KR100863841B1 - Projection system - Google Patents

Abstract

TECHNICAL FIELD The present invention relates to a projection system, and more particularly, to an optical engine assembly structure of a projection system that simplifies the assembly structure of an optical engine mounted on a projection TV and facilitates repair and replacement of each component.

The projection system according to the present invention includes a lamp assembly in which white light is emitted, an illumination system in which light emitted from the lamp assembly is converted into colored light, and a synthesis system in which light passing through the illumination system is reflected or refracted to obtain a desired image. An optical engine including a projection lens unit configured to project an image transmitted from the synthesis system onto a screen; And an engine base on which the optical engine is seated, wherein the optical engine is detachably attached to the engine base in one assembly state.

By the projection system according to the present invention, the performance of the large-screen high-definition has the advantage that the overall volume of the projection system is slimmer.

Projection, total reflection, optical engine

Description

Projection system

1 is a cross-sectional view schematically showing a projection system according to the spirit of the present invention.

2 is an external perspective view of an optical engine according to the spirit of the present invention;

3 is a partially exploded perspective view of the optical engine;

4 is an exploded perspective view showing a state in which the optical engine according to the spirit of the present invention is coupled to the base.

5 is an exploded perspective view of the optical engine.

6 is an exploded perspective view showing a coupling state of the reflectometer constituting the optical engine according to the spirit of the present invention.

7 is a system diagram showing an image output process of the optical engine according to the inventive concept.

8 is a system diagram illustrating a path of light occurring in a reflectometer of a projection system in accordance with the teachings of the present invention.

9 is a perspective view showing a projection lens assembly of the projection system according to the spirit of the present invention.

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

1: projection system 10: optical engine unit

20: optical engine 21: lamp assembly

22: color wheel assembly 23: light tunnel housing

24: light tunnel assembly 25: condensing lens

26: DMD Assembly 27: Actuator

28: reflector case 29: folding mirror

30: total reflection prism 31: projection lens assembly

TECHNICAL FIELD The present invention relates to a projection system, and more particularly, to an optical engine assembly structure of a projection system that simplifies the assembly structure of an optical engine mounted on a projection television and facilitates repair and replacement of each component.

Recently, large-screen high-definition display devices have emerged as a major topic, and such large-screen high-definition display devices include CRT (Cathode Ray Tube) televisions, Liquid Crystal Display (LCD) televisions, Projection televisions, and Plasma Display Panel (PDP) televisions. It's coming out.

Among them, the demand for the projection television and the development of technology are actively made as one of the display apparatuses that satisfy the requirements of large screen high definition. The projection television includes a liquid crystal on silicon (LCOS) method using an LCD and a digital light porsessing (DLP) method using a digital micromirror device (DMD).

Recently, low-cost projection TVs using LCDs or DMDs have been in the spotlight. In particular, as the consumer's desire for high quality along with a large screen increases, the demand is increasing year by year, and the trend is particularly popular in the digital television market currently being trial broadcast.

In addition, as the use of computers and presentations using computers have been increasing in recent years, the use of projectors using LCDs or DMDs has also increased.

In general, a projection television adopts a method in which light generated by an optical engine mounted inside a cabinet is reflected and an image is projected on a screen.

In detail, an optical engine using a DMD includes a lamp that emits white light, a color wheel device that separates light emitted from the lamp into red, green, and blue light, an illumination system that collects light passing through the color wheel device; And a DMD for receiving a light passing through the illumination system to create a desired screen, and a projection lens to enlarge and project the image generated from the DMD onto the screen.

Conventional optical engines composed of a plurality of components as described above are generally bulky, and require high precision in the assembling process. In detail, in order to keep the angle and distance of the light emitted from the lamp constant, ultra precision is required in the assembly deviation between the parts and the dimensional tolerances of the parts separately in order to deliver them to the effective screen of the DMD. As a result, defects occurring during the production of the optical engine had to be reworked and repaired separately. For this reason, the assembly process has been complicated and the production efficiency has been reduced.

In addition, in the large display product market, where price competition is intensifying, it is difficult to secure price competitiveness with stability and precision of dimensions by applying unit components requiring ultra precision.

