WO2019088453A1

WO2019088453A1 - Diffuser for laser projector

Info

Publication number: WO2019088453A1
Application number: PCT/KR2018/011514
Authority: WO
Inventors: 서종식; 정상원; 김민기
Original assignee: (주)알비케이이엠디
Priority date: 2017-11-03
Filing date: 2018-09-28
Publication date: 2019-05-09

Abstract

The present invention relates to a diffuser for a laser projector and, more specifically, to a diffuser for a laser projector, which reduces speckle noise generated in an image projected from a projector using a laser light source. The diffuser for the laser projector of the present invention comprises: a glass through which a laser beam passes; a base for supporting the glass such that the glass can vibrate in the direction perpendicular to the direction in which the laser beam travels; and a coil and a magnet, which are mounted in the base and generate electromagnetic force such that the glass vibrates, wherein the base includes a coupling unit to which the glass is coupled, a fixing unit in which one of the coil and the magnet, which face each other, is mounted, and a vibration support plate, which connects the coupling unit with the fixing unit, and resonates when the coupling unit vibrates together with the glass by means of the electromagnetic force.

Description

Diffuser for laser projector

The present invention relates to a diffuser for a laser projector, and more particularly, to a diffuser for a laser projector for reducing speckle noise generated in an image projected from a projector using a laser light source.

In recent years, projection display devices using a laser as a light source have been widely used. The projection display device is advantageous in that it can implement a very large-sized image to a very small-sized image, which is difficult to be realized by a display language such as a general LCD or PDP.

However, such a projection display device has the disadvantage that the quality of an image is degraded as compared with other display devices that emit light directly on the screen, because the projection display device implements the image by scanning the screen with the light modulated by the laser light source.

This is because a speckle noise or a speckle pattern is generated in an image when using a laser projection display device. To suppress such speckle noise, various methods are applied. Among them, there is a method of suppressing the speckle noise by shaking the diffuser.

1 is a diagram schematically showing a configuration of a projector apparatus using a conventional laser light source. A conventional projector apparatus using a laser light source includes a laser light source, a dichroic mirror, a reflector, a diffuser, a beam shaper, a field glass, an optical modulator, a projection glass, and a polarizing beam splitter.

On the other hand, in order to develop a portable small projector or to use a projector of a size enough to be embedded in a notebook or the like, it is necessary to develop a projector having a small size and low power consumption.

Korean Patent Publication No. 10-1583113 (Jan. 19, 2016) and Korean Patent Registration No. 10-1248174 (Apr. 31, 2013) disclose a conventional laser projector.

SUMMARY OF THE INVENTION The present invention provides a diffuser for a laser projector capable of reducing a speckle noise generated in an image projected from a projector by vibrating a glass transmitted through a laser beam emitted from a laser light source, There is a purpose.

In order to achieve the above object, a diffuser for a laser projector according to the present invention comprises: a glass through which laser light is transmitted; A base for supporting the glass so that the glass can vibrate in a direction perpendicular to the direction in which the laser light travels; And a magnet and a coil mounted on the base to generate an electromagnetic force to vibrate the glass. The base includes a coupling portion to which the glass is coupled, a fixing portion to which the coil and the magnet facing each other are mounted, And a vibration supporting plate which connects the coupling unit and the fixing unit and resonates when the coupling unit vibrates together with the glass by the electromagnetic force.

The fixing part includes a fixing plate integrally formed with the vibration supporting plate and a cover coupled with the fixing plate. The coil is mounted on the cover, and the magnet is mounted on the coupling part and faces the coil.

The coupling portion, the fixing plate, and the vibration supporting plate are integrally formed using a metal plate, and the vibration supporting plate is formed by bending a metal plate.

The two coils are mounted side by side on the cover, and the magnet facing the two coils is divided into three parts according to polarities, and the center part of the magnet divided into three parts has two The polarity of the center portion being different from the polarity of the remaining portion located on both sides of the center portion, and the directions of the currents flowing in the two coils are opposite to each other.

In addition, a curved stress relief groove is formed in the vibration supporting plate to prevent stress from concentrating on a part of the glass when the glass vibrates.

