Image forming module and floating image creation device

Abstract

To provide an image forming module and a floating image creation device.SOLUTION: An image forming module is configured by comprising an image forming unit and a floating image creation unit. The floating image creation unit has an incident surface and an emission surface that are installed in parallel with one side of the image forming unit, have an optical axis, and are located on the opposite sides to each other. The incident surface is directed to the image forming unit, and receives an output light beam provided from the image forming unit to form a real image, which is formed on the outside of the emission surface. The absolute value of the curvature of radius of the image forming unit at a position where the incident surface approaches the optical axis, is smaller than the absolute value of the curvature of radius at a position where the emission surface approaches the optical axis. A floating image creation device comprises a light source and the image forming module. The floating image creation unit is installed in parallel with the other side of the image forming unit relative to the light source, and the image forming module creates a real image from a light beam emitted by the light source.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to an imaging module and a floating image generation device.

Background Art

[0002] With the progress of science and technology, display technologies have been continuously evolving, meeting the requirements for an improved visual experience demanded by consumers. Three-dimensional (3D) display technologies are classified into naked-eye type and glasses type. In the naked-eye type, no device needs to be worn, and an optical structure is installed in the display device. In the glasses type, devices such as polarizing lenses or filter plates are worn. The naked-eye 3D display technology has a good reputation among consumers due to its convenience and comfort, and among them, the floating projection technology has particularly attracted the attention of the public. Its feature is that the floating display device projects an image in space, enabling not only viewing of the floating image but also interaction at a short distance.

Summary of the Invention

Problems to be Solved by the Invention

[0003] Generally, in a floating display device, an imaging module projects an image in space. However, the viewing angle of a conventional imaging module is about 59°, that is, the projected image can only be observed within a range of 59° with respect to the optical axis of the imaging module. In other words, when the user's eyes are located outside the range of 59° with respect to the optical axis (usually overlapping with the central axis) of the imaging module in front of the floating display device, the projected image cannot be clearly seen. As described above, there is room for improvement in conventional imaging modules and floating display devices.

[0004] Therefore, the inventor of the present invention considered that the above-mentioned drawbacks could be improved, and as a result of intensive studies, arrived at the proposal of the present invention that reasonably and effectively improves the problems.

[0005] The present invention has been made in view of the above circumstances, and an example of the problem is to solve the above problems. That is, an object of the present invention is to provide an imaging module and a floating image with a wide viewing angle.

Means for Solving the Problems

[0006] In order to solve the above problems, the present invention employs the following means. The imaging module according to one aspect of the present invention includes an imaging unit and a floating image generation unit. The floating image generation unit is installed so as to be parallel to one side of the imaging unit, has an optical axis, and has an incident surface and an exit surface located on the opposite side. The incident surface is directed toward the imaging unit, and a real image is formed by the output light beam provided from the imaging unit and imaged outside the exit surface. The absolute value of the radius of curvature at the position where the incident surface approaches the optical axis is smaller than the absolute value of the radius of curvature at the position where the exit surface approaches the optical axis.

[0007] The floating image generation device according to the present invention includes a light source and an imaging module. The floating image generation unit is installed so as to be parallel to the other side of the imaging unit with respect to the light source, and the light beam emitted by the light source generates a real image by the imaging module.

Brief Description of the Drawings

[0008]

Fig. 1A

Fig. 1B

Fig. 2

Fig. 3

Fig. 4A

Fig. 4B

Fig. 4C

Embodiments for Carrying Out the Invention

[0009] Hereinafter, embodiments of the imaging module and the floating image generation device of the present invention will be described with reference to the drawings. However, the present invention is not limited to these embodiments, and the members, materials, etc. described below can be variously modified within the scope of the gist of the present invention.

