KR100833863B1 - Contrast ratio adjustment unit and projection apparatus using the same - Google Patents

Abstract

A contrast ratio adjustment unit and a projector with the same are provided to simplify assembly and complexity of an electromagnet by forming a core protector in one body with the electromagnet. A contrast ratio adjustment unit includes a frame(132), blades(141,142), and driving units(145,148). The frame has a through hole for an image beam. The blades are formed on the frame and control the open area of the through hole. The driving units rotate the blades and include permanent magnets(146,149) and electromagnets(147,150). The permanent magnets are fixed on the lower part of the blade. The electromagnets are positioned opposite to each other beside both poles of the permanent magnets and include cores(147a,150a), a core protector preventing electrification of the core, and coils(147b,150b) surrounding the core protector.

Description

Contrast ratio adjustment unit and projection apparatus using the same

1 is a schematic diagram showing an embodiment of a projection apparatus using a contrast ratio adjustment unit according to the present invention.

2 is a cross-sectional view taken along the line II of FIG. 1 as an embodiment of the contrast ratio adjusting unit according to the present invention.

3 is a schematic diagram showing an embodiment of a drive unit used in the contrast ratio adjustment unit according to the present invention.

4 is a schematic view showing another embodiment of a drive unit used in the contrast ratio adjustment unit according to the present invention.

<Explanation of symbols for the main parts of the drawings>

146, 149: permanent magnet 147, 150: electromagnet

147a, 150a: core 147b, 150b: coil

151: core protector 151a: first plate

151b: second plate 151c: body part

The present invention relates to a contrast ratio adjustment unit and a projection device using the same, and more particularly, to a driving unit of a light blocking structure for contrast adjustment.

Recently, projection devices using micro devices are becoming smaller and lighter, as well as larger screens, and their purpose is A / V (Audio / Video) for high-definition video in the office. Its use is also expanding. In the case of A / V use, the contrast of the image occurs continuously and at a high frequency, unlike in office use, and the difference in contrast is further shown to be an important factor in improving image quality. Therefore, in the case of a projection device using a micro device, the importance of improving the contrast ratio is increasing in addition to factors such as brightness, which is important in existing offices. Accordingly, it is required to apply the device for enhancing the contrast ratio, which can improve the contrast ratio, to increase the light transmission area more efficiently, and to provide a light blocking structure that accurately controls the rotation angle.

The present invention has been made in an effort to provide a contrast ratio control unit and a projection device using the same, capable of precisely adjusting the rotation angle of the light blocking structure for increasing the contrast ratio.

In order to achieve the above object, the contrast ratio adjustment unit of the projection apparatus according to the present invention is provided with a frame having an image light passing hole, and provided on the frame, at least one blade for adjusting the open area of the image light passing hole and the blade It includes a drive unit for rotating the drive, the drive unit is composed of a permanent magnet fixed to the lower portion of the blade, and an electromagnet disposed to face each of the anode of the permanent magnet, the electromagnet is the core, the core It is preferable to include a coil surrounding the core protector and the core protector to prevent the energization of the blade, the rotation angle of the blade.

In addition, in order to achieve the above object, the projection apparatus using the contrast ratio adjustment unit according to the present invention is an illumination system for aligning the light emitted from the lamp to emit light having any one polarization component, and reflects the light incident from the illumination system At least one lens is mounted inside a barrel including a frame including an image light passing system and a frame in which the image light passing hole is formed, thereby projecting light generated by the image light forming system onto a screen. A projection system, provided on the frame, at least one blade for adjusting the open area of the image light passing hole, and a driving unit for rotating the blade, wherein the driving unit is fixed to the lower portion of the blade. Permanent magnets and electromagnets disposed to face the anodes of the permanent magnets, Seating the core and, to prevent energization of the core, preferably comprises a core portion and a protective coil enclosing the core protection unit for determining a rotation angle of the blade.

Hereinafter, with reference to the accompanying drawings embodiments of the contrast ratio adjustment unit and a projection apparatus using the same will be described as follows. At this time, the configuration and operation of the present invention shown in the drawings and described by it will be described as at least one embodiment, by which the technical spirit of the present invention and its core configuration and operation is not limited.

1 is a schematic view showing an embodiment of a projection apparatus using a contrast ratio adjustment unit according to the present invention, comprising an illumination system 110, an image light forming system 120, a projection system 130 and a contrast ratio adjustment unit 140 do.