Therefore, there is a need for structural improvement for minimizing the parts management factor of the conventional structure and improving the convenience and reworkability of assembly. In addition, there is a need to improve the assembly position of components constituting the optical engine and the like to reduce the overall volume of the optical engine. In other words, it is urgently required to improve the above problems and to satisfy the quality of the entire optical engine and to secure a price competitiveness at the same time.

The present invention has been proposed to solve the above problems, by improving the assembly structure of the optical engine constituting the projection system, to simplify the assembly process, to provide a projection system that allows the overall volume of the optical engine to be slimmer. For the purpose of

It is also an object to provide a projection system in which the assembly structure of the optical engine is improved, so that the quality of the projection system remains the same or even better while the product price can be reduced.

Projection system according to the present invention for achieving the above object is a lamp assembly in which white light is emitted, an illumination system in which the light emitted from the lamp assembly is converted into colored light, and the light passing through the illumination system is reflected or refracted An optical engine including a synthesis system for obtaining a desired image and a projection lens unit for projecting an image transmitted from the synthesis system onto a screen; And an engine base on which the optical engine is seated, wherein the optical engine is detachably attached to the engine base in one assembly state.

In another aspect the projection system according to the invention comprises an engine base; A light tunnel housing seated on the engine base; A lamp assembly coupled to one side of the light tunnel housing; A light tunnel and a condensing lens seated in an assembly state opposite the lamp assembly; A reflectometer seated at an end of the condensing lens;

A DMD assembly positioned at one side of the reflectometer; and a projection lens assembly seated at a position opposite to the DMD assembly; wherein the components except the engine base are separately separated from each other or one assembly state from the engine base. Characterized in that can be separated.

By the above configuration, there is an advantage that the assembly process is improved and the production efficiency is increased while maintaining the performance of a large screen.

Hereinafter, specific embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the spirit of the present invention is not limited to the embodiments presented, and other embodiments included within the scope of other inventive inventions or the scope of the present invention can be easily made by adding, changing, or deleting other elements. I can suggest.

1 is a cross-sectional view schematically showing a projection system according to the spirit of the present invention.

Referring to FIG. 1, a projection system 1 according to the present invention includes a cabinet 2 forming an appearance, a screen 4 mounted on the front surface of the cabinet 2, and an optical seat mounted on a lower end of the cabinet 2. An engine unit 10 and a rearview mirror 3 mounted to the inner circumferential surface of the cabinet 2 to reflect the image emitted from the optical engine unit 10 onto the screen 4 are included.

In detail, the image screen formed and projected by the optical engine unit 10 is reflected by the rearview mirror 30. The reflected image is extended and projected onto the screen 4 so that the image screen is recognized by the user.

Hereinafter, the structure and function of each part of the optical engine unit 10 will be described in more detail with reference to the accompanying drawings.

2 is an external perspective view of an optical engine according to the inventive concept, and FIG. 3 is a partially exploded perspective view of the optical engine.

2 and 3, the optical engine unit 10 according to the present invention includes a base 11, an optical engine 20 mounted on the base 11, and an outer portion of the optical engine 20. Various parts to be mounted are included.

In detail, a power supply unit 15 for supplying an appropriate amount of power to the various electrical components constituting the optical engine unit 10 to the various components mounted on the outside of the optical engine 20, and the power supply unit 15 ) And a lamp cooling fan assembly 14 for cooling the lamp (to be described later) constituting the optical engine 20, and a ballast mounted to one side of the base 11 13), a projection lens cap 17 surrounding the projection lens (to be described later) constituting the optical engine 20, and a DMD fan for cooling the DMD panel (to be described later) constituting the optical engine 20. (12) is included.

In more detail, the power supply unit 15 is a switching mode power supply (SMPS), and is a modular power supply unit that converts electricity supplied from the outside to match the electric device. In addition, the power supply unit 15 controls the intermittent control at a high frequency of a commercial frequency or higher and mitigates the impact by using semiconductor switching characteristics.

In addition, the ballast 13 functions to apply a high voltage when the lamp constituting the optical engine 20 is turned on and to appropriately adjust the current so that an overcurrent does not flow after the lamp is turned on.

As shown in FIG. 3, in the case of the optical engine unit 10 according to the present invention, each part except for the optical engine 20 may be independently separated from the base 11. Thus, the optical engine 20 is mounted to the base 11, and then each of the components mentioned above are coupled to the base 11.

