KR20160009835A - Optical Apparatus and Method for Shaping Line-Focused Parallel Light Beam - Google Patents

Optical Apparatus and Method for Shaping Line-Focused Parallel Light Beam Download PDF

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Publication number
KR20160009835A
KR20160009835A KR1020140090173A KR20140090173A KR20160009835A KR 20160009835 A KR20160009835 A KR 20160009835A KR 1020140090173 A KR1020140090173 A KR 1020140090173A KR 20140090173 A KR20140090173 A KR 20140090173A KR 20160009835 A KR20160009835 A KR 20160009835A
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KR
South Korea
Prior art keywords
light
mirrors
collimator
parallel
base
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KR1020140090173A
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Korean (ko)
Inventor
연용현
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주식회사 엠쏘텍
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Priority to KR1020140090173A priority Critical patent/KR20160009835A/en
Publication of KR20160009835A publication Critical patent/KR20160009835A/en

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    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B17/00—Systems with reflecting surfaces, with or without refracting elements
    • G02B17/006—Systems in which light light is reflected on a plurality of parallel surfaces, e.g. louvre mirrors, total internal reflection [TIR] lenses
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B26/00—Optical devices or arrangements for the control of light using movable or deformable optical elements
    • G02B26/08—Optical devices or arrangements for the control of light using movable or deformable optical elements for controlling the direction of light
    • G02B26/0816—Optical devices or arrangements for the control of light using movable or deformable optical elements for controlling the direction of light by means of one or more reflecting elements
    • G02B26/0825—Optical devices or arrangements for the control of light using movable or deformable optical elements for controlling the direction of light by means of one or more reflecting elements the reflecting element being a flexible sheet or membrane, e.g. for varying the focus
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B27/00—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00
    • G02B27/30—Collimators
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/0001—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems
    • G02B6/0011—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems the light guides being planar or of plate-like form
    • G02B6/0013—Means for improving the coupling-in of light from the light source into the light guide
    • G02B6/0023—Means for improving the coupling-in of light from the light source into the light guide provided by one optical element, or plurality thereof, placed between the light guide and the light source, or around the light source
    • G02B6/0031—Reflecting element, sheet or layer

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Length Measuring Devices By Optical Means (AREA)

Abstract

A parallel optical line beam generator capable of generating a wide parallel optical line beam as well as a simple structure and a narrow width, and thus applicable to various applications.
The parallel optical line beam generating apparatus of the present invention comprises: a mirror pair provided so as to face each other and composed of two mirrors that repeatedly reflect incident light and guide the incident light in a direction parallel to the reflection surface; And a collimator provided at a front end of one of the two mirrors and guided by the mirror pair so that the light beams emitted from the mirror pair are collimated in parallel. In a preferred embodiment, the parallel optical line beam generator further comprises a base of transparent material, wherein the two mirrors are installed on both sides of the base. In such a case, the two mirrors may be realized by a mirror coating layer provided on both sides of the base.
Even if the light incident from the light source is incident into the device with a very narrow beam width, a wide parallel light is emitted through the collimator. Accordingly, there is no need to separate the light source and the collimator from each other, the size of the device can be made very small, and it is advantageous in that the structure is very simple and can be manufactured at a low cost.

Description

Technical Field [0001] The present invention relates to an optical apparatus and a method for forming a parallel optical line beam,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical device, and more particularly, to an apparatus for controlling the traveling direction of light.

A parallel optical line beam refers to a light having a vertical cross section with respect to the traveling direction and having a narrow thickness, and the traveling direction of light is substantially the same at all points. A light source capable of projecting such a parallel optical line beam has been used in various fields. Examples of such a light source include a pattern or shape detecting device such as a video device, a two-dimensional or three-dimensional scanner, a three-dimensional printer, And the like.

Generally, the flared light line beam can be composed of a combination of a slit for narrowing the thickness of the light and a collimator for focusing the light. 1, the light 12 emitted from the light source 10 is converged by the collimator 20 and converted into the parallel light 22. A slit for blocking or blocking the undesired light may be provided between the light source 10 and the collimator 20 or at the rear end of the collimator 20.