The illumination system 110 is to emit light having any one polarization component to the image light forming system 120 by aligning the light irradiated from the lamp 100. An integrator and a polarized beam splitter PBS 112, a color wheel 114, a plurality of illumination lenses 116, and a block-type PBS.

The integrator and the PBS 112 uniformize the light emitted from the lamp 100 to be uniformly distributed, and align the light having one polarization component. In the present invention, the integrator may use various beam shapers such as a light tunnel or a light rod.

The color wheel 114 separates the light emitted from the integrator and the PBS into red or green or blue light.

The plurality of illumination lenses 116 focus light separated from the color wheel 114 to the block-type PBS 118.

The block type PBS 118 reflects the light passing through the plurality of illumination lenses 116 to the image light forming system 120, and transmits the light emitted from the image light forming system 120 to the projection system 130. Incorporate Here, although the block type PBS is exemplified as a member for focusing light with the image light forming system, a flat type PBS or a total reflection prism may be used.

The image light forming system 120 converts the light separated by the color wheel 114 into the image light according to the image data and enters the projection system 130. The image light forming system 120 is a digital light processing (DLP) method or an LCD (Liquid). Crystal Display) can be configured. Here, the DLP method generates an image by a digital micro-mirror device (DMD) chip in which a plurality of movable mirrors are integrated, and the LCD method means that an image is generated by a liquid crystal panel.

In the case of the DLP method, the image light generating system 120 includes a DMD chip. A plurality of movable mirrors are rotatably installed on the DMD chip, and the image light is generated by reflecting the block-type PBS. In addition, in the LCD method, the image light generating system 120 is configured as an LCD panel, and changes the phase of the incident light according to the on / off state to reflect the block-type PBS.

The projection system 130 is for projecting the light generated from the image light generation system 120 onto the screen, and a plurality of lenses are built to reduce various aberrations and to enlarge or reduce the image light.

In particular, the contrast ratio adjusting unit 140 including at least one blade as a light blocking structure for adjusting the contrast of the image light is installed inside the barrel of the projection system 130.

The contrast ratio adjusting unit 140 installed inside the barrel includes a frame having an image light passing hole, at least one blade provided on the frame, and a driving unit rotating the blade to adjust the open area of the image light passing hole. It includes.

Here, the drive unit is composed of a permanent magnet fixed to the lower portion of the blade, and an electromagnet for rotating the blade by the electromagnetic interaction with the permanent magnet, the electromagnet is to each of the anode of the permanent magnet It is arranged to face.

In addition, the electromagnet preferably comprises a core, a core protector which prevents the core from energizing, and determines a rotation angle of the blade, and a coil surrounding the core protector.

Here, the core protection part is made of a body portion, and the first and second plates formed on both ends of the body portion, it is preferable that the rotation angle of the blade is determined by the first plate. In other words, the permanent magnet attached to the lower portion of the blade is rotated by the interaction with the electromagnet, the movement of the blade is blocked by the first plate located on the outer side from the core protection portion This is determined.

In addition, the core protection unit is preferably formed integrally by the insert injection method.

2 is a cross-sectional view taken along the line II of FIG. 1 as an embodiment of the contrast ratio adjusting unit according to the present invention.

Contrast ratio adjustment unit according to the present invention is composed of a frame 132, at least one blade (141, 142) and the drive unit (145, 148).

The image light passing hole 133 is formed in the frame 132. The image light passing hole refers to a region through which image light generated by the image light generating system 120 of FIG. 1 passes.

The image light passing hole 133 may include a curved portion 133a and a straight portion 133b connecting both ends of the curved portion 133a. The curved portion 133a may be in the form of an arc having the same curvature. In this case, the image light passing hole 133 is similar to a semi-circular shape. In addition, the image light passing hole may be changed into various structures unlike the shape shown in FIG. 2.

At least one blade 141, 142 is provided on the frame 132 formed inside the barrel 131, and adjusts the contrast ratio by adjusting the open area of the image light passing hole.

The driving units 145 and 148 are permanent magnets 146 and 149 fixed to the lower part of the at least one blade 141 and 142) and electromagnets disposed to face the anodes of the permanent magnets 146 and 149, respectively. The electromagnetic interaction of 147 and 150 rotates the at least one blade 141, 142.