4 is an exploded perspective view illustrating a state in which an optical engine according to the spirit of the present invention is coupled to a base, and FIG. 5 is an exploded perspective view of the optical engine.

Referring to FIG. 4, the optical engine 20 for making an image screen in the optical engine unit 10 according to the present invention may be integrally separated from the base 11.

In detail, the optical engine 20 assembly is completely separated by removing only eight fastening members that allow the optical engine 20 assembly to be fixed to the base 11. Therefore, there is an advantage that the service is easily made and the disassembly and assembly process is very simple.

In addition, in order for the optical engine 20 assembly to be secured to the base 11, it is not necessary to first have the components of the optical engine 20 assembled to the base 11. That is, the optical engine 20 is assembled separately, and then integrally mounted on the base 11.

Referring to FIG. 5, the optical engine 20 according to the present invention includes a lamp assembly 21 in which white light is generated by a high voltage supplied by the ballast 13, and unpolarized light emitted from the lamp assembly 21. A color wheel assembly 22 for separating the red, green, and blue, a light tunnel assembly 24 for uniformly making red, green, and blue separated light while passing through the color wheel assembly 22; A condensing lens 25 through which the uniform light is collected while passing through the light tunnel assembly 24, a folding mirror 29 reflecting light passing through the condensing lens 25, and A total reflection prism 30 for reflecting the light reflected by the folding mirror 29 again, a DMD assembly 26 for collecting the light reflected by the total reflection prism 30 to form image information, and the DMD assembly ( Reflected from 26 An actuator 27 for irradiating by doubling the number of pixels of light and a projection lens 31 for enlarging the light passing through the actuator 27 are included. Here, the assembly of the lamp assembly 21, the color wheel assembly 22, the light tunnel assembly 24 and the condensing lens 25 is called an illumination system. The aggregate of the folding mirror 29 and the total reflection prism 30 is called a reflectometer, and the aggregate of the reflectometer and the DMD assembly 26 is called a synthetic system.

In more detail, the lamp assembly 21 includes a lamp 212 that emits white light and a lamp case 211 that protects the lamp 212. In addition, the reflector of the lamp 212 serves to change the light emitted from the burner of the lamp is reflected to focus at a certain distance, that is, the focal length.

In addition, the color wheel assembly 22 may be divided into red, green, and blue color wheels (also referred to as 221: RGB color filters) and rotate at high speed. A motor 223 driving the wheel 221 and a heat dissipation fin 222 for cooling the motor 223.

In detail, light emitted from the lamp 212 by the reflector of the lamp 212 is focused on the surface of the color wheel 221. In addition, the light collected by the color wheel 221 passes through the color wheel 221 and turns any color of red, blue, and green. Here, the color wheel 221 has a disk shape having a predetermined diameter, the disk is divided into red, green, blue. Accordingly, the unpolarized light reflected by the reflector has one of red, blue, and green colors due to the color of the color wheel located at the moment of condensing.

In addition, the color wheel assembly 22 and the light tunnel assembly 24 are housed inside the light tunnel housing 23.

In addition, the light tunnel assembly 24 is also called a rod lens, and serves to uniformly make colored light passing through the color wheel 221.

In detail, the light tunnel assembly 24 is formed by joining four small, long rectangular bar mirrors facing each other. The light passing through the color wheel assembly 22 is diffusely reflected while passing through the light tunnel, and the brightness distribution is uniform.

In addition, the condensing lens 25 performs a function of collecting red, green, and blue light uniformed while passing through the light tunnel assembly 24 to the DMD elements constituting the DMD assembly 26. do.

The total reflection prism 30 may also be referred to as a total internal reflection (TIR) prism, and a prism having a large refractive index and a prism having a relatively small refractive index are bonded to each other. The light irradiated from the condensing lens 25 is totally reflected or transmitted according to the incident angle due to the difference in refractive index.

In detail, each object has its own refractive index, and the difference in refractive index determines the critical angle at which light is totally reflected or transmitted.

Therefore, light incident at an angle greater than or equal to the critical angle is totally reflected by the total reflection prism 30, and light incident at an angle smaller than or equal to the critical angle passes through the total reflection prism 30. The function of the total reflection prism 30 will be described in detail with reference to the accompanying drawings.