However, there is a problem that the flare beam line generating device as shown in FIG. 1 may be too large in size depending on the application field. As a specific example, in an inspection apparatus for inspecting the thickness of a glass or cracks or flaws in a glass panel production process for an LCD display, the width of the glass panel may reach about 2 meters, and in such a device, A line beam that is equal to or greater than the width of the glass panel may be required. 1, the distance L between the light source 10 and the collimator 20 must be increased correspondingly to increase the width of the line beam, and the distance between the light source 10 and the collimator 20, The size of the device becomes correspondingly large. Accordingly, the illustrated apparatus requires a lot of installation space, and installation is difficult in a place where installation space is limited. If the distance L between the light source 10 and the collimator 20 is increased as described above, the light source 10 and the collimator 20 are very vulnerable to vibrations.

In this connection, in the prior art documents described below, Patent Document 1 and Patent Document 2 describe an apparatus for generating a parallel optical line beam by using a plurality of mirrors arranged in parallel to each other in parallel. Patent Document 3 describes an apparatus for generating a parallel optical line beam by combining a plurality of semi-transmissive mirrors and total reflection mirrors. However, the devices described in these documents are not only complicated in the structure of the apparatus, but also require a precise determination of the reflectance or transmittance of each mirror so that they are difficult to manufacture and the manufacturing cost is high.

Korean Patent Publication No. KR 10-2009-0018454 A (Samsung Electro-Mechanics Co., Ltd.) Feb. 20, 2009 Korean Registered Patent Publication No. KR 10-0863196 B1 (Samsung Electro-Mechanics Co., Ltd.) Oct. 7, 2008 Korean Registered Patent No. KR 10-0864017 B1 (Samsung Electro-Mechanics Co., Ltd.) Oct. 10, 2008

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems and provides a parallel optical line beam generator capable of generating a wide parallel optical line beam as well as a simple structure and a narrow width, To be a technical challenge.

It is another object of the present invention to provide a parallel optical line beam generating method that can be implemented by a simple structure apparatus and can generate a wide parallel optical line beam as well as a narrow width, Another technical problem is.

According to an aspect of the present invention, there is provided a parallel optical line beam generator comprising: a mirror pair including two mirrors arranged to face each other and guiding incident light in a direction parallel to the reflection surface while repeatedly reflecting light; And a collimator provided at a front end of one of the two mirrors and guided by the mirror pair so that the light beams emitted from the mirror pair are collimated in parallel.

In a preferred embodiment, the parallel optical line beam generator further comprises a base of transparent material, wherein the two mirrors are installed on both sides of the base. In such a case, the two mirrors may be realized by a mirror coating layer provided on both sides of the base.

It is preferable that a light input port for receiving the incident light is provided at a rear end of one of the two mirrors.

In one embodiment, the parallel optical line beam generator further includes a reflecting means for periodically changing the direction of the incident light between the light source and the light input port. Here, the light source and the reflecting means may be integrated with the two mirrors and the collimator.

According to another aspect of the present invention, there is provided a parallel optical line beam generating method comprising the steps of: inputting light through a pair of mirrors constituted by two mirrors provided so as to face each other; So as to be parallel to the two mirrors. The collimator provided at one end of the two mirrors converges the direction of light emitted from the mirror pair in parallel.

In one embodiment, the light is incident between the two mirrors while changing the direction of the light periodically according to time, so that scan light output at different emission points is output through the collimator with time.

According to the parallel optical line beam generating apparatus of the present invention, even when the light incident from the light source is incident into the base with a very narrow beam width, the parallel light of a wide width is emitted through the collimator. Accordingly, it is not necessary that the light source and the collimator are separated from each other, and the size of the device can be made very small.

The apparatus of the present invention is advantageous in that it can produce a wide parallel optical line beam as well as a narrow width, and the structure is very simple and can be manufactured at a low cost.

The parallel optical line beam generating apparatus of the present invention can be applied to a variety of applications, for example, a pattern or shape detecting device such as a video device, a two-dimensional or three-dimensional scanner, a three- Apparatus, and the like, and is particularly useful for inspection of large-sized workpieces.