According to another aspect of the present invention, there is provided a diffuser for a laser projector, comprising: a first glass through which laser light is transmitted; A first support for supporting the first glass; A first driving unit for generating an electromagnetic force such that the first glass vibrates perpendicularly to a direction in which the laser beam travels; A second glass disposed side by side with the first glass and through which the laser light is transmitted; A second support for supporting the second glass; A second driving unit for generating an electromagnetic force such that the second glass vibrates perpendicularly to a direction in which the laser beam travels; And a base to which the first supporting part and the second supporting part are fixedly mounted, wherein the laser light sequentially transmits the first glass and the second glass, and the first glass and the second glass oscillate in directions perpendicular to each other do.

The first glass and the second glass are vibrated with a phase difference of 90 degrees and the laser light passing through the first glass and the second glass sequentially is refracted along the vibration direction of the first glass and the second glass, Shake occurs in the form.

The first driving unit may include two first coils fixedly mounted on the first supporting unit and a first magnet vibrating together with the first glass so as to face the two first coils, The driving unit includes two second coils fixedly mounted on the second support unit and a second magnet positioned to face the two second coils and vibrated together with the second glass.

The first supporting part includes a first engaging part to which the first glass and the first magnet are coupled, a first fixing part to which the first coil is mounted, and a second fixing part to connect the first engaging part and the first fixing part And a first vibration supporting plate resonating when the first coupling part oscillates together with the first glass by an electromagnetic force, the second supporting part includes a second coupling part in which the second glass and the second magnet are coupled, And a second vibration supporting plate that connects the second coupling unit and the second fixing unit and resonates when the second coupling unit vibrates together with the second glass by electromagnetic force, .

And the base is composed of a first base and a second base perpendicular to each other, the first support being mounted on the first base and positioned in parallel with the second base, and the second support being mounted on the second base And the first glass and the second glass are positioned to face each other.

The diffuser for a laser projector according to the present invention can reduce the speckle noise generated in the image projected from the projector by vibrating the glass transmitted through the laser light emitted from the laser light source and realize a simple structure and effective oscillation with a small force To a diffuser for a laser projector.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a view schematically showing a configuration of a conventional projector apparatus using a laser light source. Fig.

2 is a perspective view of a diffuser for a laser projector according to a first embodiment of the present invention;

3 is an exploded perspective view of a diffuser for a laser projector according to a first embodiment of the present invention.

4 is a side view of a diffuser for a laser projector according to a first embodiment of the present invention;

5 is a sectional view taken along the line A-A of Fig.

6 is a perspective view showing a coil and a magnet according to a first embodiment of the present invention.

7 is an operational state view of a diffuser for a laser projector according to the first embodiment of the present invention.

8 is a perspective view of a diffuser for a laser projector according to a second embodiment of the present invention;

9 is an exploded perspective view of a diffuser for a laser projector except for the second support portion of the present invention.

10 is an exploded perspective view of a diffuser for a laser projector except for the first support part of the present invention;

11 is a perspective view showing a first coil and a first magnet separately according to a second embodiment of the present invention.

12 is a view showing a first glass and a second glass separately according to a second embodiment of the present invention;

13 is a view showing a movement path of laser light transmitted through the first glass and the second glass as the first glass and the second glass vibrate according to the second embodiment of the present invention.

The present invention relates to a diffuser for a laser projector which vibrates a glass through which laser light emitted from a laser light source is transmitted in order to reduce speckle noise generated in an image projected from a projector using the laser light source.

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

First Embodiment

The diffuser for a laser projector according to the first embodiment of the present invention comprises a glass 100, a base 200, a coil 300 and a magnet 400, as shown in Figs.

The glass 100 is located on the path along which the laser beam travels, and the laser beam emitted from the laser light source is transmitted. As the glass 100 vibrates finely, the laser light passing through the glass 100 is refracted and shaken finely in accordance with the vibration of the glass 100.

As shown in FIG. 2, the base 200 supports the glass 100 so that the glass 100 can vibrate in a direction perpendicular to the direction in which the laser light advances. In addition, the coil 300 and the magnet 400 are mounted on the base 200 so as to face each other.

