JP2011154895A - Light source device and lighting system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To position a chromaticity coordinate plot of a mixed color light of a white light, from a white light source with a red light from a red light source on a black body radiation locus, and also when using the generally available, a general-purpose and low-cost white light source. <P>SOLUTION: A light source device includes the white light source 10, that radiates the white light positioned on the black body radiation locus; the red light source 20 radiating the red light to be mixed with the white light from the white light source 10; and a filter 30 for cutting of blue components, from the light from the white light source 10 at a predetermined rate, wherein the filter 30 has a transmittance of 20-60% in a wavelength range of 480 nm or less and a transmittance of 90% or higher, in a wavelength range of 500 nm or longer. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a light source device and an illumination device.

  Patent Document 1 discloses a general white light emitting device (white light source). FIG. 1 is a schematic view of a white light emitting device (white light source) disclosed in Patent Document 1. Referring to FIG. 1, a white light emitting device (white light source) 10 shown in Patent Document 1 is provided with a substrate 1, a blue light emitting element (for example, a blue LED) 2 provided on the substrate 1 and emitting blue light. And a molding material 3 formed on the blue light emitting element 2, and a yellow phosphor is dispersed in the molding material 3. Here, when a yellow phosphor having a predetermined concentration is dispersed in the molding material 3, the white light emitting device (white light source) 10 emits white light positioned on the black body radiation locus. N (generic) white light source.

  By the way, in order to improve the color rendering without reducing the luminous efficiency, a white light source (for example, a white LED) 10 and a red light source (for example, a red LED) 20 that emits red light are further prepared as shown in FIG. It is desired that the light source 10 and the red light source 20 emit light at the same time, and the light from the white light source 10 is mixed with red light.

  However, in this case, as a white light source (for example, a white LED) 10, when an ordinary general (general purpose) white light source that emits white light located on a black body radiation locus is used, as shown in FIG. The problem that the mixed color light of the light from the white light source 10 and the red light from the red light source 20 cannot be positioned on the black body radiation locus, and the color (white light) balance is lost (the color rendering property is greatly improved). There was a problem that could not be improved. FIG. 3 is a diagram showing chromaticity coordinates. In FIG. 3, C1 represents light from a normal (general purpose) white light source 10 that emits white light located on a black body radiation locus ( That is, chromaticity coordinate plot of white light located on a black body radiation locus, C2 is a chromaticity coordinate plot of red light from the red light source 20, and C3 normally emits white light located on the black body radiation locus. 2 is a chromaticity coordinate plot of mixed color light of the general (general purpose) white light source 10 and the red light from the red light source 20. As can be seen from FIG. 3, light (white light located on the black body radiation locus) and a red light from an ordinary general (general purpose) white light source 10 that emits white light located on the black body radiation locus. The chromaticity coordinate plot C3 of the mixed color light with the red light from the light source 20 moves toward the lower right direction (-duv) from the black body radiation locus, that is, toward the red region, and thus is positioned on the black body radiation locus. I can't let you.

JP 2007-126670 A

  In order to position the mixed light of the light from the white light source 10 and the red light from the red light source 20 on the black body radiation locus, the white light source 10 is located on the black body radiation locus as shown in FIG. A special white light source (for example, a white LED) using a molding material 93 in which a yellow phosphor is dispersed at a higher concentration than a normal (general purpose) white light source that emits white light, that is, normally It is also conceivable to use a special white light source that emits yellowish white light rather than the general (general purpose) white light source. In FIG. 4, the same reference numerals are given to the same parts as in FIG. 1.

  FIG. 5 is a diagram showing a direction in which the chromaticity coordinate plot C1 of the light from the white light source 10 changes in accordance with the ratio of blue to yellow, and as the yellow ratio increases, the chromaticity coordinate plot C1 is in the upper right direction. Move towards A.

  Therefore, a chromaticity coordinate plot of light (yellowish white light) from a special white light source using a molding material 93 in which a yellow phosphor as shown in FIG. 4 is dispersed at a high concentration is shown in FIG. As shown, the chromaticity coordinate plot C5 of the mixed color light of yellowish white light and red light is located on the black body radiation locus.

  However, in this case, a special white light source that emits yellowish white light is not a general (general-purpose) light source. Therefore, if this is used, the light source device and the illumination device are expensive. There was a problem of becoming. That is, a versatile and inexpensive white light source (for example, a white LED) is designed to target 6500K and 6000K on the black body radiation locus. Therefore, the white light source that emits yellowish white light as shown in FIG. 4 becomes a special white light source dedicated to simultaneously emitting light with the red light source, and is a general-purpose inexpensive white light source that is generally available ( For example, white LEDs) cannot be used, and there is a problem that the light source device and the illumination device become expensive.