1 is a schematic view for conceptually explaining a conventional parallel light generating method;
FIG. 2 is a perspective view of an embodiment of a parallel optical line beam generator according to the present invention; FIG.
3 is a view showing an example of a path of light propagation in a base;
Figure 4 shows the path of propagation of light propagating in different directions within the base;
5 is a view for explaining the operation in the imaging mode of the parallel optical line beam generating apparatus shown in FIG. 2; And
FIG. 6 is a view showing an operation of the parallel optical line beam generating apparatus shown in FIG. 2 in a scanning mode.

2, in a preferred embodiment of the present invention, a parallel optical line beam generator comprises a base 100 having a plate-like or columnar shape with an upper surface and a lower surface parallel to each other, And a collimator 150 provided at one end of the upper surface or the lower surface. The base 100 is preferably made of transparent glass so that light can be transmitted without loss inside the base 100. In a preferred embodiment, the collimator 150 is attached directly to one side end of the upper or lower surface of the base 100. [ However, in another embodiment, the collimator 150 may be spaced from one end of the upper surface or the lower surface of the base 100 while being supported by a separate support member. In the following description and claims, the side on which the collimator 150 is provided is referred to as "forward" and the opposite side is referred to as "rear" for convenience of explanation.

A first mirror 110 is installed on the upper surface of the base 100 so as to face the inside of the base and a second mirror 120 is installed on the lower surface of the base 100 so as to face the inside of the base. In a preferred embodiment, the first mirror 110 is implemented by performing a total reflection mirror coating on the upper surface. Likewise, the second mirror 120 is implemented by mirror coating the lower surface.

The base 100 may be provided with a light input port 112 for receiving light incident from a light source (not shown). In a preferred embodiment, the light input port 112 is provided on the upper surface of the base 100 or the rear end of the lower surface. However, in another embodiment, the light input port 112 may be provided on the rear side wall of the base 100. [ Although the light input port 112 is formed in a rectangular shape, the shape of the light input port 112 is not limited thereto, but may be a circular shape or other shapes. Similarly to the portion provided with the collimator 150, .

2, the collimator 150 is provided on the upper surface of the base 100, but may be provided on the lower surface of the base 100 in another embodiment. Although the light input port 112 is formed on the same surface as the collimator 150, that is, on the upper surface of the base 100, the light input port 112 is provided on the surface facing the collimator 150, . In other words, the terms 'upper surface' and 'lower surface' are used herein for reference purposes only and are not intended to limit the installation of the collimator 150 and the light inlet 112 on a specific surface.

The first mirror 110 and the second mirror 120 are installed to cover the entire upper surface or the lower surface of the base 100 except for the portion where the collimator 150 is installed and the light input port 112 . For example, in the embodiment in which the collimator 150 and the light input port 112 are provided on the upper surface of the base 100 as shown in FIG. 2, the first mirror 110 is arranged on the collimator And the second mirror 120 is installed to cover the entire lower surface of the base 100. The second mirror 120 is provided to cover the entire lower surface of the base 100. [ It is preferable that the four sides of the base 100 except for the upper surface and the lower surface are coated with a light absorbing paint or coated with nothing to prevent reflection of light from the side.

The parallel optical line beam generating apparatus of Fig. 2 operates as follows.

As shown in FIG. 3, the light from the light source 200 is incident through the light input port 112 in a state where a small inclination angle is given, that is, the light is inclined in the forward and backward direction in the vertical direction. The incident light travels downward and is totally reflected by the second mirror 120. The light totally reflected by the second mirror 120 travels upward and is totally reflected by the first mirror 110. This total internal reflection is repeatedly performed by the first and second mirrors 110 and 120 in the base 100. During the repetitive total reflection, the light advances in the horizontal direction due to the incidence angle at the time of incidence, so that the light travels in the zigzag within the base 100, and finally reaches the collimator 150, (Not shown). Here, 'horizontal direction' refers to a direction parallel to the plane on which the first and second mirrors 110 and 120 extend. The collimator 150 focuses the emitted light so that the traveling direction of the light emitted from each point becomes parallel so that parallel light is emitted.

