KR20060124034A - Optical light source for a color image projector - Google Patents

Abstract

An illumination optical system of a color image projection apparatus is provided to more improve optical efficiency by restraining lost light by the removal of a color mixing optical device. A rotary wheel(120) is installed to be rotated and driven by a driving motor(101). LEDs(Light Emitting Diodes)(11-13), disposed at a uniform interval in one side of the rotary wheel(120), generate and emit color lights of inter-different wavelength zones. A rod lens(130), disposed at a light emitting side of the LED to alternately locate and arrange one of a plurality of the LEDs(11-13) on the same axis, concentrates the color light emitted from the arranged LED and transmits the concentrated color light to an image generating part.

Description

Optical light source for color image projection apparatus {Optical light source for a color image projector}

1 and 2 are schematic configuration diagrams showing an illumination optical system of a conventional color image projection apparatus, respectively;

3 is a schematic configuration diagram showing an illumination optical system of a color image projection apparatus according to the present invention;

4 is a schematic plan view showing an extract of the rotating wheel of FIG.

FIG. 5 is a schematic perspective view showing an extract of the light source and the condenser lens of FIG. 3; FIG.

<Description of Symbols for Main Parts of Drawings>

11, 12, 13 ... LED light source 100 ... Lighting optical system

Drive motor 110 ... Rotating wheel

120 Condenser Lens 130 Rod Lens

140 ... Image generation means 150 ... Projection lens unit

The present invention relates to an image projection apparatus such as a projection television set or a projector, and more particularly, to an illumination optical system of a color image projection apparatus using a light emitting element such as a light emitting diode (LED) or a laser diode (LD) as a light source. It is about.

For example, a projection television set or a projector that displays desired image information on a large screen by projecting an image generated by an image generating means such as a digital mirror device (DMD) or a liquid crystal display (LCD) onto a screen using a separate light source. The same image projection value has a large influence on the image quality of the illumination optical system having a light source and a condenser lens. In general, a high-pressure discharge lamp such as a mercury lamp, a metal halide lamp, a xenon lamp, or the like is mainly used as a light source used in an illumination optical system of an image projection apparatus.

In recent years, however, light emitting diodes (LEDs), which have been greatly improved in brightness, have been used as light sources for simple lighting devices such as flashlights and traffic lights and automobile lighting devices, as well as lighting sources for video projection devices. Attempts are being made to expand and apply. Such an LED light source has excellent color reproducibility compared to a discharge lamp, and in particular, it is advantageous to realize a mobile image projection device that is easy to carry because it is advantageous for long life and miniaturization.

As shown in FIG. 1, the illumination optical system of the conventional color image projection apparatus using the LED as a light source for miniaturization and long life is shown as red, green, and blue (B) light sources, respectively. LED 11, 12 and 13 emitting color light beams of the color and color light beams emitted from the LEDs 11, 12 and 13, respectively, so as to emit light in a state in which the divergence angle is reduced. X as color mixing optical means for selectively reflecting and / or transmitting a plurality of condensing lenses 20 having a funnel-shaped structure and light beams of specific polarization components of the light beams respectively emitted from the condensing lenses 20 And a rod lens 40 as a light mixing means for focusing, diverging or reflecting the polarized beams routed by the X-cube prism 30 and mixing them into uniform light. Here, reference numeral 10 in the drawings denotes a substrate for forming the light source package by mounting the LEDs 11, 12, 13 and the condenser lens 20, respectively.

Meanwhile, FIG. 2 illustrates an illumination optical system of another conventional color image projection apparatus, and the color mixing optical means and the light mixing means are respectively a band pass filter 50 and a light tunnel 60. It has a configuration replaced with). Here, the same reference numerals as the reference numerals of the drawings shown above represent the same components.

According to the illumination optical system of the conventional color image projection apparatus having the configuration as described above, since the light beams respectively emitted from the LEDs 11, 12, 13 are unpolarized with a relatively large incident angle, the X-cube prism 30 and the band pass filter (Band pass filter) 50 has a problem that the light efficiency of the illumination is significantly lowered as the loss of light increases due to a decrease in the transmission / reflectance.

Accordingly, the present invention has been made to solve the problems of the illumination optical system of the conventional color image projection apparatus as described above, and an object of the present invention is to suppress the lost light by the exclusion of color mixing optical means to reduce the light efficiency. It is to provide an illumination optical system of a color image projection apparatus further improved.

Another object of the present invention is to provide a color image projection value which is more effective for improving image quality, long life, and miniaturization by improving light efficiency by using an illumination optical system for achieving the above object.