  The present invention also provides a chromaticity coordinate plot of mixed color light of white light from a white light source and red light from a red light source, even when using a generally available and inexpensive white light source. An object of the present invention is to provide a light source device and an illuminating device that can be positioned on a locus.

  In order to achieve the above object, the invention described in claim 1 is a white light source that emits white light positioned on a black body radiation locus, and a red light that emits red light to be mixed with the light from the white light source. A light source and a filter that cuts a blue component from the light from the white light source at a predetermined ratio. The filter has a transmittance of 20 to 60% in a wavelength region of 480 nm or less, and 500 nm or more. The wavelength region of the light source device has a transmittance of 90% or more.

  According to a second aspect of the present invention, there is provided an illumination device characterized in that the light source device according to the first aspect is provided with an optical system.

  According to a third aspect of the present invention, in the illumination device according to the second aspect, the filter is provided between the white light source and the optical system.

  According to invention of Claim 1 thru | or 3, the white light source which radiate | emits the white light located on a black-body radiation locus | trajectory, and the red light source which radiate | emits the red light for mixing the light from the said white light source, A filter that cuts a blue component from the light from the white light source at a predetermined ratio, and the filter has a transmittance of 20 to 60% in a wavelength region of 480 nm or less, and a wavelength of 500 nm or more. Since the area has a transmittance of 90% or more, even when using a generally available inexpensive white light source that emits white light located on a black body radiation locus, The chromaticity coordinate plot of the mixed color light of the white light and the red light from the red light source is located on the black body radiation locus, and the color rendering can be greatly improved without reducing the light emission efficiency.

It is the schematic of the white light-emitting device (white light source) shown by patent document 1. FIG. It is a figure (schematic diagram) which shows a light source device which makes a white light source and a red light source emit light simultaneously, and mixes red light with the light from a white light source. It is a figure which shows the chromaticity coordinate plot in the light source device of FIG. It is a figure which shows the special white light source with which yellow fluorescent substance is disperse | distributed by high concentration. It is a figure which shows the direction from which the chromaticity coordinate plot of the light from a white light source changes according to the ratio of blue and yellow. It is a figure which shows the chromaticity coordinate plot at the time of using the special white light source of FIG. It is a figure (schematic diagram) which shows the example of composition of the light source device of the present invention, and an illuminating device. It is a figure which shows the emission spectrum distribution of the white light radiate | emitted from the general purpose white light source used in this invention. It is a figure which shows the emission spectrum distribution of the red light from a general purpose red light source. It is a figure which shows the emission spectrum distribution of mixed-color light when a general-purpose white light source and a general-purpose red light source are light-mixed light emission simultaneously. It is a figure which shows the spectral distribution characteristic (transmittance characteristic with respect to a wavelength) of the filter used for this invention. Emission spectrum before and after passing through a filter in which the wavelength region of 480 nm or less has a transmittance of 60% (that is, 40% cut) with respect to the emission spectrum of a general-purpose white light source (emission spectrum of FIG. 8) It is a figure which shows distribution. The wavelength region of 480 nm or less has a transmittance of 60% (that is, 40%) with respect to the emission spectrum of the mixed color light (emission spectrum in FIG. 10) when a general-purpose white light source and a red light source are simultaneously mixed color light emission. It is a figure which shows the emission spectrum distribution before and behind having passed the filter which is (cut). It is a figure which shows the chromaticity coordinate plot of the mixed-color light after allowing it to pass through a filter. It is a figure (schematic diagram) which shows the other structural example of the light source device of this invention, and an illuminating device. It is a figure (schematic diagram) which shows the other structural example of the light source device of this invention, and an illuminating device.

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

  FIG. 7 is a diagram (schematic diagram) showing a configuration example of the light source device and the illumination device of the present invention. In FIG. 7, the same parts as those in FIG. Referring to FIG. 7, the light source device includes a white light source (for example, a white LED) 10 and a red light source (for example, a red LED) 20 that emits red light to be mixed with the light from the white light source 10. Yes.

  Here, a general (general-purpose) inexpensive white light source (for example, a white LED) that emits white light positioned on a black body radiation locus is used as the white light source 10. That is, in the white light source (for example, white LED) 10 used in the present invention, the emission spectrum distribution of the white light emitted from the white light source 10 is as shown in FIG. 8, and the color temperature is 6000 to 6500K. To the extent, the chromaticity coordinate plot is located on the blackbody radiation locus. Specifically, FIG. 3 or FIG. 5 has the chromaticity coordinate plot C1 (that is, in this example, the color temperature is 6000 K and a general (general purpose) located on the black body radiation locus. An inexpensive white light source is used. Note that the color temperature of the white light source 10 (about 6000 to 6500 K) is higher by about 1500 to 2500 K than the color temperature of the mixed color light finally obtained (that is, the target) as described later. Yes.

