reduced while durability is improved, Thereby enlarging the display size.

FIG. 1 is a diagram illustrating a schematic configuration of a super multi-viewpoint tabletop display device according to an embodiment of the present invention.
Figs. 2 to 6 are views showing a specific configuration of the telecentric lens group of Fig. 1. Fig.
Figs. 7 and 8 are views showing a specific configuration of the field lens of Fig. 1. Fig.
Figs. 9 and 10 are views showing a specific configuration of the screen of Fig.
Figs. 11 and 12 are views showing a specific configuration of the microlens array of Fig. 1. Fig.
Figs. 13 and 14 are diagrams showing a configuration of an ultra-high-resolution table top display apparatus having a plurality of projection optical systems.

The following detailed description of the invention refers to the accompanying drawings, which illustrate, by way of illustration, specific embodiments in which the invention may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention. It should be understood that the various embodiments of the present invention are different, but need not be mutually exclusive. For example, certain features, structures, and characteristics described herein may be implemented in other embodiments without departing from the spirit and scope of the invention in connection with an embodiment. It is also to be understood that the position or arrangement of the individual components within each disclosed embodiment may be varied without departing from the spirit and scope of the invention. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present invention is to be limited only by the appended claims, along with the full scope of equivalents to which such claims are entitled, if properly explained. In the drawings, like reference numerals refer to the same or similar functions throughout the several views.

Hereinafter, preferred embodiments of the present invention will be described in more detail with reference to the drawings.

FIG. 1 is a diagram showing a schematic configuration of a super-multi-view tabletop display device 1 according to an embodiment of the present invention.

The ultra-high-resolution table top display apparatus 1 according to the present invention includes a table top which outputs an image by an integral imaging method and outputs a three-dimensional image by integrating a light source in a predetermined space above the table ) Display device.

In detail, the ultra-high-resolution table top display apparatus 1 according to an embodiment of the present invention includes a video output apparatus 100, a telecentric lens group 200, a field lens 300, a screen 400, And includes a microlens array 500.

As shown in the figure, the table 50 is a box-shaped housing having a space formed therein. The top surface of the table 50 is provided with a screen 400 disposed parallel to the top surface, a microlens array 500 provided on the top of the screen 400, May be provided. The image output device 100, the telecentric lens group 200, and the field lens 300 may be sequentially disposed in the empty space inside the table 50 from the bottom surface.

The video output apparatus 100 is an apparatus for outputting a light source including video information, and may be, for example, a projector. The image output apparatus 100 may be disposed on the bottom surface of the table 50 to output the light source in the direction of the top surface of the table 50, that is, the direction in which the screen 400 described later is formed.

In this case, when the super-multi-view tabletop display device 1 according to the present invention provides a three-dimensional image, the image output apparatus 100 may output an elemental image as image information. The elemental image can be defined as an image of an object to be displayed through a lens array composed of a plurality of lenses. The image output apparatus 100 outputs an elemental image array, which is a set of elemental images, and the output elemental image arrays are integrated through a microlens array 500, which will be described later, have. A method of generating an element image and a method of displaying a three-dimensional image through an element image arrangement are well known techniques in the field of display of an integrated image system, and thus a detailed description thereof will be omitted.

The telecentric lens group 200 is installed on the image output device 100 and can transmit the light source output from the image output device 100 to the field lens 300. [ In this process, the telecentric lens group 200 can adjust the traveling path of the light source output from the image output apparatus 100 to be directed to the upper side of the table 50.

The telecentric lens group 200 may include a first lens 210 and a second lens 220. The first lens 210 may be a convex lens having a positive refractive power and the second lens 220 may be a concave lens having a negative refractive power. The overall field size of the light source may be limited while sequentially passing through the first lens 210 and the second lens 220. [ Here, the field size is defined as the area where the light source is projected.

Although the first lens 210 and the second lens 220 are shown as being spaced apart from each other for the sake of convenience of explanation, the first lens 210 and the second lens 220, The lens 220 can be designed and arranged such that the both ends thereof are in contact with each other and the central part is spaced apart by a predetermined distance. Accordingly, an internal space may be provided between the first lens 210 and the second lens 220. The specific configuration and function of the telecentric lens group 200 including the first lens 210 and the second lens 220 will be described later with reference to FIG.

The field lens 300 may be installed on top of the telecentric lens group 200. Specifically, the field lens 300 may be provided in a space between the telecentric lens group 200 and the screen 400.

