JP6221551B2 - Light emitting device - Google Patents

Description

  The present invention relates to a light emitting device using a plurality of light sources having different emission colors.

  In a light emitting device used for an illumination device, a display, a projector, or the like, light of a desired color is obtained by combining a plurality of light sources having different emission colors (for example, Patent Document 1). The color of light is determined by the mixing ratio of R (red), G (green), and B (blue).

  The color of light can be expressed using, for example, the XY chromaticity diagram shown in FIG. The XY chromaticity diagram represents colors in the XY coordinate space, with the X axis indicating the ratio of R (red) and the Y axis indicating the ratio of G (green). The ratio of B (blue) is a value obtained by subtracting the sum of the ratios of R and G from 1. The bell-shaped region on the XY chromaticity diagram represents all the colors, and the boundary (outline) of the region is a monochromatic light with a wavelength of 380 nm to 780 nm (purple to red). The portion inside the boundary line represents multicolor light that is a combination of monochromatic light (for example, Non-Patent Documents 1 and 2).

  The two points (R) and (B) shown on the XY chromaticity diagram in FIG. 1 (hereinafter, the points on the XY chromaticity diagram are referred to as “chromaticity points”) are respectively the colors of light emitted by the red light source, When the color of light emitted from a blue light source corresponds to the color range (color gamut) of light obtained by combining these two light sources, the chromaticity point (R) and chromaticity point (B) are connected. It becomes a straight line. By adjusting the light quantity ratio (mixing ratio) of each light source, light of any color (mixed color light) on the straight line can be obtained.

  Furthermore, by adding a green light source that emits light indicated by the chromaticity point (G), the range connecting the three chromaticity points (R), (G), and (B) as shown in FIG. can do.

Japanese Unexamined Patent Publication No. 2009-49000

裳 華 房 株式会社, "Color Diagram", [online], December 17, 2012, Internet <URL: http://www.shokabo.co.jp/sp_opt/spectrum/color3/ color-d.htm> Boss International, "Liquid Crystal Glossary", [online], December 17, 2012, Internet <URL: http: //www.boss-int.com/Develop/sheet/lcdchk02.html>

  In general, light emitted from a lamp, LED, or the like used as a light source is not monochromatic light but multicolor light having a certain spread in the emission spectrum. The chromaticity point corresponding to such multicolor light is located inside the spectrum locus. Since the color gamut based on these chromaticity points is narrower than the area surrounded by the boundary line, there are colors that cannot be obtained on the XY chromaticity diagram in a light emitting device using a lamp, LED, or the like as a light source. .

  In addition, even if a plurality of light sources with narrow emission spectrum widths such that chromaticity points are located near the spectrum locus, in order to match the region connecting these chromaticity points with the bell-shaped region, Many light sources with different colored light are required, which is not realistic.

  The problem to be solved by the present invention is to provide a light emitting device capable of obtaining all the colors including the color near the boundary line on the XY chromaticity diagram, which cannot be obtained by the conventional light emitting device. That is.

The light emitting device of the present invention made to solve the above problems is
Wavelength setting means for setting a first wavelength and a second wavelength that is different from the first wavelength;
First monochromatic light extraction means for extracting monochromatic light of the first wavelength from multicolor light emitted from a light source;
Second monochromatic light extraction means for extracting monochromatic light of the second wavelength from multicolor light emitted from a light source;
Color mixing means for mixing the monochromatic light of the first wavelength and the monochromatic light of the second wavelength in a color mixing unit;
A mixing ratio adjusting unit that adjusts a mixing ratio of the monochromatic light of the first wavelength and the monochromatic light of the second wavelength mixed by the color mixing unit;
I have a,
The color mixing unit includes a first optical fiber disposed so that the monochromatic light having the first wavelength extracted by the first monochromatic light extraction unit is incident from one end thereof, and the other end of the first optical fiber. A first color mixing unit comprising a first lens for condensing the monochromatic light of the first wavelength emitted from the unit in the color mixing unit, and the monochromatic light of the second wavelength extracted by the second monochromatic light extraction unit. A second optical fiber disposed so as to be incident from one end thereof, and a second lens for condensing the monochromatic light having the second wavelength emitted from the other end of the second optical fiber in the color mixing portion. Second color mixing means.
The light source may be common to the first monochromatic light extraction unit and the second monochromatic light extraction unit, or may be different light sources.