[0010] In the accompanying drawings, for ease of understanding, the thicknesses of layers, films, panels, regions, etc. are enlarged. Throughout the specification, the same reference numerals in the same accompanying drawings indicate the same members. Incidentally, when a member of a layer, film, region, or substrate is "on" another member or "connected" to another member, it may be directly on the other member or directly connected to the other member, or an intermediate member may exist. Conversely, when a member is "directly on" another member or "directly connected" to another member, no intermediate member exists. As used herein, "connection" refers to physical and / or electrical connection. Also, "electrical connection" or "coupling" means that there is another member between two members.

[0011] In this specification, terms such as "first", "second", "third", etc. are only used to describe various members, elements, regions, layers, and / or parts in this specification, and these members, elements, regions, and / or parts are not limited by these terms. These terms are used to distinguish one member, element, region, layer, or part from another member, element, region, layer, or part. Therefore, the "first member", "element", "region", "layer", or "part" described below may also be a second member, element, region, layer, or part, without departing from the scope disclosed in this specification.

[0012] Also, the terms "lower" or "bottom" and "upper" or "top" are used herein to describe the relationship between one member and another as shown in the figures. It should be noted here that the terms include different orientations of the device other than the orientation shown in the figures. For example, when the device in the attached drawings is inverted, the member on the "lower" side of another member faces the "upper" side of the other member. Thus, the exemplary term "lower" includes the directions of "lower" and "upper", which are determined by the specific orientation of the attached drawings. Similarly, when the device is inverted in one of the attached drawings, the member "below" or "beneath" another member faces the "above" of the other member. Thus, the exemplary terms "lower surface" or "undersurface" include the directions of above and below.

[0013] As used herein, "about", "approximate", or "substantially" includes the value and the average value within an acceptable deviation range of a particular value that is definitive to an ordinary skilled person in the art, taking into account the particular quantity of measurement and errors associated with the measurement (i.e., the limitations of the measurement system). For example, "about" indicates within one or more standard deviations of the value, or within ±30%, ±20%, ±10%, ±5%. It should be noted that "about", "approximate", or "substantially" as used herein does not select an acceptable deviation range or standard deviation based on optical properties, etching properties, or other properties and apply one standard deviation to all properties.

[0014] As shown in the embodiments of FIGS. 1A and 1B, the imaging module 800 according to the present invention constitutes the floating image generating device 900 according to the present invention together with the light source 100. As shown in the embodiment of FIG. 1A, the floating image generating unit 300 is installed parallel to the other side of the imaging unit 200 with respect to the light source 100, and the light rays emitted by the light source 100 generate a real image that is a floating image by the imaging module 800. The floating image generating unit 300 is a single lens or a lens array, and the lens has a single-sided or double-sided convex lens structure and is manufactured using processes such as ultraviolet imprinting, injection molding, and hot pressing.

[0015] More specifically, as shown in the embodiment of FIG. 1B, the imaging module 800 displays a real-image floating image 510 on the other side of the floating image generation unit 300 with respect to the light source 100. A sensing module 700 is further combined with the floating image generation device 900 to form a floating image touch device 910. When the sensing module 700 senses that there is a touch operation within the sensing area 710, the floating image generation device 900 modifies the image.

[0016] As shown in the embodiment of FIG. 2, the imaging module 800 according to the present invention includes an imaging unit 200 and a floating image generation unit 300. The imaging unit 200 is provided with a pattern of the floating image to be formed. In this embodiment, the pattern in the imaging unit 200 has a blocking effect on light rays. For example, it has a fixed-pattern photograph, a negative film, or a photomask. In different embodiments, the imaging unit 200 may be a display panel such as a liquid crystal display panel, an organic light-emitting diode display panel, or a plasma display panel, or may be a light-emitting element such as a light-emitting diode. The floating image generation unit 300 is installed parallel to one side of the imaging unit 200. The imaging module 800 further includes a light amount aperture 400 installed between the imaging unit 200 and the floating image generation unit 300.