4, light incident from the light source 200 to the light input port 112 travels inside the base 100 while maintaining a horizontal angle of incidence, and reaches the collimator 150 and is emitted. In Fig. 4, for convenience, only light beams propagating in both directions are illustrated, but they may propagate in a similar manner in all directions along the direction of the incident light. The light propagating in each direction is repeatedly reflected by the first and second mirrors 110 and 120 in the base 100 until it reaches the side wall of the collimator 150 or the base 100 And the light reaching the collimator 150 is finally converged by the collimator 150 and emitted as parallel light.

The parallel optical line beam generating apparatus of FIG. 2 has two modes according to an applied device, namely, an imaging mode in which parallel light is entirely emitted from a front surface of the collimator 150, And a scanning mode in which the output point is continuously changed in accordance with time. FIG. 5 shows a parallel light output operation in the imaging mode, and FIG. 6 shows a parallel light output operation in the scanning mode.

5, when the light incident from the light source 200 to the light input port 112 has a substantial spreading angle, the incident light is incident at a wide angle at substantially all azimuth angles. In the base 100, . Light traveling through the base 100 while being subjected to repetitive reflection is totally emitted through the collimator 150. At this time, the light emitted through the collimator 150 forms a cardboard shape when seen from the front or rear, and a line shape when viewed from above or below. Such imaging mode operation can be performed when the parallel optical line beam generating apparatus is combined with the image pickup apparatus and implemented in the form of a three-dimensional scanner, for example. Although the luminance of the emitted light may be different depending on the position of the collimator 150, the luminance level of each pixel is relatively less, for example, in the case of obtaining the outline of the object to be inspected, It can be used without problems in critical applications. Of course, the luminance difference at each point can be corrected by a separate luminance correction device.

In the scanning mode, it is preferable that the spreading angle of the incident light is substantially small so as to enhance the directivity of the parallel light to be emitted. In this case, it is preferable that a laser diode or other laser generating device having a small spread angle is used as the light source 200. In the scanning mode, incident light having a very high directivity is incident on the light input port 112 while changing its direction with time. For example, as shown in FIG. 6, the light to the light source 200 may be incident on the reflector 220 that is deflected in time, for example, by a reflection by a MEMS mirror or a galvanometer mirror, have.

In this case, the incident light propagates only in one direction within the base 100, and the collimator 150 emits light at only one point at an arbitrary moment. When the reflection device 220 rotates as time elapses, the point at which the light is emitted from the collimator 150 is continuously changed, so that output light for scanning the front of the collimator 150 can be emitted do. Even in such a case, the outgoing light looks like a shape as shown in FIG. 5 in the naked eye.

As shown in FIG. 5 or 6, according to the parallel optical line beam generating apparatus of the present invention, parallel light of a wide width is emitted through the collimator 150, while light incident from the light source 200 It may suffice to enter the inside of the base 100 with a very narrow beam width. Accordingly, the light source 200 and the collimator 150 need not be spaced apart from each other, and the size of the device can be made very small.

Particularly, in the application example shown in Fig. 6, since a wide-width scan light can be emitted, it becomes possible to photograph, recognize, or process an object over a wide range at high speed. For example, when the parallel optical line beam generating apparatus according to the present invention is applied to a large-sized three-dimensional scanner, it is not necessary to drive the stage by an actuator, and scanning can be performed at a high speed while the scanning object is fixed.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the invention.

For example, in the above description, the first mirror 110 and the second mirror 120 are implemented by the mirror coating formed on the upper and lower surfaces of the base 100. However, The base 100 may be omitted when the two mirrors 120 can be supported by separate rigid supporting members.

In the above embodiment, since light is emitted through the collimator 150 having a very small thickness, light emitted from the collimator 150 has a line beam shape, and parallel light is obtained by the converging function of the collimator 150. However, in order to further refine the shape of the line beam, the light generated from the light source may be further narrowed by a separate focusing device, or light may be incident into the device in the form of a line light.