In order to achieve the above object, the illumination optical system of the color image projection apparatus according to the present invention includes a drive source; A rotating wheel installed to rotate by the drive source; A plurality of light emitting elements disposed on one surface of the rotating wheel at equal intervals to generate and emit color light of different wavelength bands, respectively; The plurality of light emitting elements are alternately arranged on the light output side of the light emitting element such that any one of them is aligned coaxially to focus the color light emitted from the coaxially aligned light emitting element for delivering to the image generating means Optical means; characterized in that it comprises a.

In order to achieve the above object, a color image projecting device according to the present invention includes image generating means for generating image light using illumination light emitted from an illumination optical system, and image light generated by the image generating means on a screen. A color image projection apparatus comprising a projection optical system for causing an enlarged projection, the illumination optical system comprising: a drive source; A rotating wheel installed to rotate by the drive source; A plurality of light emitting elements disposed on one surface of the rotating wheel at equal intervals to generate and emit color light of different wavelength bands, respectively; The plurality of light emitting elements are alternately arranged on the light output side of the light emitting element such that any one of them is aligned coaxially to focus the color light emitted from the coaxially aligned light emitting element for delivering to the image generating means Optical means; characterized in that it comprises a.

In the color image projection apparatus and illumination optical system according to the present invention having the configuration as described above, the rotation wheel is controlled to rotate and drive in steps of predetermined intervals in synchronization with the image implementation signal applied to the image generating means. .

According to the present invention, it is preferable that the optical means is provided with a rod lens, and a light condensing lens for injecting the rod lens in the state of reducing the divergence angle of the emitted light is provided on the light output side of the light emitting device. Do.

According to an aspect of the present invention, the light emitting device may be provided with any one selected from among three LEDs and LDs that emit red light, green light, and blue light, respectively.

According to another aspect of the present invention, the light emitting device may be installed such that any one selected from a plurality of pairs of LEDs and LDs that emit and emit red light, green light, and blue light are alternately arranged at equal intervals. .

Hereinafter, a color image projection apparatus and an illumination optical system thereof according to a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

3 and 4, the color image projection apparatus and the illumination optical system 100 according to the present invention are red (R), green (R) on the rotary wheel 110 installed to drive rotation by the drive motor 101 G) and the LEDs 11, 12 and 13 that generate and emit the color light beams of blue (B) are arranged at equal intervals, and the color light beams emitted from the LEDs 11, 12 and 13, respectively, The single rod lens 130 is configured to alternately focus to be incident on the image generating means 140 such as a DMD or LCD as illumination light to generate color image light.

The configuration as described above excludes color mixing optical systems such as X-cube prism or band-pass filter, which are light deterioration factors, in the illumination optical system of the conventional image projection apparatus, and has a constitutive feature that can further improve the light utilization efficiency. It is.

According to the present invention, the rotating wheel 120 is controlled to rotate in steps of predetermined intervals in synchronization with the image realization signal applied to the image generating means 140 by the control of the main controller (C).

Accordingly, the LEDs 11, 12 and 13 are alternately arranged so that any one of them is arranged coaxially with the rod lens 130.

According to one aspect of the invention, the rotary wheel 110 may be provided with a laser diode (hereinafter referred to as LD) for generating red light, green light and blue light as a light source.

On the other hand, the LEDs 11, 12, 13, or LDs (not shown) may be alternately arranged at four or six equal intervals.

On the other hand, the light exit side of the LED (11) 12, 13 is provided with a condenser lens 120 having a funnel-shaped structure, respectively, as shown in FIG. Here, reference numeral 10 in the drawings denotes a substrate for forming the light source package by mounting the LEDs 11, 12, 13 and the condenser lens 120, respectively.

As shown, the condenser lens 120 is formed to have a funnel shape or a tapered cylindrical shape whose outer diameter is gradually inclined from the light incidence side to the light output side, so that the light exit face is formed wider than the light incidence plane. The condensing lens 120 focuses the exiting light emitted from the LEDs 11, 12, 13, and enters the rod lens 130 in a state in which the divergence angle is reduced. By suppressing the minimum to the function to improve the light efficiency more.

The rod lens 130 mixes the light beam incident from the condensing lens 120 into uniform light by focusing, diverging, or reflecting the light beam and enters the image generating means 140 as illumination light. As a result, the color image generated by the image generating unit 140 is enlarged and projected on the screen by the projection lens unit 300 to display a desired image.

Hereinafter, the operation of the color image projection apparatus and the illumination optical system 100 according to the present invention having the configuration as described above will be described in detail with reference to the accompanying drawings.