[0017] As shown in the embodiment of FIG. 2, the floating image generation unit 300 has an optical axis 301, and has an incident surface 310 and an exit surface 320 located on the opposite sides. The incident surface 310 faces the imaging unit 200, and a real image 500 is formed outside the exit surface 320 by the output light rays provided by the imaging unit 200. The absolute value of the radius of curvature at the position where the incident surface 310 approaches the optical axis 301 is smaller than the absolute value of the radius of curvature at the position where the exit surface 320 approaches the optical axis 301. In other words, the degree of curvature of the incident surface 310 is larger than that of the exit surface 320. Therefore, the real image 500 can still be visually observed by the eye 600 even when the viewing angle θ with respect to the optical axis 301 is ≧ 60° outside the exit surface 320. In this embodiment, the real image 500 can still be visually observed even when the viewing angle θ with respect to the optical axis 301 is 80° outside the exit surface 320. In other words, the viewing angle θ of the imaging module 800 according to the present invention reaches 80°, providing a preferable usage experience for the user.

[0018] More specifically, the incident surface 310 is represented by the following mathematical formula.

Equation

[0019] For example, as shown in the embodiment of FIG. 3, Z’ 310 is the sag of the floating image generation unit 300 in the direction of the optical axis 301 at the position 310’ of the incident surface 310, s’ 310 is the height from the optical axis 301 to the incident surface 310 at the position 310’ of the incident surface 310, C’310 is the reciprocal of the radius of curvature at the position 310’ of the incident surface 310. More specifically, the aspheric formula is generally expressed up to the 12th order. However, the higher the order, the greater the difficulty of processing. Therefore, when optimizing in the design or manufacturing process, for example, considering the aberration correction effect or manufacturing cost, the order required for optimization is determined, but it is not limited to selecting the 4th order coefficient for optimization. The exit surface 320 is expressed by the following formula.

Equation

[0020] The radius of curvature of the floating image generation unit 300 is affected by the material. Furthermore, the floating image generation unit 300 is a lens, and the relationship between the focal length of the lens and the refractive index of the lens is expressed by the following formula.

Equation

[0021] Simulation is performed using optical software (Zemax, USA). S 200 is the surface of the image displayed by the imaging unit 200 (see Figure 2), S 400 is the aperture stop 400, S 310 is the surface of the incident surface 310, S320 is the surface of the emission surface 320, S 500 is the real image 500. The interval distance refers to the linear distance on the optical axis 301 between two adjacent surfaces. For example, it is the interval distance of the surface S200, that is, the linear distance on the optical axis 301 from the surface S 200 to the surface S400. The simulation results are as follows. <Table 1: Example 1>

Table 1

[0022] <Table 2: Example 2>

Table 2

[0023] <Table 3: Comparative Example>

Table 3

[0024] As can be seen from the results in Table 1 to Table 3 above, the viewing angle θ of the comparative example where the radii of curvature on both sides of the imaging unit are the same is 60°. The absolute value of the radius of curvature at the position where the incident surface of the imaging module according to the present invention approaches the optical axis is smaller than the absolute value of the radius of curvature at the position where the emission surface approaches the optical axis, and its viewing angle θ is 80°, which is clearly excellent. Furthermore, as the viewing angle θ increases, the numerical value of the focal length decreases, and as the radius of curvature corresponding to S 310 (that is, the surface of the incident surface) decreases, the corresponding aspheric coefficient increases, and in this way, the light rays on the incident surface reach the emission surface. Also, as the refractive index decreases, the focusing ability decreases, and it is necessary to decrease the radius of curvature and increase the aspheric coefficient corresponding to S310 (that is, the surface of the incident surface).