  The red light source 20 is a general (general purpose) inexpensive red light source (for example, a red LED) that emits red light (red light having a wavelength range of 610 to 660 nm). FIG. 9 shows the emission spectrum distribution of red light from a general-purpose red light source (red light source that emits red light having an emission wavelength of 630 nm) 20.

  Also in the present invention, basically, white light from a white light source (for example, white LED) 10 and red light from a red light source (for example, red LED) 20 are mixed. Specifically, a white light source (for example, white LED) 10 and a red light source (for example, red LED) 20 are caused to emit mixed color light simultaneously. FIG. 10 shows the emission spectrum distribution of the mixed color light when the white light source (for example, white LED) 10 and the red light source (for example, red LED) 20 simultaneously emit mixed color light.

  However, in the present invention, a general (general purpose) inexpensive one that emits white light located on a black body radiation locus is used for the white light source (for example, white LED) 10, so that this alone is a color mixture. The chromaticity coordinate plot of light becomes the position of C3 as shown in FIG. 3, and is no longer positioned on the black body radiation locus.

  Therefore, in the present invention, as shown in FIG. 7, a filter (blue component cut filter) 30 that cuts the blue component from the light from the white light source 10 at a predetermined ratio is further provided. FIG. 11 is a diagram showing the spectral distribution characteristic (transmittance characteristic with respect to wavelength) of the filter 30. In FIG. Referring to FIG. 11, the filter 30 has a transmittance of 20 to 60% in the wavelength region of 480 nm or less (in other words, the wavelength region of 480 nm or less is cut in the range of 40 to 80%. The wavelength region of 500 nm or more has a transmittance of 90% or more. The filter 30 having such characteristics can be realized, for example, by dispersing a quinophthalone dye in a transparent acrylic resin and adding an ultraviolet absorber.

  In this way, a general-purpose white light source (for example, white LED) 10 and a red light source (for example, red LED) 20 having a wavelength of 610 to 660 nm are mixed and emitted at the same time, and a wavelength region of 480 nm or less is cut by 40 to 80% and 500 nm or more. Is passed through a filter 30 having a transmittance of 90% or more, so that white light from a general-purpose white light source (for example, white LED) 10 and a red light source (for example, red LED) 20 of 610 to 660 nm can be obtained. The brightness ratio of red light from the light source is in the range of 10: 1 to 18: 1 in terms of lumens (that is, when the wavelength region of 480 nm or less is cut by 40%, the brightness ratio of white light to red light) Is 18: 1 in terms of lumens, and when the wavelength region of 480 nm or less is cut by 80%, the brightness ratio between white light and red light is 10: 1 in terms of lumens, Ri is enhancing color rendering). Further, the filter 30 has the above characteristics, so that the chromaticity is hardly affected even when the emission peak of the emission spectrum fluctuates or the filter characteristics fluctuate.

  In FIG. 12, the wavelength region of 480 nm or less has a transmittance of 60% (ie, 40% cut) with respect to the emission spectrum of the general-purpose white light source (for example, white LED) 10 (emission spectrum of FIG. 8). The emission spectrum distribution before and after passing through the filter 30 is shown. In FIG. 12, S1 is the emission spectrum distribution before passing through the filter 30, and S2 is the emission spectrum distribution after passing through the filter 30. From FIG. 12, it can be seen that the emission spectrum distribution hardly changes except for the emission region related to the blue emission near 450 to 460 nm. Then, as shown in FIG. 14, the chromaticity coordinate plot C1 of the light from the general-purpose white light source (for example, white LED) 10 before passing through the filter 30 moves to C4 after passing through the filter 30. To do. This is the same as the position of the chromaticity coordinate plot when using a special white light source using a molding material 93 in which a yellow phosphor as shown in FIG. 4 is dispersed at a high concentration (see FIG. 6). In the present invention, it can be seen that the position of the chromaticity coordinate plot can be moved to C4 using a general-purpose white light source and the filter 30 without using a special white light source. That is, in FIG. 12, the emission spectrum in the vicinity of 450 to 460 nm decreases by 40% before and after passing through the filter 30, and therefore moves from C1 to C4 in the yellow region in the chromaticity coordinate plot diagram of FIG. It is possible to have the same effect as the phosphor concentration is increased.