In the light emitting device having the above configuration, the monochromatic light having the first wavelength and the second wavelength set by the wavelength setting unit is extracted from the multicolor light emitted from the light source by the first monochromatic light extraction unit and the second monochromatic light extraction unit, respectively. Mix by color mixing means. At that time, the mixing ratio of each monochromatic light is adjusted by the mixing ratio adjusting means.
The chromaticity point of monochromatic light exists on the spectrum locus of the XY chromaticity diagram, and when the wavelength is changed by the wavelength setting means, the chromaticity point moves to an arbitrary position on the spectrum locus, so it is surrounded by a boundary line. All locations in the region can be included in the region connecting the chromaticity points.

The first monochromatic light taking-out means and the second monochromatic light extraction means as possible out to the monochromator.
The mixing ratio adjusting means may be a variable power source that adjusts the power supplied to the light source to increase or decrease the amount of light, or may be an attenuator that attenuates the first and second monochromatic lights individually.

  There are various types of light sources. In the wavelength range of 380 to 780 nm, there are light sources that emit multicolor light mainly having wavelength components in the wavelength range on the relatively short wavelength side, and on the relatively long wavelength side. There is also a light source that emits multicolor light mainly having wavelength components within a certain wavelength range. In addition, it is desirable from the viewpoint of improving the performance of the light emitting device that the monochromatic light extraction means such as a monochromator and the color mixing means such as a combination of an optical fiber and a lens are individually designed according to the target wavelength range.

Therefore, in the light emitting device of the present invention, the wavelength range of 380 to 780 nm is divided by a predetermined wavelength,
A first light source that emits a first multicolor light having all wavelength components in a wavelength range of at least 380 nm and less than the predetermined wavelength; and all wavelength components in a wavelength range of at least the predetermined wavelength and not more than 780 nm A second light source that emits a second multicolor light having
The wavelength setting means sets a first wavelength less than the predetermined wavelength and a second wavelength equal to or greater than the predetermined wavelength;
The first monochromatic light extraction means extracts the monochromatic light of the first wavelength from the first multicolor light, and the second monochromatic light extraction means extracts the monochromatic light of the second wavelength from the second multicolor light. Good.

By doing so, the portion relating to the first wavelength and the portion relating to the second wavelength in the light emitting device can be configured to be suitable for the respective wavelength ranges.
Further, if the predetermined wavelength is 520 nm, the chromaticity point corresponding to the monochromatic light of the predetermined wavelength is almost the apex of the spectrum locus, so when obtaining a desired color, the monochromatic light having a wavelength shorter than the predetermined wavelength is used. The choices of combinations of the respective wavelengths and light amounts of monochromatic light having a wavelength longer than the predetermined wavelength are increased.

  In the light emitting device, both the first wavelength and the second wavelength are set by the wavelength setting means, but one wavelength may be a fixed value.

That is, another aspect of the light emitting device of the present invention is:
A monochromatic light source emitting monochromatic light of a first wavelength of 380 nm or 780 nm;
A second light source that emits multicolor light having all wavelength components in a wavelength range including at least a wavelength other than the first wavelength in a wavelength range of 380 to 780 nm;
Wavelength setting means for setting a second wavelength that is different from the first wavelength;
A monochromatic light extraction means for extracting the monochromatic light of the second wavelength set by the said wavelength setting means from the multi color light,
Color mixing means for mixing the monochromatic light of the first wavelength and the monochromatic light of the second wavelength in a color mixing unit;
A mixing ratio adjusting means for adjusting a mixing ratio of the monochromatic light of the first wavelength and the monochromatic light of the second wavelength mixed by the color mixing means;
I have a,
The color mixing means has a first optical fiber arranged so that the monochromatic light of the first wavelength emitted from the monochromatic light source enters from one end thereof, and the first optical fiber emitted from the other end of the first optical fiber. The first color mixing unit including a first lens that collects monochromatic light of one wavelength in the color mixing unit and the monochromatic light of the second wavelength extracted by the monochromatic light extraction unit are incident from one end thereof. And a second color mixing unit comprising: a second optical fiber disposed in the second optical fiber; and a second lens that condenses the monochromatic light having the second wavelength emitted from the other end of the second optical fiber at the color mixing unit. It is characterized by that.