3, the base 200 includes a coupling portion 210, a fixing portion 220, and a vibration supporting plate 230. [

A through hole 211 is formed in the coupling part 210 and the glass 100 is coupled. A mounting portion 212 is formed in the coupling portion 210 to mount the magnet 400 in a direction toward the fixing portion 220.

The coil 300 is mounted on the fixing portion 220. More specifically, the fixing unit 220 includes a fixing plate 221 and a cover 222. The cover 222 is coupled to the fixing plate 221 and protrudes in a direction toward the coupling portion 210, and the coil 300 is mounted.

The vibration supporting plate 230 connects the coupling part 210 and the fixing part 220. Specifically, the vibration supporting plate 230 is formed integrally with the coupling portion 210 and the fixing plate 221. The vibration supporting plate 230 resonates when the coupling part 210 vibrates together with the glass 100 by the electromagnetic force. As shown in FIG. 4, a curve-shaped stress reducing groove 231 is formed in the vibration supporting plate 230 to prevent stress from concentrating on a part of the vibration supporting plate 230 when the glass 100 vibrates.

The coupling portion 210, the fixing plate 221, and the vibration supporting plate 230 are integrally formed using a metal plate, and the vibration supporting plate 230 is formed by bending a metal plate.

5 and 6, the coil 300 and the magnet 400 are mounted on the base 200 to generate an electromagnetic force so that the glass 100 vibrates.

Two coils 300 are mounted side by side on the cover 222. The directions of the currents flowing through the two coils 300 are opposite to each other. That is, a current flows in a counterclockwise direction to one of the coils 300 of the two coils 300, and a current flows in a clockwise direction to the other one of the coils 300.

The magnet 400 is attached to the coupling part 210 and faces the coil 300. The magnet 400 is mounted on the mounting portion 212 formed on the coupling portion 210 and faces the coil 300 as described above. Specifically, the magnet (400) facing the two coils (300) is divided into three parts according to the polarity of the surface facing the coil (300). The central portion of the three portions of the magnet 400 faces the two coils 300 at the same time. And the remaining two parts located on both sides of the center have polarity different from that of the central part.

According to various embodiments of the present invention, the diffuser for a laser projector of the present invention may include one coil 300 and one magnet 400 having two poles facing the coil 300.

The diffuser for a laser projector according to the present invention as described above is installed inside a laser projector so that laser light is transmitted through the glass 100. At this time, the electromagnetic waves generated by the coil 300 and the magnet 400 cause the glass 100 coupled to the coupling part 210 and the coupling part 210 to vibrate. That is, when an electromagnetic force is generated between the coil 300 and the magnet 400, the coil 300 is fixed to the fixed portion 220 and the magnet 400 is vibrated to the left and right by the electromagnetic force. 7, the coupling part 210 and the glass 100 are vibrated and the coupling part 210 is integrally formed with the coupling part 210 as the coupling part 210 is vibrated, The oscillation supporting plate 230 supporting the coupling part 210 resonates, so that the vibration intensity and the amplitude can be increased with a small force. Further, the vibration of the glass 100 through which laser light is transmitted can effectively reduce the speckle noise generated in the image projected from the projector.

Second Embodiment

8 to 13, the diffuser for a laser projector according to the second embodiment of the present invention includes a base 1100, a first support part 1200a, a first glass part 1300a, a first drive part 1410a, A second support part 1200b, a second glass part 1300b, and a

second driving part

1410b and 1420b.

As shown in FIGS. 8 to 10, the first support part 1200a and the second support part 1200b are fixedly mounted to the base 1100. As shown in FIG. Specifically, the base 1100 includes a first base 1110 and a second base 1120 which are perpendicular to each other. In other words, the base 1100 is bent in the " a " shape so that the first support part 1200a is mounted at one end and the second support part 1200b is mounted at the other end. The first support part 1200a and the second support part 1200b are mounted on different surfaces with respect to the base 1100.

The first supporting part 1200a supports the first glass 1300a so that the first glass 1300a can vibrate in a direction perpendicular to the direction in which the laser light advances. The first support portion 1200a is mounted on the first base 1110 and is disposed side by side with the second base 1120.