Particularly, the field lens 300 according to the present invention may be installed on the lower surface of the screen 400 so that the light source passing through the telecentric lens group 200 can be incident on the screen 400 at a predetermined angle. That is, the field lens 300 can control the path of the light source incident on the field lens 300 such that the direction of the light source incident on the screen 400 is similar to the direction of the optical axis (OX). To this end, the field lens 300 has a convex shape on the front side facing the telecentric lens group 200 side, and a convex-plano lens having a flat shape on the back side toward the screen 400 side. ). ≪ / RTI >

The screen 400 may be installed on the top of the table 50, specifically, in a direction parallel to the top surface of the table, i.e., perpendicular to the optical axis OX. A field lens 300 may be disposed on the lower surface of the screen 400 and a microlens array 500 may be disposed on the upper surface of the screen 400. The screen 400 may transmit the light source that has passed through the field lens 300 to the top of the table 50. At this time, the screen 400 may be designed to have a predetermined scattering angle and viewing angle so as to scatter the incident light source.

The microlens array 500 may be installed on the top of the screen 400. The microlens array 500 may be a two-dimensionally arrayed microlens unit 510 that integrates light sources scattered in the course of passing through the screen 400 into a predetermined space above the table 50. The microlens unit 510 may be a semi-spherical optical lens having a convex curved surface in the screen direction, as shown in partial enlarged view B.

Hereinafter, each component constituting the ultra-high-resolution table top display apparatus 1 shown in FIG. 1 will be described in detail.

2 to 6 are views showing the specific structure of the telecentric lens group 200 of FIG.

As described above, the telecentric lens group 200 may include a first lens 210 and a second lens 220. More specifically, in an ultra-high-resolution table top display apparatus 1 according to the present invention, the first lens 210 and the second lens 220 are sequentially disposed along the optical axis OX from the image output apparatus 100 side .

The first lens 210 may have a positive refractive power and be designed to have a meniscus shape. That is, the first lens 210 is provided such that the lower surface 211 and the upper surface 212 have a crescent shape having a convex shape in the direction of the screen 400. When the curvature radius of the lower surface 211 has a positive refractive power, May be designed to be larger than the radius of curvature of the second portion (212). The radius of curvature of the lower surface 211 of the first lens 210 is 30.47 mm to 30.57 mm and the radius of curvature of the upper surface 212 of the first lens 210 is designed to be 16.94 mm to 16.99 mm . The specific shape and detailed specifications of the first lens 210 including the same are shown in FIGS. 3 and 4. FIG.

The second lens 220 may be designed to have a meniscus shape having a negative refractive power. Similar to the first lens 210, the second lens 220 has a lower surface 221 and an upper surface 222 so as to have a crescent shape having a convex shape in the direction of the screen 400. However, when the second lens 220 has a negative refractive power 221 may be designed so that the radius of curvature of the second lens 220 is smaller than the radius of curvature of the upper surface 222. In this embodiment, the radius of curvature of the lower surface 221 of the second lens 220 is 16.514 mm to 16.574 mm, The radius of curvature of the upper surface 222 of the lens 220 is designed to satisfy 23.451 mm to 23.551 mm. The specific shape and detailed specifications of the second lens 210 including the same are as shown in Figs. 5 to 6.

Meanwhile, in the telecentric lens group 200 according to the present embodiment, both ends of the first lens 210 and the second lens 220 may be arranged to be in contact with each other. That is, the edge of the upper surface 221 of the first lens 210 may be arranged to be in contact with the edge of the lower surface 222 of the second lens 220. Due to the structural features of the first lens 210 and the second lens 220 described above, the center of the upper surface 221 of the first lens 210 formed on the optical axis OX and the center of the upper surface 221 of the second lens 220 The center of the lower surface 222 may be spaced apart by a predetermined distance. In other words, a gap may be formed between the first lens 210 and the second lens 220. The structure of the first lens 210 and the second lens 220, The gap formed according to the characteristic may be formed to have a depth of 0.399 mm to 0.499 mm in the central portion and become narrower toward the outer side.

In addition, due to the gap formed between the first lens 210 and the second lens 220, the durability of the ultra-high-resolution table top display apparatus 1 according to the present invention can be improved. When heat is applied to the lens that transmits the image, the lens area expands according to the thermal expansion coefficient depending on the material of the lens, and accordingly, A change occurs in the refracting power of the lens. This may cause a problem that the image formed on the screen is distorted or the chromatic aberration is increased unlike the originally designed.

On the other hand, since the telecentric lens group 200 according to the present invention is designed such that the edge surfaces of the first lens 210 and the second lens 220 are attached to each other, the effect of suppressing mutual expansion due to heat generation . When the first lens 210 and the second lens 220 are designed to be completely attached to each other, the thermal expansion coefficients of the first lens 210 and the second lens 220 are different from each other, A crack may be generated due to the expansion of the lens, resulting in a problem of poor durability. However, according to the present invention, a gap according to a structural characteristic is formed between the first lens 210 and the second lens 220, so that even when heat is applied to the telecentric lens group 200, .