  Even in this case, all the locations in the area surrounded by the boundary line on the XY chromaticity diagram can be included in the area connecting the chromaticity points. Further, with such a configuration, it is not necessary to set the wavelength of the monochromatic light of the first wavelength, and it is only necessary to set the wavelength by the wavelength setting means for the monochromatic light of the second wavelength. This simplifies the manufacturing cost.

  According to the light emitting device of the present invention, since all colors in the region surrounded by the boundary line on the XY chromaticity diagram can be obtained, the color gamut is wider than the conventional light emitting device, and the display performance is improved. . In addition, the use of a light-emitting device increases because it is possible to reproduce a color close to monochromatic light that has been difficult to reproduce.

The figure explaining the color which can be reproduced when combining two light sources using an XY chromaticity diagram. The figure explaining the color which can be reproduced when combining three light sources using an XY chromaticity diagram. The figure which shows schematic structure of the light-emitting device of this invention. The figure explaining the 1st example of the operation | movement which obtains various colors using the light-emitting device of this invention. The figure explaining the 2nd example of the operation | movement which obtains various colors using the light-emitting device of this invention. The figure explaining the 3rd example of the operation | movement which obtains various colors using the light-emitting device of this invention. The figure which shows schematic structure of another aspect of the light-emitting device of this invention. FIG. 14 shows an example of a display using a light-emitting device of the present invention.

  Hereinafter, an embodiment of a light emitting device of the present invention will be described with reference to the accompanying drawings. FIG. 3 is a schematic configuration diagram of the light emitting device of the present invention.

  The light emitting device according to the present embodiment mainly includes a first wavelength monochromatic light extraction unit 10, a second wavelength monochromatic light extraction unit 20, and a color mixing unit 30. The first wavelength monochromatic light extraction unit 10 extracts the first wavelength monochromatic light (first monochromatic light) from the light source 11 and irradiates the color mixing unit 30, and the second wavelength monochromatic light extraction unit 20 receives the second wavelength monochromatic light from the light source 21. Monochromatic light (second monochromatic light) is taken out and applied to the color mixing unit 30.

The first wavelength monochromatic light extraction unit 10 includes a light source 11, a slit 12a, a mirror 13a, a wavelength dispersion element 14, a mirror 13b, a slit 12b, an optical fiber 15, a lens 16, a variable power source 17, a driving unit 18, and the like. Examples of wavelength dispersion elements include diffraction gratings and prisms. Here, a diffraction grating is used as the wavelength dispersion element 14. Further, the mirrors 13a and 13b and mirrors 23a and 23b described later can be omitted depending on the type of wavelength dispersion element used and the arrangement of the elements.

  As the light source 11, for example, a white light source such as a halogen lamp, an Xe lamp, or an LED can be used. The light source 11 is connected to a variable power source 17, and the variable power source 17 adjusts the light amount of the light source 11 by controlling the power supplied to the light source 11.

  The light emitted from the light source 11 passes through the slit 12a, is reflected by the mirror 13a, and then enters the diffraction grating 14. The diffraction grating 14 reflects only light having a specific first wavelength (first monochromatic light) toward the mirror 13b (spectral). The light is further reflected by the mirror 13b and then passes through the slit 12b.

The diffraction grating 14 can change the wavelength of the first monochromatic light reflected toward the mirror 13b by rotating. Driving means 18 is connected to the diffraction grating 14, and the diffraction grating 14 is rotated by the driving means 18. The driving means 18 is, for example, a stepping motor.
That is, each element between the slit 12a and the slit 12b constitutes a monochromator, so that the first monochromatic light is extracted from the light source 11.

  The first monochromatic light extracted from the light source 11 in this way is introduced into the inside from one end of the optical fiber 15. The first monochromatic light travels while repeating total reflection in the optical fiber 15 and is emitted toward the lens 16 from the other end of the optical fiber 15.

  The lens 16 is, for example, a convex lens, condenses the first monochromatic light by its condensing action, and irradiates it toward the color mixing unit 30 described later.