Specifically, as shown in FIG. 9, the first supporting portion 1200a includes a first engaging portion 1210a, a first fixing portion 1220a, and a first vibration supporting plate 1230a.

A first through hole 1211a is formed in the first coupling portion 1210a and a first glass 1300a is coupled. The first coupling portion 1210a is formed with a first mounting portion 1212a on which the first magnet 1420a is mounted in a direction toward the first fixing portion 1220a.

A first coil 1410a is mounted on the first fixing portion 1220a. The first fixing part 1220a includes a first fixing plate 1221a and a first cover 1222a. The first cover 1222a is coupled to the first fixing plate 1221a and protrudes in a direction toward the first coupling portion 1210a, and a first coil 1410a is mounted.

The first vibration supporting plate 1230a connects the first coupling portion 1210a and the first fixing portion 1220a. Specifically, the first vibration supporting plate 1230a is integrally formed with the first coupling portion 1210a and the first fixing plate 1221a. The first vibration supporting plate 1230a resonates when the first coupling part 1210a vibrates together with the first glass 1300a by electromagnetic force. The first vibration supporting plate 1230a is formed with a curved stress relief groove H to prevent stress from concentrating on a portion of the first glass 1300a when the first glass 1300a vibrates.

The first coupling portion 1210a, the first fixing plate 1221a, and the first vibration supporting plate 1230a are integrally formed using a metal plate, and the first vibration supporting plate 1230a is formed by bending a metal plate do.

The first glass 1300a is located on the path along which the laser light travels and the laser light emitted from the laser light source is transmitted. As the first glass 1300a vibrates finely, the laser light passing through the first glass 1300a is also slightly refracted and shaken due to the vibration of the first glass 1300a.

The first driving unit generates an electromagnetic force such that the first glass 1300a oscillates perpendicularly to the direction in which the laser light advances. The first driving part includes two first coils 1410a fixed to the first supporting part 1200a and a first magnet 1410a positioned to face the two first coils 1410a and vibrating together with the first glass 1300a. (1420a).

Two first coils 1410a are mounted side by side on the first cover 1222a. The directions of the currents flowing through the two first coils 1410a are opposite to each other. That is, as shown in FIG. 11, a current flows in a counterclockwise direction in one of the two first coils 1410a and a current flows in a clockwise direction in the other one of the first coils 1410a.

The first magnet 1420a is mounted on the first coupling portion 1210a and faces the first coil 1410a. The first magnet 1420a is mounted on the first mounting portion 1212a formed on the first engaging portion 1210a and faces the first coil 1410a. Specifically, the first magnet 1420a facing the two first coils 1410a is divided into three portions according to the polarity of the surface facing the first coil 1410a. The central portion of the three portions of the first magnet 1420a faces the two first coils 1410a at the same time. The other two portions located on both sides of the central portion of the first magnet 1420a have a polarity different from that of the central portion.

Meanwhile, according to various embodiments of the present invention, the first driving unit may include one first coil 1410a and one first magnet 1420a whose surfaces facing the first coil 1410a are divided into two poles .

The second support part 1200b supports the second glass 1300b so that the second glass 1300b can vibrate in a direction perpendicular to the direction in which the laser light advances. The second support portion 1200b is mounted on the second base 1120 and is located side by side with the first base 1110. [

Specifically, as shown in FIG. 10, the second support portion 1200b includes a second engagement portion 1210b, a second fixing portion 1220b, and a second vibration support plate 1230b.

A second through hole 1211b is formed in the second coupling portion 1210b, and a second glass 1300b is coupled. The second engaging portion 1210b is formed with a second mounting portion 1212b on which the second magnet 1420b is mounted in a direction toward the second fixing portion 1220b.

A second coil 1410b is mounted on the second fixing portion 1220b. The second fixing part 1220b includes a second fixing plate 1221b and a second cover 1222b. The second cover 1222b is coupled to the second fixing plate 1221b and protrudes in a direction toward the second coupling portion 1210b, and a second coil 1410b is mounted.