As described above, the telecentric lens group 200 according to the present invention can be composed of the first lens 210 and the second lens 220 having a negative refracting power. The light source output from the image output apparatus 100 sequentially passes through the first lens 210 having a positive refractive power and the second lens 220 having a negative refractive power so that a field size (wide angle) is limited and chromatic aberration is reduced . In addition, the light sources incident on the first lens 210 and the second lens 220 may be designed to have a meniscus shape so as not to be totally reflected.

FIG. 7 is a diagram showing the specific structure of the field lens 300 and the screen 400 of FIG.

The field lens 300 is provided on the lower surface of the screen 400 and allows the light source passing through the telecentric lens group 200 to enter the screen 400. [ The field lens 300 has a convex shape on the front side facing the direction of the telecentric lens group 200 and a convex-plano lens having a flat shape on the rear side facing the side of the screen 400 The specific specification of the field lens 300 is as shown in Fig.

The field lens 300 can control the path of the light source that is incident on the field lens 300 so that the traveling direction of the light source incident on the screen 400 is similar to the direction of the optic axis OX. The light source passing through the field lens 300 may be incident on the screen 400 at an angle of about 90 with an incident angle of 85 ° to 95 ° when the light is incident on the screen 400.

The screen 400 is installed on the upper surface of the table 50. The field lens 300 is disposed on the lower surface and the microlens array 500 is disposed on the upper surface. The screen 400 may include an optical glass 410 and a film screen 420.

The optical glass 410 may transmit a light source that has passed through the field lens 300 to the film screen 420. The optical glass 410 supports the film screen 420 and is designed to have a predetermined thickness to ensure the distance between the film screen 420 and the field lens 300. The film screen 420 may be a thin film screen attached to the upper surface of the optical glass 410, and may scatter light passing through the optical glass 410. The detailed specifications of the optical glass 410 and the film screen 420 are as shown in FIG.

10 is a view showing a specific structure of the microlens array 500 of FIG.

The microlens array 500 is installed on the upper part of the film screen 420 and can condense the light sources scattered by the film screen 420 into a space above the table 50 to display a three- The lens array 500 may be in the form in which the microlens units 510 are two-dimensionally arranged.

The microlens unit 510 may have a convex shape in the direction of the screen 400, and the back surface may be a hemispherical optical lens having a flat shape. The microlens unit 510 can transmit a light source incident on a lower surface having a convex surface to an upper surface having a flat surface. At this time, an optical mask 520 may be attached to the upper surface of each microlens unit 510.

The optical mask 520 may be formed so as to correspond to the upper shape of the microlens unit 510 as a whole. A through hole may be formed at the center of the optical mask 520. The light source that is directed to the center of the upper surface of the microlens unit 520 is transmitted to the upper portion of the table 50 and the light source that is directed to the peripheral portion of the upper surface of the microlens unit 520 The specific shape of the microlens array 500 is as shown in FIG. 11, and the detailed specification of the microlens array 500 is as shown in FIG.

In the meantime, the super-multi-view tabletop display device 1 according to the present invention may include a plurality of image output devices 100, a telecentric lens group 200, and a field lens 300. In this regard, For convenience of explanation, the configuration including the video output device 100, the telecentric lens group 200, and the field lens 300 will be described as one projection The optical system 1000 will be described.

Referring to Fig. 13, there is shown a schematic configuration of an ultra-high resolution table top display apparatus 1 'composed of a plurality of projection optical systems 1000. Fig.

That is, a plurality of projection optical systems 1000 may be disposed in the table 50 in the ultra-high-resolution table top display apparatus 1 'according to the present invention. The center of the video output device 100 constituting each projection optical system 1000, the center of the telecentric lens group 200 and the center of the field lens 300 are formed on the same straight line (optical axis) The straight line (optical axis) may be formed in a direction perpendicular to the bottom surface of the table 50.

Each of the projection optical systems 1000 may be disposed at a distance from the adjacent projection optical system 1000 '. Specifically, one of the field lenses 300 constituting the projection optical system 1000 is spaced apart from the neighboring field lens 300 'constituting the adjacent projection optical system 1000' by a predetermined separation distance . At this time, in order to prevent a light source that has been output from one of the projection optical systems 1000 and passed through the screen 400 from being output from a neighboring projection optical system 1000 'and interfering with a light source that has passed through the screen 400 , An ultra-high-resolution table top display device 1 'having a plurality of projection optical systems 1000 can display an angle of a light source incident on the screen 400 using a field lens 300 at a predetermined angle, Or less. In this regard, Fig. 14 will be described together.

14 is a view showing neighboring field lenses 300 of FIG.

As described above, the field lens 300 constituting each projection optical system 1000 can be arranged to be spaced apart from the neighboring field lens 300 'by a predetermined separation distance?. At this time, letting the thickness of the screen 400 be t, the minimum angle can be calculated by the following equation.