The second wavelength monochromatic light extraction unit 20 has the same configuration as that of the first wavelength monochromatic light extraction unit 10, and includes a light source 21, a slit 22a, a mirror 23a, a diffraction grating 24, a mirror 23b, a slit 22b, an optical fiber 25, and a lens 26. And a variable power source 27 and a driving means 28. Similarly to the light source 11, a halogen lamp or the like can be used for the light source 21.

The light source 21 is connected to a variable power source 27, and the variable power source 27 controls the power supplied to the light source 21 to adjust the light amount of the light source 21. Driving means 28 is connected to the diffraction grating 24, and the diffraction grating 24 is rotated by the driving means 28.

The variable power sources 17 and 27 and the drive units 18 and 28 can communicate with the PC control unit 40, respectively. By controlling the variable power supplies 17 and 27 by the PC control unit 40, the light amounts of the first monochromatic light and the second monochromatic light can be individually adjusted (that is, the mixing ratio). Further, by controlling the driving means 18 and 28 by the PC control unit 40, the wavelength of the first monochromatic light and the wavelength of the second monochromatic light can be individually adjusted.
Such a function of the PC control unit 40 can also be realized by firmware of the light emitting device.

The extracted second monochromatic light is applied to the color mixing unit 30 through the optical fiber 25 and the lens 26 in the same manner as the first monochromatic light. Similarly to the lens 16, the lens 26 may be a convex lens, for example. Note that the optical fiber 25 and the lens 26 may be omitted. Further, the optical fiber 15 and the lens 16 may not be provided in the first wavelength monochromatic light extraction unit 10.

  For example, a sheet for a projector screen is disposed in the color mixing unit 30. As a result, the first monochromatic light and the second monochromatic light emitted to the color mixing unit 30 are mixed to obtain mixed color light. That is, the optical fibers 15 and 25, the lenses 16 and 26, and the color mixing unit 30 serve as color mixing means for mixing the first monochromatic light and the second monochromatic light.

  Next, the operation for obtaining various colors by the light emitting device of this embodiment will be described with reference to FIG. In this embodiment, the first monochromatic light can be set in the wavelength range of 380 to 520 nm, and the second monochromatic light can be set in the wavelength range of 520 to 780 nm. In FIG. 4, A and B indicate chromaticity points of the first monochromatic light and the second monochromatic light, respectively.

For example, when the user sets the wavelength of the first monochromatic light to 380 nm and the wavelength of the second monochromatic light to 780 nm on the PC control unit 40, the PC control unit 40 sends a control signal to the driving unit 18 and the driving unit 28. . The driving means 18 rotates the diffraction grating 14 based on the sent control signal to set the wavelength of the first monochromatic light to 380 nm, and the driving means 28 turns the diffraction grating 24 based on the sent control signal. Thus, the wavelength of the second monochromatic light is set to 780 nm. As a result, the color obtained by mixing the first monochromatic light and the second monochromatic light is any color on a straight line connecting A (380 nm) and B (780 nm).

Further, when the user sets the light amounts (or their ratios) of the first monochromatic light and the second monochromatic light on the PC control unit 40, the PC control unit 40 sends control signals to the variable power source 17 and the variable power source 27. . The variable power source 17 controls the power supplied to the light source 11 based on the sent control signal, and the variable power source 27 controls the power supplied to the light source 21 based on the sent control signal. In this way, an arbitrary color on the straight line connecting A (380 nm) and B (780 nm) is obtained by changing the mixing ratio of the first monochromatic light and the second monochromatic light. If the mixing ratio of the first monochromatic light is increased, a color close to A on the straight line is obtained, and if the mixing ratio of the second monochromatic light is increased, a color close to B on the straight line is obtained. It is done.