  FIG. 13 shows an emission spectrum of mixed color light (a light emission in FIG. 10) when a general-purpose white light source (for example, white LED) 10 and a red light source (for example, red LED) 20 on a black body locus are simultaneously mixed color light emission. The spectrum distribution before and after passing through the filter 30 in which the wavelength region of 480 nm or less has a transmittance of 60% (that is, 40% cut) is shown. In FIG. 13, S3 is the emission spectrum distribution of the mixed-color light before passing through the filter 30, and S4 is the emission spectrum distribution of the mixed-color light after passing through the filter 30. Strictly speaking, the configuration of the apparatus and the lighting apparatus is not (in practice) the one shown in FIG. 7 but the case shown in FIG. Then, as shown in FIG. 14, the chromaticity coordinate plot of the mixed color light after passing through the filter 30 is C5, and white light from a general-purpose inexpensive white light source and red from a general-purpose inexpensive red light source. The chromaticity coordinate plot of the mixed light with the light can be positioned on the black body radiation locus (color temperature 4300K on the black body radiation locus) (a white light source (for example, white LED) having a color temperature 4300K on the black body radiation locus) )).

  As described above, in the light source device of FIG. 7, the white light source 10 that emits white light positioned on the black body radiation locus, the red light source 20 that emits red light to be mixed with the light from the white light source 10, And a filter 30 that cuts a blue component from the light from the white light source 10 at a predetermined ratio. The filter 30 has a transmittance of 20 to 60% in a wavelength region of 480 nm or less, and 500 nm or more. Since the wavelength region has a transmittance of 90% or more, this white light source can be used even when using a generally available and inexpensive white light source that emits white light located on a black body radiation locus. The color rendering property can be greatly improved without locating the chromaticity coordinate plot of the mixed light of the white light from the red light and the red light from the red light source on the black body radiation locus and without reducing the luminous efficiency.

  In the configuration example of FIG. 7, for example, a condensing lens 41 that condenses the light from the white light source 10 and a condensing lens 42 that condenses the light from the red light source 20 are provided as the optical system 40. Therefore, the lighting device can be configured. In the example of FIG. 7, the optical system 40 is the condensing lenses 41 and 42, but other lenses or the like may be used instead of the condensing lenses 41 and 42, or the condensing lens. In addition to 41 and 42, other lenses and the like may be further provided.

  Further, in the configuration example of FIG. 7, the filter (blue component cut filter) 30 is provided only for the white light source 10, but as shown in FIG. 15, for both the white light source 10 and the red light source 20. A filter (blue component cut filter) 30 may be provided, and in the case of the configuration example of FIG. 15, the same effect as that of the configuration example of FIG. 7 can be obtained.

  In the configuration example of FIG. 15, the optical system 40 further includes, for example, a condenser lens 41 that collects light from the white light source 10 and a condenser lens 42 that collects light from the red light source 20. By providing, it can be set as the structure of an illuminating device. In the example of FIG. 15, the optical system 40 is the condenser lenses 41 and 42, but other lenses or the like may be used instead of the condenser lenses 41 and 42, or the condenser lens In addition to 41 and 42, other lenses and the like may be further provided.

  7 and 15, the filter 30 is provided between the white light source (for example, white LED) 10, the red light source (for example, red LED) 20, and the optical system 40 (condensing lenses 41 and 42). However, as shown in FIG. 16, the optical system 40 (the condensing lenses 41 and 42) is opposite to the white light source (for example, white LED) 10 and the red light source (for example, red LED) 20 (that is, the optical system). 40 (outside of the condenser lenses 41 and 42) may be provided with a filter 30.

  In any of the configuration examples of FIGS. 7, 15, and 16, the provision of the filter 30 further provides the following advantages. That is, since the filter 30 has a yellow color tone due to the characteristic of cutting the blue region, when the yellow color filter 30 is not inserted, the white light source (for example, white LED) 10 that has been seen from the outside of the lens. The yellow phosphor used in the lens is enlarged by cutting the lens and looks unsightly like a fried egg. However, by arranging the filter 30 having the same yellow color tone on the white light source (for example, white LED) 10, a white light source ( For example, the white LED) 10 itself becomes inconspicuous, and it is possible to reduce the yellow phosphor from being magnified by a lens cut and having an unsightly appearance such as a fried egg.

  However, when the filter 30 is provided between the white light source 10 and the red light source 20 and the optical system 40 (condensing lenses 41 and 42) as in the configuration examples of FIGS. Compared with the case where the filter 30 is provided outside the system 40 (the condenser lenses 41 and 42), the following points are advantageous.