[0025] On the one hand, the modulation transfer functions (MTFs) of Example 1, Example 2, and the comparative example are shown in FIGS. 4A, 4B, and 4C, respectively. Using the geometric MTF and a spatial frequency of 30 lp / mm, at 30 lp / mm in the chart, in the field of view of 0.7 on the optical axis and away from the axis, all the numerical values of the MTF are greater than 30%. In the field of view of 1.0, both Example 1 and Example 2 correspond to the conventional example, and in the field of view of 1.0, all are higher than the numerical values of the conventional MTF. As can be seen from this, at the viewing angle of 80° of Example 1 and Example 2, the optical quality corresponds to the conventional viewing angle of 59°.

[0026] The above-described embodiments are merely for explaining the technical idea and features of the present invention, and are intended to enable those skilled in the art to understand the content of the present invention and implement it accordingly, and do not limit the scope of the claims of the present invention. Therefore, improvements or modifications having various similar effects without departing from the spirit of the present invention shall be included in the following claims.

Explanation of Reference Numerals

[0027] 100 Light source 200 Imaging unit 300 Floating image generation unit 301 Optical axis 310 Incident surface 310’ position 320 Exit surface 400 Aperture 500 Real image 510 Floating image 600 Eye 700 Sensing module 710 Sensing area 800 Imaging module 900 Floating image generation device 910 Floating image touch device θ Field of view angle

Claims

1. An imaging unit, An imaging module, characterized in that it is provided parallel to one side of the imaging unit, has an optical axis, has an incident surface and an exit surface located on the opposite side, the incident surface is directed towards the imaging unit, a real image is formed by the output light rays provided by the imaging unit and is imaged outside the exit surface, and the absolute value of the radius of curvature at the position where the incident surface approaches the optical axis is smaller than the absolute value of the radius of curvature at the position where the exit surface approaches the optical axis, and a floating image generation unit.

2. The imaging module according to claim 1, characterized in that when the real image has a viewing angle with respect to the optical axis outside the exit surface of ≧ 60°, it is still visible to the naked eye.

3. The imaging module according to claim 2, characterized in that when the real image has a viewing angle with respect to the optical axis outside the exit surface of 80°, it is still visible to the naked eye.

4. The imaging module according to claim 1, characterized in that the incident surface is represented by the following mathematical formula. 【Number 4】 (where Z ｒ is the amount of deviation (sag) of the incident surface in the optical axis direction, C ｒ is the reciprocal of the absolute value of the radius of curvature at the position where the incident surface approaches the optical axis, s ｒ is the height from the optical axis to the incident surface, k is the conic coefficient, and k ≦ -2.65, and A4, A6, A8, A10, A12 are the aspheric coefficients of the 4th, 6th, 8th, 10th, and 12th orders, respectively.)

5. The imaging module according to claim 4, characterized in that -20 < k < -2.

65.

6. The imaging module according to claim 1, characterized in that the exit surface is represented by the following mathematical formula. 【Number 5】 (where Z ｅ is the amount of deviation (sag) of the exit surface in the optical axis direction, C ｅ is the reciprocal of the absolute value of the radius of curvature at the position where the exit surface approaches the optical axis, s ｅ is the height from the optical axis to the exit surface, k is the conic coefficient, and k < -1.5, and A4, A6, A8, A10, A12 are the aspheric coefficients of the 4th, 6th, 8th, 10th, and 12th orders, respectively.)

7. The imaging module according to claim 6, characterized in that -20 < k < -2.

65.

8. The imaging module according to claim 1, characterized in that the floating image generation unit is a lens, and the relationship between the focal length of the lens and the refractive index of the lens is represented by the following mathematical formula. 【Number 6】 (where f is the focal length of the lens, n is the refractive index, R １ is the radius of curvature of the incident surface, R ２ is the radius of curvature of the exit surface, and d is the thickness of the lens.)

9. A light source, A floating image generation device, characterized in that the floating image generation unit is installed parallel to the other side of the imaging unit with respect to the light source, and the light rays emitted by the light source form the output light rays by the imaging module to generate the real image, and the imaging module according to any one of claims 1 to 8.

Images