Here, the electromagnets 147 and 150 are wound around a pair of cores 147a and 150a disposed to face the anodes of the permanent magnets 146 and 149 and the pair of cores 147a and 150a, respectively. It may include a coil (147b, 150b) consisting of a coil wire of. However, unlike the present embodiment, two coil wires may be used for the coils 147b and 150b. In addition, the core may be formed of a magnetic material such as a silicon steel sheet, the core may have the same shape of the same size.

In addition, the frame 132 may include rotation axes 141b and 142b of the at least one blade 141 and 142.

On the other hand, the light blocking structure of the contrast ratio control unit according to the present invention may be at least one blade, each of which is driven individually by the ON / OFF (ON / OFF) drive. Therefore, if the number of blades is N, the contrast ratio adjusting step is 2 ^N , which makes it possible to further refine the contrast ratio, thereby improving image quality.

In particular, the contrast ratio adjustment unit according to the present invention may include a first blade 141 installed to rotate on one side of the frame as shown in Figure 2 and a second blade 142 installed to rotate on the other side of the frame, In this case, the first blade 141 and the second blade 142 may be driven individually by on / off driving. In this case, the contrast ratio adjustment unit according to the present invention may be divided into four contrast ratio adjustment steps.

Here, the first blade 141 may include a groove 141a formed in a shape corresponding to a portion of the straight portion 133b of the image light passing hole 133 and a portion of the curved portion 133a. In addition, the second blade 142 may include a groove 142a formed in a shape corresponding to a part of the curved portion 133a of the image light passing hole 133. Here, the first and second blades may be changed in various structures, unlike the shape shown in FIG.

Hereinafter, the driving unit in the contrast ratio adjustment unit according to the present invention will be described in detail with reference to the drawings.

Figure 3 is a schematic diagram showing an embodiment of a drive unit used in the contrast ratio adjustment unit according to the present invention, in particular, Figures 3 (a) and 3 (b) is a drive used in the contrast ratio adjustment unit according to the present invention As an embodiment of the unit shows the state before and after assembly, Figure 3 (c) shows the rotation angle regulation as an embodiment of the drive unit used in the contrast ratio adjustment unit according to the present invention.

First, in the driving unit used in the contrast ratio adjustment unit according to the present invention, the electromagnets 147 and 150 may include a core 147a and 150a, a core protection unit 151 and a coil surrounding the core protection unit 151 ( 147b, 150b).

Here, the core protector 151 prevents the core from energizing, that is, prevents the current flowing through the coils 147b and 150b from flowing through the cores 147a and 150a and determines the rotation angle of the blade. .

In addition, the core protection unit 151 may be composed of a first plate 151a and a second plate 151b. In particular, the rotation angles of the blades 141 and 142 may be determined by the first plate 151a. Can be.

In other words, referring to FIG. 3 (c), the permanent magnets 146 and 149 fixed to the lower portions of the blades 141 and 142 may be rotated by electromagnetic interaction with the electromagnets 147 and 150. At this time, the permanent magnets 146 and 149 fixed to the lower portions of the blades 141 and 142 are caught by the first plate 151a to determine the rotation angles of the blades 141 and 142. Therefore, in the contrast ratio adjustment unit according to the present invention, the rotation angle of the blade is determined by the interval B after the electromagnets 147 and 150 arranged to face the permanent magnets 146 and 149 are assembled.

On the other hand, in this case, the electromagnet is not easy to control the distance (A) from the fastening center of the electromagnet to the end of the electromagnet due to the reduction in the accuracy and tolerance of the assembly generated in the process of assembling the parts, the electromagnets The distance B after) is assembled may also be inaccurate, and the rotation angle control of the blade may be inaccurate.

Figure 4 is a schematic diagram showing another embodiment of the drive unit used in the contrast ratio adjustment unit according to the present invention, in particular, Figure 4 (a) to Figure 4 (c) is a drive unit used in the contrast ratio adjustment unit according to the present invention As another embodiment of the assembly process is shown, Figure 4 (d) shows the rotation angle regulation as another embodiment of the drive unit used in the contrast ratio control unit according to the present invention.

First, in the driving unit used in the contrast ratio adjustment unit according to the present invention, the electromagnets 147 and 150 may include a core 147a and 150a, a core protection unit 151 and a coil surrounding the core protection unit 151 ( 147b, 150b).