In addition, the DMD assembly (Digital Micro-mirror Device Assembly) 26 is composed of a DMD panel 33 (see FIG. 7) and a driver board in which the DMD panel 33 is accommodated. In detail, the driver board is a device for controlling the driving of the ballast and the color wheel or controlling the image.

On the other hand, the DMD panel 33 is designed so that a minute mirror of the same amount as the resolution of the display is arranged so as to have a one-to-one correspondence with the screen.

In detail, the DMD panel 33 determines whether the red, green, and blue light transmitted through the total reflection prism 30 is to be directed toward the screen or discarded out of the screen. The DMD panel 33 is mounted in a complementary metal oxide semiconductor (CMOS) memory and driven by a signal transmitted from the CMOS memory.

In more detail, the micromirror constituting the DMD panel 33 is manufactured in the form of a fine diamond-shaped pixel of 16 μm in width and length, and tilted by ± 10 degrees according to a signal transmitted from the CMOS, so that the total reflection prism ( Light passing through 30 is reflected toward the screen or thrown out of the screen.

In addition, the actuator 27 is disposed between the DMD panel 33 and the projection lens 31, and a mirror is mounted at the center portion. In detail, the actuator 27 performs the function of doubling the number of pixels of the image signal by dividing the image signal emitted from the DMD panel 33 by half a frame and refracting it. Due to the refraction characteristics of the mirror, the resolution of the screen is increased. In addition, the actuator includes a transmission type and a reflection type.

In addition, the projection lens assembly 31 functions to enlarge the image passing through the actuator 27 toward the rearview mirror 3. Details of the projection lens assembly 31 will be described in detail with reference to the accompanying drawings.

In the optical engine 20 having the above-described configuration, the actuator 27, the total reflection prism 30, and the folding mirror 29 are inserted from different surfaces of the reflector case 28 so that one reflectometer may be used. Configure. The color wheel assembly 22 and the light tunnel assembly 24 are accommodated in the light tunnel housing 23 to constitute another assembly. In addition, the lamp assembly 210 forms a separate assembly together with the lamp 212 mounted inside the lamp case 211, and the light tunnel housing 23 is in close contact with the front of the lamp assembly 21. .

As described above, since a plurality of parts form a single assembly, there is an advantage that parts replacement and service are easily performed.

6 is an exploded perspective view illustrating a coupling state of a reflectometer constituting an optical engine according to the inventive concept.

Referring to FIG. 6, the reflectometer constituting the optical engine unit 10 according to the present invention includes a reflectometer case 28, a folding mirror 29 inserted from a side of the reflectometer case 28, and An actuator 27 inserted from the upper surface of the reflector case 28 and a total reflection prism 30 inserted from the front surface of the reflector case 28 are included.

In detail, a prism seat 281 in which the total reflection prism 30 is mounted is formed in the reflector case 28. In addition, a DMD hole 285 is formed on a surface on which the prism seating portion 281 is formed, that is, a rear surface of the reflector case 28. Accordingly, the light totally reflected by the total reflection prism 30 is projected onto the DMD panel 33 through the DMD hole 285. In addition, a folding mirror insertion hole 283 for inserting the folding mirror 29 is formed at a side of the reflector case 28. In addition, an actuator insertion hole 282 for inserting the actuator 27 is formed in an upper surface of the reflector case 28. In addition, a prism insertion hole 284 for inserting the total reflection prism 30 is formed on the front surface of the reflectometer case 28.

The assembling process of the reflectometer having the above configuration will be described. First, the total reflection prism 30 is inserted through the prism insertion hole 284. The total reflection prism 930 is fixed to the prism seating surface 281.

In addition, the user allows the actuator 27 to be inserted into the reflectometer case 28 through the actuator insertion hole 282. Then, the folding mirror 29 is inserted into the reflectometer case 28 through the folding mirror insertion hole 283. Here, the order of insertion of the folding mirror 29 and the actuator 29 may be performed first. The DMD assembly 26 is located at the rear of the reflector case 28, and the projection lens assembly 31 is located at the front of the reflector case 28.

By the assembly structure as described above, since the folding mirror 29, the actuator 27 and the total reflection prism 30 form one assembly, disassembly and assembly are very easy. In addition, since the respective parts are inserted from different sides of the reflectometer case 28, the assembling and disassembling of the individual parts can be easily performed.