Further, the user sets the wavelength of the first monochromatic light to (380 + Δλ1) nm and the wavelength of the second monochromatic light to (780−Δλ2) nm on the PC control unit 40 (or sets the values of Δλ1 and Δλ2). When set, the chromaticity points A and B move to the positions of (380 + Δλ1) nm and (780−Δλ2) nm, respectively. In this case as well, an arbitrary color on a straight line connecting both chromaticity points can be obtained by changing the light amounts of the first monochromatic light and the second monochromatic light as described above. In this way, a desired color on the XY chromaticity diagram is obtained by changing the wavelengths and light amounts of the first monochromatic light and the second monochromatic light.
Since the chromaticity point of monochromatic light having a wavelength of 520 nm is almost the apex of the spectrum locus, as in this embodiment, the wavelength of the first monochromatic light and the second monochromatic light are separated from each other at 520 nm. Thus, when obtaining a desired color, various combinations of the first monochromatic light and the second monochromatic light having a wavelength are possible.

The above-described Δλ1 and Δλ2 may be the same value (Δλ). That is, only by the user setting the value of Δλ on the PC control unit 40, the PC control unit 40 sets the wavelength of the first monochromatic light to (380 + Δλ) nm and the wavelength of the second monochromatic light to (780 A control signal is sent to the drive means 18 and the drive means 28 as Δλ ) nm. By doing so, the operation burden on the user can be reduced. In this case, as shown in FIG. 5, the chromaticity points A and B are located at (380 + Δλ) nm and (780−Δλ) nm, respectively, and an arbitrary color on a straight line connecting both chromaticity points is can get. As a wavelength range of the first monochromatic light and the second monochromatic light, for example, the first monochromatic light may be set to a wavelength range of 380 nm to 580 nm, and the second monochromatic light may be set to a wavelength range of 580 to 780 nm. 580 nm is an intermediate value between 380 nm and 780 nm.

  On the other hand, the wavelength of the first monochromatic light may be fixed at 380 nm. The user does not need to set the wavelength of the first monochromatic light on the PC control unit 40, and the operation burden is reduced. Further, the driving means 18 is not required, the configuration of the light emitting device is simplified, and the manufacturing cost can be reduced. In this case, as shown in FIG. 6, only the chromaticity point B moves on the spectrum locus. The wavelength of the second monochromatic light can be set in the wavelength range of 380 to 780 nm. The same effect can be obtained even if the wavelength of the first monochromatic light is fixed at 780 nm.

  As described above, since the light emitting device of the present invention can obtain all the colors on the XY chromaticity diagram, the color gamut is wider than that of the conventional light emitting device, and the display performance is improved. In particular, the use of a light emitting device increases by utilizing a color close to monochromatic light that has been difficult to reproduce until now.

In the above embodiment, the first wavelength monochromatic light extraction unit 10 and the second wavelength monochromatic light extraction unit 20 have different light sources. However, as shown in FIG. 7, a common light source may be used. In this case, the first wavelength monochromatic light extraction unit and the second wavelength monochromatic light extraction unit are arranged on both sides of the light source, and the slit 12a and the slit 22a of these extraction units are arranged coaxially. Moreover, by inserting each variable attenuator 19 and 29 between the slits 12b and the optical fiber 70 and the slit 22b and the optical fiber 71, the attenuation amount of the variable attenuator may be able to control the PC control unit 40. Thereby, it is possible to individually attenuate the light amounts of the first monochromatic light and the second monochromatic light and adjust the mixing ratio of the monochromatic lights. An ND filter or the like may be used to adjust the light amount.
With such a structure, the light-emitting device can be downsized and the manufacturing cost can be reduced.

  In addition, it can replace with the structure which takes out monochromatic light from a light source with a monochromator, and can also be set as the structure using the laser which emits monochromatic light. Even in this case, if the laser oscillation frequency can be set and the power supply can be controlled, the same effect as the light emitting device of the present application can be obtained.

  The above-described light emitting device obtains a desired color at one point (color mixing portion). If a plurality of light emitting devices are used, a display that can obtain a desired color at multiple points (each color mixing portion), etc. Display device.

  FIG. 8 is a drawing showing an example of a display using the light emitting device of the present invention. The display 50 has a plurality of pixels 60 (1, 1) to 60 (M, N) having M rows and N columns. On the back surface of the display, the light emitting device of the present invention is arranged corresponding to each pixel, and each pixel corresponds to a color mixing portion of each light emitting device.

The display 50 can display different colors for each pixel, and the colors can be selected from all the colors on the XY chromaticity diagram. Therefore, the display 50 has a wider color gamut and superior display performance.