Here, the core protection unit 151 prevents the core from energizing, that is, prevents the current flowing through the coils 147b and 150b from flowing through the cores 147a and 150a and determines the rotation angle of the blade. .

In addition, the core protection part 151 may include a body part 151c, and a first plate 151a and a second plate 151b formed at both ends of the body part.

In addition, the core protection part 151 has a hole formed in the second plate 151b and the body part 151c, and the cores 147a and 150a are shown in FIG. 4 (b). Preferably, the second plate 151b is inserted into the body 151c.

In addition, the body 151c, the first plate 151a and the second plate 151b are preferably formed integrally. In this case, the core protection part 151 formed of the body part 151c, the first plate 151a, and the second plate 151b may be formed by an insert injection method.

In other words, the contrast ratio control unit according to the present invention can reduce the tolerances that may occur when the electromagnet is assembled by integrally forming the core protection unit 151 of the electromagnet, and in particular, by using the insert injection method Eggplants can be made of electromagnets.

In addition, in the contrast ratio adjustment unit according to the present invention, it is preferable that the rotation angles of the blades 141 and 142 are determined by the first plate 151a.

In other words, referring to FIG. 4 (d), the permanent magnets 146 and 149 fixed to the lower portions of the blades 141 and 142 may be rotated by electromagnetic interaction with the electromagnets 147 and 150. In this case, the movement of the permanent magnets 146 and 149 fixed to the lower portions of the blades 141 and 142 by the first plate 151a of the core protection unit 151 integrally formed by the insert injection method is limited. As a result, the rotation angles of the blades 141 and 142 are determined.

Therefore, the contrast ratio adjustment unit according to the present invention is easy to precise control of the distance (A ') from the fastening center of the electromagnet to the end of the electromagnet due to the core protection unit 151 integrally formed by the insert injection method, The distance B 'after the 147 and 150 are assembled can also be accurately controlled, so that the rotation angle of the blade can be accurately controlled.

As mentioned above, preferred embodiments of the present invention are disclosed for purposes of illustration, and those skilled in the art can improve and change various other embodiments within the spirit and technical scope of the present invention disclosed in the appended claims below. , Replacement or addition would be possible.

As described above, the contrast ratio control unit of the projection apparatus according to the present invention and the projection apparatus using the same in the assembly of the electromagnet itself by integrally forming the core protection portion of the electromagnet by insert injection in the drive unit for determining the light transmission area And the complexity is improved, and the rotation angle of the blade can be accurately controlled.

Claims (9)

A frame having an image light passing hole formed therein; At least one blade provided on the frame and configured to adjust an open area of the image light passing hole; And It includes a drive unit for rotating the blade, The drive unit is composed of a permanent magnet fixed to the lower portion of the blade, and an electromagnet disposed to face each of the anode of the permanent magnet, The electromagnet is And a core protector which prevents the core from being energized and determines the rotation angle of the blade, and a coil that surrounds the core protector. The method of claim 1, And the core protection part comprising a body part and first and second plates formed at both ends of the body part. The method of claim 2, The core protection unit has a hole formed in the second plate and the body portion, and the contrast ratio adjustment unit of the projection apparatus, characterized in that the core is inserted into the second plate and the body portion. The method of claim 2, And the body part and the first and second plates are integrally formed. The method of claim 2, Contrast ratio control unit of the projection apparatus, characterized in that the core protector is formed by the insert injection method. The method of claim 2, Contrast ratio adjustment unit of the projection device, characterized in that the rotation angle of the blade is determined by the first plate. An illumination system that aligns the light irradiated from the lamp to emit light having any one polarization component; An image light forming system for reflecting light incident from the illumination system and outputting the light as image light; At least one lens mounted inside a barrel including a frame in which an image light passing hole is formed, for projecting light generated by the image light forming system to a screen; At least one blade provided on the frame and configured to adjust an open area of the image light passing hole; And It includes a drive unit for rotating the blade, The drive unit is composed of a permanent magnet fixed to the lower portion of the blade, and an electromagnet disposed to face each of the anode of the permanent magnet, The electromagnet is And a core protector for preventing the core from energizing and determining the rotation angle of the blade, and a coil surrounding the core protector. The method of claim 7, wherein The core protector comprises a body and first and second plates formed at both ends of the body, and the rotation angle of the blade is determined by the first plate. The method of claim 8, The core protection unit is a projection apparatus, characterized in that formed integrally by the insert injection method.

Images