The intensity of the light may be different according to the point of emission of the collimator 150 because the path traveled in the base 100 differs according to the point where the light is emitted from the collimator 150. [ As mentioned above, in the application example in which objects are simply identified, the difference in light intensity depending on the position may not be a problem. However, in an application example of performing fine image capturing such as a three-dimensional scanner, it is possible to offset the difference in intensity of light by correcting luminance and color level by a correction coefficient experimentally determined beforehand for each horizontal pixel by software.

On the other hand, as the light propagates through the repeated reflection in the base 100, the light path becomes longer, the beam width of the outgoing light becomes wider in the scanning mode, and the beam width becomes different depending on the position on the collimator 150 . In such a case, it is also possible to extract only the portion with the highest signal level from the detection signal obtained based on the scan light emitted as shown in FIG. 7, and perform necessary processing. For example, in an application example of positioning through three-dimensional scanning using scan light, a pixel having the highest signal level can be determined as an object or an edge thereof. Such signal processing is useful in applications related to three-dimensional scanners and position detection, and can be readily implemented by those skilled in the art based on the present specification, so that detailed description thereof will be omitted.

Therefore, it should be understood that the above-described embodiments are illustrative in all aspects and not restrictive. The scope of the present invention is defined by the appended claims rather than the detailed description and all changes or modifications derived from the meaning and scope of the claims and their equivalents are to be construed as being included within the scope of the present invention do.

100: Base
110: first mirror, 120: light input port
120: Second mirror
150: collimator
200: Light source
220: Reflector

Claims (8)

A mirror pair provided so as to face each other and composed of two mirrors which repeatedly reflect incident light and guide the incident light in a direction parallel to the reflection surface;
A collimator provided at a front end of one of the two mirrors and guided by the mirror pair so that the light rays emitted from the mirror pair are parallel to each other;
And the parallel optical line beam generator. The method according to claim 1,
A transparent base;
Respectively,
And the two mirrors are installed on both sides of the base. The method of claim 2,
Wherein the two mirrors are implemented by a mirror coating layer provided on both sides of the base. The method according to claim 2 or 3,
And a light input port for receiving the incident light is provided at a rear end of one of the two mirrors. The method of claim 4,
A reflecting means installed between the light source generating the light and the light inputting port and periodically changing the direction of the incident light according to time;
Further comprising: a parallel optical line beam generator for generating a parallel beam; The method of claim 5,
And the light source and the reflecting means are integrally formed. A step of causing light to be incident through a pair of mirrors constituted by two mirrors provided so as to face each other so that the incident light is progressed in a direction parallel to the two mirrors while being repeatedly reflected by the two mirrors; And
Parallelizing a direction of light emitted from the mirror pair by a collimator provided at one end of the two mirrors;
Wherein the parallel optical line beam generating method comprises the steps of: The method of claim 7,
Wherein the beam is periodically changed in accordance with time so that the light is incident between the two mirrors so that scan light having a different emission point is outputted over time through the collimator.
KR1020140090173A 2014-07-17 2014-07-17 Optical Apparatus and Method for Shaping Line-Focused Parallel Light Beam KR20160009835A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20230140644A (en) 2022-03-29 2023-10-10 중앙대학교 산학협력단 Design of a Quasi-Direct Drive Actuator with Embedded Pulley for a Compact, Lightweight, and High-Bandwidth Exosuit

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100863196B1 (en) 2007-06-28 2008-10-13 삼성전기주식회사 Line beam generator
KR100864017B1 (en) 2007-06-28 2008-10-16 삼성전기주식회사 Line beam generator
KR20090018454A (en) 2007-08-17 2009-02-20 삼성전기주식회사 Line beam generator and manufacturing process of the same

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100863196B1 (en) 2007-06-28 2008-10-13 삼성전기주식회사 Line beam generator
KR100864017B1 (en) 2007-06-28 2008-10-16 삼성전기주식회사 Line beam generator
KR20090018454A (en) 2007-08-17 2009-02-20 삼성전기주식회사 Line beam generator and manufacturing process of the same

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20230140644A (en) 2022-03-29 2023-10-10 중앙대학교 산학협력단 Design of a Quasi-Direct Drive Actuator with Embedded Pulley for a Compact, Lightweight, and High-Bandwidth Exosuit

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