The second vibration supporting plate 1230b connects the second coupling portion 1210b and the second fixing portion 1220b. Specifically, the second vibration supporting plate 1230b is integrally formed with the second engaging portion 1210b and the second fixing plate 1221b. The second vibration supporting plate 1230b resonates when the second coupling portion 1210b vibrates together with the second glass 1300b by the electromagnetic force. The second vibration supporting plate 1230b is formed with a curved stress relief groove H in order to prevent stress from concentrating on a part of the second glass 1300b when the second glass 1300b vibrates.

The second vibration plate 1221b and the second vibration plate 1230b are integrally formed by using a metal plate and the second vibration plate 1230b is formed by bending a metal plate do.

The second glass 1300b is located on the path along which the laser beam travels, and the laser beam emitted from the laser light source is transmitted. The second glass 1300b vibrates finely as in the first glass 1300a described above and the laser light passing through the second glass 1300b is also slightly refracted and shaken according to the vibration of the second glass 1300b . Then, the laser light sequentially passes through the first glass 1300a and the second glass 1300b, and the first glass 1300a and the second glass 1300b vibrate in directions perpendicular to each other.

The second driving unit generates an electromagnetic force such that the second glass 1300b oscillates perpendicularly to the direction in which the laser light advances. The second driving part includes two second coils 1410b fixed to the second supporting part 1200b and a second magnet 1410b positioned to face the two second coils 1410b and vibrating together with the second glass 1300b. (1420b).

Two of the second coils 1410b are mounted side by side on the second cover 1222b. The directions of the currents flowing in the two second coils 1410b are opposite to each other. That is, a current flows in a counterclockwise direction to any one of the two second coils 1410b, and a current flows in a clockwise direction to the other one of the second coils 1410b.

The second magnet 1420b is mounted on the second engaging portion 1210b and faces the second coil 1410b. The second magnet 1420b is mounted on the second mounting portion 1212b formed on the second engaging portion 1210b and faces the second coil 1410b. Specifically, the second magnet 1420b facing the two second coils 1410b is divided into three parts according to the polarity of the surface facing the second coil 1410b. The central portion of the three portions of the second magnet 1420b faces the two second coils 1410b at the same time. The remaining two portions located on both sides of the central portion of the second magnet 1420b have polarities different from those of the central portion.

According to various embodiments of the present invention, the second driving unit may include one second coil 1410b and one second magnet 1420b having two poles facing the second coil 1410b .

The diffuser for a laser projector according to the present invention having the above-described structure is installed inside a laser projector so that laser light sequentially passes through the first glass 1300a and the second glass 1300b.

At this time, due to the electromagnetic force generated by the first coil 1410a and the first magnet 1420a, the first glass 1300a coupled to the first coupling portion 1210a and the first coupling portion 1210a vibrates do. When an electromagnetic force is generated between the first coil 1410a and the first magnet 1420a, the first coil 1410a is fixed to the first fixing portion 1220a and the first magnet 1420a is fixed to the electromagnetic force Thereby vibrating left and right. As the first coupling portion 1210a and the first glass 1300a are vibrated and the first coupling portion 1210a vibrates, the first coupling portion 1210a and the first coupling portion 1210a are formed integrally with the first coupling portion 1210a, The first vibration supporting plate 1230a supporting the first coupling portion 1210a is resonated so that the vibration intensity and the amplitude can be increased with a small force.

The electromagnetic force generated by the second coil 1410b and the second magnet 1420b causes the second glass 1300b coupled to the second coupling portion 1210b and the second coupling portion 1210b to vibrate do. When the electromagnetic force is generated between the second coil 1410b and the second magnet 1420b, the second coil 1410b is mounted and fixed to the second fixing portion 1220b, and the second magnet 1420b is fixed to the electromagnetic force Thereby vibrating left and right. The second coupling portion 1210b and the second glass 1300b are vibrated and the second coupling portion 1210b is oscillated to be integrally formed with the second coupling portion 1210b so that the second coupling portion 1210b The second vibration supporting plate 1230b supporting the second coupling portion 1210b is resonated so that the vibration intensity and the amplitude can be increased with a small force.