7 is a system diagram illustrating an image output process of an optical engine according to the inventive concept.

Referring to FIG. 7, the image output process occurring in the projection system according to the present invention will be described in detail. First, power is applied to the lamp 212 to emit white light. The emitted white light is focused on the color wheel assembly 22 to have any one color of red, green, and blue. Here, the front of the color wheel assembly 22 is equipped with a UV filter 32, so that only visible light required by the system is output, thereby reducing the fatigue caused by heat.

In addition, light passing through the color wheel assembly 22 becomes uniform while passing through the light tunnel assembly 24 and then enters the condensing lens 25. Light emitted from the condensing lens 25 is reflected by the folding mirror 29. In addition, the light reflected by the folding mirror 29 is totally reflected by the total reflection prism 30 and condensed on the DMD panel 33. In addition, the light condensed on the DMD panel 33 obtains a desired image by the tilting action of the fine mirror. The obtained image is transmitted through the total reflection prism 30. In addition, the image transmitted through the total reflection prism 30 is smoothly changed by doubling the pixel while passing through the actuator 27. The image passing through the actuator 27 is incident to the projection lens 31, and the image is enlarged from the projection lens 31 and exited to the rearview mirror 3. The light incident on the rearview mirror 3 is reflected and reflected on the screen 4.

8 is a system diagram illustrating a path of light generated in a reflectometer of a projection system according to the inventive concept.

Referring to FIG. 8, in the total reflection prism 30 constituting the optical engine unit 10 of the projection system 1 according to the present invention, a primary prism 301 and a secondary prism 302 having different refractive indices are bonded to each other. It is formed. Light is totally reflected at the total reflection surface 303 formed by the junction of the primary prism 301 and the secondary prism 302. Here, an air gap is formed in the total reflection surface 303 to which the two prisms are bonded, and a difference in refractive index occurs due to the air gap, and a critical angle is formed by the change of the refractive index. Therefore, light incident at an angle greater than or equal to the critical angle is totally reflected at the total reflection surface 303, and light incident at an angle less than or equal to the critical angle passes through the total reflection surface 303.

On the other hand, the light passing through the condensing lens 25 hits the folding mirror 29 and is reflected toward the total reflection prism 30. The light reflected by the primary prism 302 of the total reflection prism 30 is totally reflected at the total reflection surface 303 to impinge on the DMD panel 33. The light incident on the DMD panel 33 is selected to obtain a desired image. Then, the light taken by the tilting action of the micromirror constituting the DMD panel 33 is reflected again to pass through the total reflection surface 303 of the total reflection prism 30. In addition, the light transmitted through the total reflection surface 303 passes through the actuator 27, and the pixel is doubled. Then, the light containing the image information passing through the actuator 27 is incident to the projection lens 31.

9 is a perspective view showing a projection lens assembly of the projection system according to the spirit of the present invention.

Referring to FIG. 9, the projection lens assembly 31 constituting the optical engine unit 10 of the projection system 1 according to the present invention includes a first lens 311 for condensing an image passing through the actuator 27. And a reflection mirror 314 for changing a path of the image collected by the first lens 311 and an image reflected by the reflection mirror 314 by diffusing and condensing multiple times in multiple times, A second lens 312 for allowing the enlarged image to form on the screen 4 and an aperture 313 for removing unnecessary light from the light incident on the first lens 311 are included. In detail, when the light passing through the actuator 27 is incident on the first lens 311 in the form of a desired image, not only the light for displaying the desired image is incident on the screen 4, but also unnecessary light. Thus, the aperture 313 is mounted in order to prevent such unnecessary light from being excessively incident on the screen 4 so that the entire screen becomes brighter than necessary.

In more detail, the aperture 313 allows only necessary light to be incident on the light incident to the first lens 311, and functions to mask unnecessary light.

As described above, the optical engine unit 10 of the projection system 1 according to the present invention includes an optical engine 20 mounted on the base 11 and various types mounted around the optical engine 20. The parts can be assembled and disassembled independently of each other. In addition, the optical engine 20 may be mounted or detached from the base 11 in a single assembly form.