Herein,? _Min is the minimum angle, t is the thickness of the screen 400, and? Is the separation distance between the neighboring field lenses 300.

Further, the maximum angle can be calculated by the following equation.

Where θ _max is the maximum angle, θ _d is the scattering angle of the screen 400, and θ _FOV is the viewing angle of the screen 400.

That is, in the super-multi-view tabletop display device 1 'according to the present invention, a wavenumber vector indicating a direction in which the light source passing through the telecentric lens group 200 advances toward the screen 400 is expressed by the above- A field lens 300 for changing the path of the light source to have an angle between the calculated minimum angle and the maximum angle may be provided. Accordingly, even if a light source is output from the plurality of video output apparatuses 100, the non-distorted three-dimensional image can be accumulated on the table 50. [

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by those skilled in the art that various changes and modifications may be made therein without departing from the spirit and scope of the invention as defined in the appended claims. It will be possible.

100: Video output device
200: Telecentric Lens Group
300, 300 ': field lens
400: Screen
500: micro lens array
1000, 1000 ': projection optical system

Claims (16)

A super high score table top display device for outputting an image in an integrated image manner through a screen provided on a top surface of a table on which an internal space is formed,
An image output device disposed on a bottom surface of the table and outputting a light source including image information in the screen direction;
A telecentric lens group which is provided between the screen and the video output device and is composed of a first lens having a positive refractive power and a second lens having a negative refractive power, ;
A field lens disposed between the telecentric lens group and the screen, the light source passing through the telecentric lens group being incident on the screen at a predetermined angle; And
And a microlens array arranged on the screen, the microlens array being composed of a hemispherical microlens unit through which a light source passing through the screen is incident,
Wherein a plurality of projection optical systems including the image output device, the telecentric lens, and the field lens are provided in the table, and a first field lens constituting one of the projection optical systems includes a second And is spaced apart from the field lens by a predetermined distance,
Wherein the predetermined angle is not smaller than a minimum angle calculated on the basis of the thickness of the screen and the spacing distance and is not larger than a maximum angle calculated on the basis of a scattering angle of the screen and a viewing angle of the screen. Top display device.
The method according to claim 1,
Wherein the first lens and the second lens are provided such that both surfaces of the first lens and the second lens have a meniscus shape convex in the screen direction.
3. The method of claim 2,
Wherein the first lens has a meniscus shape with a positive refractive power, a curvature radius of the lower surface is larger than a curvature radius of the upper surface,
Wherein the second lens has a curvature radius smaller than a curvature radius of an upper surface so as to have a meniscus shape with a negative refracting power.
The method of claim 3,
The radius of curvature of the lower surface of the first lens is 30.47 mm to 30.57 mm, the radius of curvature of the upper surface of the first lens is 16.94 mm to 16.99 mm,
Wherein a radius of curvature of the lower surface of the second lens is 16.514 mm to 16.574 mm, and a radius of curvature of the upper surface of the second lens is 23.451 mm to 23.551 mm.
The method according to claim 1,
Wherein the first lens and the second lens are in contact with each other so that the center of the upper surface of the first lens and the center of the lower surface of the second lens are spaced by a minute distance, aperture of the second lens is the same as the lens diameter of the lower surface of the second lens and the radius of curvature of the upper surface of the first lens is larger than the radius of curvature of the lower surface of the second lens.
The method according to claim 1,
Wherein the telecentric lens group corrects chromatic aberration by limiting a field size of a light source output from the image output device to a predetermined size or less.
The method according to claim 6,
Wherein the predetermined size is a length of the width of the field lens.
The method according to claim 1,
Wherein the screen includes an optical glass having a predetermined thickness and a film screen attached to an upper surface of the optical glass to scatter a light source passing through the optical glass,
The field lens includes:
And a convex shape in the direction of the video output device, the convex shape being provided on a lower surface of the optical glass.
delete delete delete The method according to claim 1,
Wherein the minimum angle is calculated through the following equation.

Here,? _Min is the minimum angle, t is the thickness of the screen, and? Is the separation distance.
The method according to claim 1,
Wherein the maximum angle is calculated by the following equation.

Where θ _max is the maximum angle, θ _d is the scattering angle of the screen, and θ _FOV is the viewing angle of the screen.
The method according to claim 1,
The micro lens unit includes:
Wherein the convex surface is convex in the screen direction, and the back surface is a plane aspherical surface lens.
15. The method of claim 14,
An optical mask having a blocking region and a transmissive region is attached to the back surface of each of the microlens units,
And wherein only a part of the light sources incident on the microlens unit by the optical mask toward the transmission region is output to the upper portion of the table.
The method according to claim 1,
Wherein an interval between the image output device and the telecentric lens group is 17.53 mm to 17.63 mm and an interval between the telecentric lens group and the field lens is 155.1 mm to 155.3 mm. Table top display device.

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