DESCRIPTION OF SYMBOLS 10 ... 1st wavelength monochromatic light extraction part 11, 21 ... Light source 12a, 12b, 22a, 22b ... Slit 13a, 13b, 23a, 23b ... Mirror 14, 24 ... Diffraction gratings 15, 25, 70, 71 ... Optical fiber 16, 26 ... lenses 17, 27 ... variable power supply 18, 28 ... driving means 19, 29 ... variable attenuator 20 ... second wavelength monochromatic light extraction unit 30 ... color mixing unit 40 ... PC control unit 50 ... display 60 (1,1), 60 (M, 1), 60 (M, N) ... pixel

Claims (6)

Wavelength setting means for setting a first wavelength and a second wavelength that is different from the first wavelength;
First monochromatic light extraction means for extracting monochromatic light of the first wavelength from multicolor light emitted from a light source;
Second monochromatic light extraction means for extracting monochromatic light of the second wavelength from multicolor light emitted from a light source;
Color mixing means for mixing the monochromatic light of the first wavelength and the monochromatic light of the second wavelength in a color mixing unit;
A mixture ratio adjusting means for adjusting the mixing ratio of the monochromatic light of monochromatic light and the second wavelength of the first wavelength the color mixing means for mixing,
Have
The color mixing unit includes a first optical fiber disposed so that the monochromatic light having the first wavelength extracted by the first monochromatic light extraction unit is incident from one end thereof, and the other end of the first optical fiber. A first color mixing unit comprising a first lens for condensing the monochromatic light of the first wavelength emitted from the unit in the color mixing unit, and the monochromatic light of the second wavelength extracted by the second monochromatic light extraction unit. A second optical fiber disposed so as to be incident from one end thereof, and a second lens for condensing the monochromatic light having the second wavelength emitted from the other end of the second optical fiber in the color mixing portion. And a second color mixing unit . 2. The light emitting device according to claim 1, wherein the first monochromatic light extraction unit and the second monochromatic light extraction unit are monochromators. The wavelength range of 380 to 780 nm is divided by a predetermined wavelength,
The light source includes a first light source that emits first multicolor light having all wavelength components in a wavelength range of at least 380 nm and less than the predetermined wavelength, and all wavelength components in a wavelength range of at least the predetermined wavelength and not more than 780 nm A second light source that emits a second multicolor light having
The wavelength setting means sets a first wavelength less than the predetermined wavelength and a second wavelength equal to or greater than the predetermined wavelength;
The first monochromatic light extracting unit extracts the monochromatic light of the first wavelength from the first multicolored light, and the second monochromatic light extracting unit extracts the monochromatic light of the second wavelength from the second multicolored light. The light emitting device according to claim 1 or 2 . The light emitting device according to claim 3 , wherein the predetermined wavelength is 580 nm. A monochromatic light source emitting monochromatic light of a first wavelength of 380 nm or 780 nm;
A second light source that emits multicolor light having all wavelength components in a wavelength range including at least a wavelength other than the first wavelength in a wavelength range of 380 to 780 nm;
Wavelength setting means for setting a second wavelength that is different from the first wavelength;
A monochromatic light extraction means from the multi color light taking out monochromatic light of said second wavelength,
A mixture ratio adjusting means for adjusting the mixing ratio of the monochromatic light of monochromatic light and the second wavelength of the first wavelength,
Color mixing means for mixing the monochromatic light of the first wavelength and the monochromatic light of the second wavelength in a color mixing unit;
I have a,
The color mixing means has a first optical fiber arranged so that the monochromatic light of the first wavelength emitted from the monochromatic light source enters from one end thereof, and the first optical fiber emitted from the other end of the first optical fiber. The first color mixing unit including a first lens that collects monochromatic light of one wavelength in the color mixing unit and the monochromatic light of the second wavelength extracted by the monochromatic light extraction unit are incident from one end thereof. And a second color mixing unit comprising: a second optical fiber disposed in the second optical fiber; and a second lens that condenses the monochromatic light having the second wavelength emitted from the other end of the second optical fiber at the color mixing unit. A light emitting device characterized by that. Display device characterized by having a plurality of light-emitting device according to any one of claims 1-5.

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