In addition, since the folding mirror 29, the actuator 27 and the total reflection prism 30 are assembled in one case and act as one assembly, there is an advantage in that the assembly and disassembly of the component are very simple. . The folding mirror 29, the actuator 27, and the total reflection prism 30 are not in a mutually fastening relationship, and each of them is coupled to the reflectometer case 28 only. Thus, separate separations are possible without affecting the different parts. In addition, the reflectometer case 28 can also be separated from the base 11 separately.

In addition, since the color wheel assembly 22 is also coupled to the light trough housing 23, individual separation is possible without affecting other components, that is, the light tunnel assembly 24.

By such a configuration, the assembler allows the light tunnel housing 23 to be seated on the base 11, and then the lamp assembly 21 is brought into close contact with the front surface of the light tunnel housing 23. Then, the color wheel assembly 22 is inserted from one side of the light tunnel housing 23. Then, the light tunnel assembly 24 and the condensing lens 25 assembly are seated at the rear of the light tunnel housing 23. Here, the light tunnel assembly 24 is inserted into the light tunnel housing 24.

The assembler also allows the reflectometer assembly to be seated at the rear end of the condensing lens 25. Then, the DMD assembly 26 is seated in the direction crossing from the condensing lens 25. Then, the projection lens assembly 31 is assembled in a direction opposite to the DMD assembly 26.

By the projection system according to the present invention having the above configuration, there is an advantage that the overall volume of the projection system is slim without changing the performance of the large screen.

In addition, by improving the optical engine assembly structure of the projection system according to the present invention, the overall number of assembly processes is reduced, there is an effect that the productivity is improved.

In addition, by improving the optical engine assembly structure of the projection system according to the present invention, the replacement or repair of parts is made very easy, there is an advantage that the service efficiency is increased.

In addition, by the projection system according to the present invention, the number of parts is reduced by simplifying the assembly process, there is an advantage that the price competitiveness of the product is secured.

In addition, when any one of the components constituting the optical engine is replaced or repaired, there is an advantage in that the service efficiency is improved because only the specific component in which the failure occurs can be replaced without disassembling the entire engine.

Claims (9)

A lamp assembly in which white light is emitted, an illumination system in which light emitted from the lamp assembly is converted into colored light, a synthesis system in which light passing through the illumination system is reflected or refracted to obtain a desired image, and an image transmitted from the synthesis system. An optical engine including a projection lens unit configured to project on the screen; And An engine base on which the optical engine is mounted; And the optical engine is attached to and detached from the engine base as an assembly. The method of claim 1, The synthesis system includes a DMD assembly, and a reflectometer for reflecting or refracting light passing through the illumination system to focus on the DMD assembly, The reflectometer includes a folding mirror for reflecting light passing through the illumination system, a total reflection prism for reflecting light reflected by the folding mirror to the DMD assembly, and an actuator for refracting transmission of light reflected from the DMD assembly. Projection system comprising a. The method of claim 2, A case for accommodating the folding mirror and the total reflection prism and the actuator, The case may be formed of a plurality of surfaces in which holes of a predetermined size are formed, and each of the folding mirror, the total reflection prism, and the actuator may be inserted through a different surface among a plurality of surfaces constituting the case. Projection system. delete The method of claim 2, And the reflectometer is separate from the engine base by removing the fastening member for engagement with the engine base. Engine base; A light tunnel housing coupled to the engine base by a fastening member; A lamp assembly coupled to one side of the light tunnel housing; A light tunnel and a condensing lens seated in an assembly state at a side opposite to one side of the light tunnel housing to which the lamp assembly is coupled; A reflectometer seated at an end of the condensing lens; A DMD assembly located at one side of the reflectometer; and And a projection lens assembly seated at a position opposite to the DMD assembly. The component except for the engine base is a projection system, characterized in that separate from each other from the engine base or in one assembly state. The method of claim 6, The light tunnel housing is a projection system, characterized in that the hole is further formed the size of the color wheel assembly can be inserted so that the color wheel assembly can be separated and assembled separately. The method of claim 6, The reflectometer includes a case having a plurality of surfaces having a hole having a predetermined size, an actuator inserted from an upper surface of the case, a folding mirror inserted from a side of the case, and a surface adjacent to a surface into which the folding mirror is inserted. Projection system including a total reflection prism inserted into the other side of the case. The method of claim 8, And the actuator, the folding mirror, and the total reflection prism are coupled only to the case without a fastening relationship therebetween.

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