The first glass 1300a and the second glass 1300b oscillate in a direction perpendicular to each other with a phase difference of 90 degrees and are transmitted through the first glass 1300a and the second glass 1300b, Is refracted along the vibration directions of the first glass 1300a and the second glass 1300b, and shaking occurs in the form of a closed curve. That is, as shown in FIGS. 12 and 13, the first glass 1300a and the second glass 1300b oscillate in a direction perpendicular to each other by a phase difference of 90 degrees so that the first glass 1300a and the second glass 1300b The laser light transmitted in turn has a circular or rectangular shake. Accordingly, the speckle noise generated in the image projected from the projector can be effectively reduced.

Claims

A glass through which laser light is transmitted;

A base for supporting the glass so that the glass can vibrate in a direction perpendicular to the direction in which the laser light travels;

And a coil and a magnet mounted on the base to generate an electromagnetic force to vibrate the glass,

The base includes:

A coupling portion to which the glass is coupled,

A fixed portion on which one of the coils and the magnet facing each other is mounted,

And a vibration supporting plate connecting the coupling portion and the fixing portion and resonating when the coupling portion vibrates together with the glass by the electromagnetic force.
The method according to claim 1,

Wherein the fixing portion comprises a fixing plate integrally formed with the vibration supporting plate and a cover engaged with the fixing plate,

The coil is mounted on the cover,

And the magnet is mounted on the coupling portion to face the coil.
The method of claim 2,

The coupling portion, the fixing plate, and the vibration supporting plate are integrally formed using a metal plate,

Wherein the vibration supporting plate is formed by bending a metal plate.
The method of claim 2,

Two coils are mounted side by side on the cover,

The magnet facing the two coils is divided into three parts according to the polarity of the surface facing the coil,

The center portion of the magnet divided into three portions faces the two coils at the same time and the polarity of the center portion is different from the polarity of the remaining portions located on both sides of the center portion,

And the directions of the currents flowing through the two coils are opposite to each other.
The method according to claim 1,

Wherein the vibration supporting plate is formed with a curved stress reducing groove to prevent stress from concentrating on a part of the glass when the glass vibrates.
A first glass through which laser light is transmitted;

A first support for supporting the first glass;

A first driving unit for generating an electromagnetic force such that the first glass vibrates perpendicularly to a direction in which the laser beam travels;

A second glass disposed side by side with the first glass and through which the laser light is transmitted;

A second support for supporting the second glass;

A second driving unit for generating an electromagnetic force such that the second glass vibrates perpendicularly to a direction in which the laser beam travels; And

And a base to which the first support portion and the second support portion are fixedly mounted,

Wherein the laser light passes through the first glass and the second glass in turn,

Wherein the first glass and the second glass oscillate in directions perpendicular to each other.
The method of claim 6,

The first glass and the second glass are vibrated with a phase difference of 90 degrees and the laser light passing through the first glass and the second glass in order is refracted along the vibration direction of the first glass and the second glass, And a shake occurs in the laser projector.
The method of claim 6,

The first driving unit may include two first coils fixedly mounted on the first supporting unit and a first magnet vibrating together with the first glass so as to face the two first coils,

Wherein the second driving part comprises two second coils fixedly mounted on the second supporting part and a second magnet positioned to face the two second coils and vibrated together with the second glass. Diffuser for projector.
The method of claim 8,

The first support portion

A first coupling unit for coupling the first glass and the first magnet,

A first fixing part on which the first coil is mounted,

And a first vibration supporting plate connecting the first coupling portion and the first fixing portion and resonating when the first coupling portion vibrates together with the first glass by an electromagnetic force,

The second support portion

A second engaging portion to which the second glass and the second magnet are coupled,

A second fixing part on which the second coil is mounted,

And a second vibration supporting plate connecting the second coupling portion and the second fixing portion and resonating when the second coupling portion vibrates together with the second glass by an electromagnetic force.
The method of claim 6,

The base includes a first base and a second base perpendicular to each other,

Wherein the first support portion is mounted on the first base and positioned in parallel with the second base,

The second support portion being mounted on the second base and positioned in parallel with the first base,

Wherein the first glass and the second glass are positioned to face each other.