First, the rotating wheel 110 is driven by the control of the main controller C according to the driving operation of the image projection apparatus. In this case, the rotation wheel 110 is controlled to rotate in steps of predetermined intervals in synchronization with the image realization signal applied to the image generating means 140. As a result, the LEDs 11, 12 and 13 are alternately positioned so that any one of them is arranged coaxially with the rod lens 130. That is, while the red signal is applied to the image generating means 140, the LED 11 which emits the red light beam is positioned to be coaxially arranged in a state close to the light incident surface of the rod lens 130. In addition, while the green signal is applied to the image generating means 140, the LED 12 which emits the green light beam is positioned to be disposed coaxially in a state close to the light incident surface of the rod lens 130. . In addition, when the blue signal is applied, the LED 13 emitting the blue light beam is positioned to be coaxially disposed in a state close to the light incident surface of the rod lens 130.

On the other hand, while the color light is changed while a signal corresponding to each color is applied, the signal has a change time (spoke time).

Accordingly, by rotating the rotating wheel 110 step by step during the conversion time, an LED that generates and emits a color light beam matching the applied color image signal is disposed coaxially with the rod lens 130. In this case, as the LED emits a light beam of a corresponding color by applying power, the rod lens 130 generates the image by mixing the light beam incident from the condenser lens 120 into uniform light by focusing, diverging, or reflecting. Incident to the means 140. The image generating means 140 generates color image light by using the incident illumination light, and the desired image is displayed by projecting the image light on the screen by the projection lens unit 300.

Therefore, the image projection apparatus and the illumination optical system according to the present invention, which have the same function as the above-described configuration, have an optical efficiency by eliminating an existing color mixing optical system such as an X-cube prism or a bandpass filter, which is a light efficiency deterioration factor. It is possible to implement a color image in a more improved state.

As described above, according to the image projection apparatus and the illumination optical system according to the present invention, by suppressing the loss of light by eliminating the color mixing optical means provided in the existing illumination optical system can further improve the light efficiency, More effective effects can be obtained for improving image quality, longevity and miniaturization.

The present invention is not limited to the above-described specific preferred embodiments, and various modifications can be made by those skilled in the art without departing from the gist of the present invention as claimed in the claims. .

Claims (12)

A drive source; A rotating wheel installed to rotate by the drive source; A plurality of light emitting elements disposed on one surface of the rotating wheel at equal intervals to generate and emit color light of different wavelength bands, respectively; The plurality of light emitting elements are alternately arranged on the light output side of the light emitting element such that any one of them is aligned coaxially to focus the color light emitted from the coaxially aligned light emitting element for delivering to the image generating means The optical system of the color projection apparatus comprising a; optical means. The method of claim 1, The rotating wheel is an optical system of the color projection apparatus, characterized in that the rotation drive in synchronization with the image implementation signal applied to the image generating means in a step unit of a predetermined interval. The method of claim 1, The light emitting device is an illumination optical system of a color image projection apparatus, characterized in that any one selected from among three LEDs and LD to generate and emit red light, green light and blue light, respectively. The method of claim 1, The light emitting device is an illumination optical system of a color image projecting device, characterized in that any one selected from a plurality of pairs of LEDs and LDs generating and emitting red light, green light, and blue light are alternately arranged at equal intervals. . The method of claim 1, The optical means is an illumination optical system of a color image projection apparatus, characterized in that the rod lens is installed. The method of claim 1, And a condenser lens on the light exit side of the light emitting device for condensing the diverging angle of the outgoing light into the optical means. A color image projection apparatus comprising: image generating means for generating image light by using illumination light emitted from an illumination optical system; and a projection optical system for expanding and projecting the image light generated by the image generating means on a screen. Illumination optical system, A drive source; A rotating wheel installed to rotate by the drive source; A plurality of light emitting elements disposed on one surface of the rotating wheel at equal intervals to generate and emit color light of different wavelength bands, respectively; The plurality of light emitting elements are alternately arranged on the light output side of the light emitting element such that any one of them is aligned coaxially to focus the color light emitted from the coaxially aligned light emitting element for delivering to the image generating means Color image projection apparatus comprising a; optical means. The method of claim 7, wherein The rotating wheel is a color image projection apparatus, characterized in that for driving in rotation in steps of predetermined intervals in synchronization with the image implementation signal applied to the image generating means. The method of claim 7, wherein The light emitting device is a color image projection apparatus, characterized in that any one selected from among three LED and LD for generating and emitting red light, green light and blue light, respectively. The method of claim 7, wherein The light emitting device is a color image projection apparatus, characterized in that any one selected from a plurality of pairs of LED and LD for generating red light, green light and blue light are alternately arranged at equal intervals. The method of claim 7, wherein The optical means is a color image projection apparatus, characterized in that the rod lens is installed. The method of claim 7, wherein And a condensing lens for incident on the optical means on the light exit side of the light emitting element with the divergence angle of the outgoing light reduced.

Images