  That is, since the filter 30 has a yellow color tone due to the characteristic of cutting the blue region as described above, the white light source (for example, white LED) 10 and the red light source (for example, red LED) as shown in FIG. If the filter 30 is arranged at a position farthest from 20, it is not preferable from the viewpoint of appearance (yellow color tone is conspicuous and unpleasant for the viewer). On the other hand, as shown in FIGS. 7 and 15, when the filter 30 having a yellow color tone is disposed at a position closest to the LED, there is an advantage that the yellow color tone of the filter 30 becomes less conspicuous due to a lens cut effect. .

  The inventor of the present application actually lights up the general-purpose white LED 10 (color temperature is 6000 K) and the general-purpose red LED 20 (emission wavelength is 630 nm) on the black body locus in the configuration example of FIG. The mixed color light which passed the special filter 30 which cuts the following blue components 40% and passed the condensing lens etc. was investigated. As a result, this mixed color light has the same effect as when using a special white LED as shown in FIG. 4 in which the color temperature on the black body radiation locus is 4300 K and the yellow phosphor concentration is increased. It turns out that it is obtained. In other words, in order to obtain white light whose color temperature on the black body locus is 4300K, the black body locus is used without using a special white LED as shown in FIG. The above general-purpose white LED 10 (color temperature is 6000 K) can be used.

  The brightness ratio between the white light from the general-purpose white LED 10 and the red light from the red LED 20 is about 18: 1 in terms of lumens by passing the filter 30 that cuts 40% of the blue component of 480 nm or less. Thus, the average color rendering coefficient (Ra) representing color reproduction was improved from 75 to 85, and the special color rendering coefficient (R9) was greatly improved from -22 to 43. The luminous efficiency of the white LED 10 (color temperature is 6000 K) is 95 lumens / W, but the luminous efficiency of the mixed color light whose color temperature on the black body radiation locus is 4300 K is 91 lumens / W, Only about 4% light emission efficiency reduction. Generally in current LED lighting, such improvement of color rendering properties is mainly realized by a phosphor, but it has been found that the luminous efficiency is reduced by 20 to 30% by the method using the phosphor. Therefore, it was possible to actually show how excellent the method of improving the color rendering by maintaining the luminous efficiency by using the general-purpose LED of the present invention. Further, the cut rate of the blue component of 480 nm or less of the filter 30 is made larger than 40% (see FIG. 11), and the brightness ratio between the white light from the white LED 10 and the red light from the red LED 20 is changed from the red LED 20. Color rendering can be further improved by increasing the red light. Specifically, the cut rate of the blue component of 480 nm or less of the filter 30 is set to 80% (using the filter 30 that cuts 80% of the blue component of 480 nm or less), the white light from the white LED 10 and the red LED 20 By making the brightness ratio with red light 10: 1, the color rendering can be improved up to 95, and it can be used as food lighting or museum lighting sensitive to color reproduction according to the color rendering. It becomes like this.

  As described above, in the present invention, the general-purpose white light source (for example, white LED) 10 having a color temperature higher by 1500 to 2500 K than the color temperature (for example, 4300 K or 3000 K) on the target black body radiation locus and the emission wavelength. 610-660 nm red light source (for example, red LED) 20 is mixed color emission at the same time, cut the wavelength region of 480 nm or less by 40-80%, and the wavelength region of 500 nm or more has a transmittance of 90% or more. By passing through the filter 30, the light emission efficiency of mixed light of white light from a general-purpose white light source (for example, white LED) 10 and red light from a 610-660 nm red light source (for example, red LED) 20 is not reduced. In addition, the chromaticity coordinate plot of the mixed color light can be positioned on a black body radiation locus, and a general-purpose white light source (for example, a white LED) The brightness ratio between the white light from 0 and the red light from the red light source (for example, red LED) 20 of 610 to 660 nm can be in the range of 10: 1 to 18: 1 in terms of lumens. The color rendering coefficient Ra can be increased from 85 to 95, and the special color rendering coefficient R9 can be increased from 43 to 90, so that the color rendering can be improved.

The present invention can be used for general lighting such as food lighting and museum lighting, and a backlight for liquid crystal.

10 White light source (for example, white LED)
20 Red light source (eg red LED)
30 Filter 40 Optical system 41, 42 Condensing lens

Claims (3)

A white light source that emits white light located on a black body radiation locus, a red light source that emits red light to be mixed with the light from the white light source, and a predetermined ratio of a blue component from the light from the white light source The filter has a transmittance of 20 to 60% in a wavelength region of 480 nm or less, and a transmittance of 90% or more in a wavelength region of 500 nm or more. A light source device. An illuminating device, wherein the light source device according to claim 1 is provided with an optical system. The illumination device according to claim 2, wherein the filter is provided between the white light source and the optical system.

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