JP5410335B2 - Light emitting device - Google Patents

Description

  The present invention relates to a light-emitting device that can be visually recognized by a color blind person.

  Compared with fluorescent lamps and incandescent lamps that have been used as light sources, LEDs have attracted attention as light sources because of their power saving and long life. Various indicators, illumination switches, backlight sources, illuminations, etc. It has come to be used in a wide range of fields such as light sources and decoration of amusement equipment.

  Such an LED (light emitting device) can emit light of a desired color such as blue, green, red, or white according to the application. In addition, a light emitting device capable of emitting a plurality of colors in one package is being developed.

  For example, a bullet-type LED lamp in which a chip base (bonding area) is provided at one end of a lead, a blue LED chip, a red LED chip, and a green LED chip are mounted on the chip base and each LED chip is protected with a transparent epoxy resin. It is disclosed (for example, see Patent Document 1).

JP-A-7-235624

  In the three-color LED lamp disclosed in Patent Document 1, various emission colors can be obtained by individually controlling the current flowing through each LED chip. A healthy person can recognize these various colors, but there are colors that are difficult or impossible for a color blind person to recognize.

  The majority of color blindness is the first color blindness (first color blindness) with a mutation in the gene for red vision substance or the second color blindness (second color blindness) with the mutation in the gene for green vision substance, Even if the function of either the red visual substance or the green visual substance is lost, a similar symptom that it is difficult to feel a color difference in the wavelength range of green to red is collectively called red-green color vision disorder.

  Red-green color vision impairment makes it difficult to distinguish colors with similar brightness in the green to red wavelength range (color identification of an object). In particular, in the wavelength range of light, the colors on the left and right (short wavelength side and long wavelength side) appear to be almost the same with the yellow to green wavelength range as the center, and "green and red" and "yellow green and yellow" It is difficult to distinguish and recognize the difference. For this reason, there has been a demand for a light emitting device that emits a color that can be recognized even by a color blind person.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a light-emitting device that can be recognized even by a color blind person.

The light emitting device according to the first invention, and amber light emitting element dominant wavelength emits orange light in the range of 600～615Nm, and blue-green light emitting element dominant wavelength emits blue-green light in the range of 500 - 510 nm, the orange light And a line segment connecting the orange light point and the blue-green light in the xy chromaticity diagram is a confusion color line connecting the red point and the green point. characterized Citea Rukoto so as not to be parallel.

The light emitting device according to the second invention, Oite the first shot Akira, further comprising a blue light-emitting element which emits blue light, the sealing unit is characterized in that are sealing the blue light-emitting element.

The light emitting device according to a third invention is characterized in that, in the second invention, the blue light emitting element has a dominant wavelength in a range of 455 to 475 nm.

  The first invention includes an orange light emitting element that emits orange light, a blue-green light emitting element that emits blue-green light, and a sealing portion that seals the orange light emitting element and the blue-green light emitting element. According to the specific visual sensitivity curve of the color blind person who has the first color blindness in which the gene of the red visual substance is mutated, it is orange (for example, wavelength of about 607 nm) compared to red (for example, wavelength of about 620 nm). In this case, the sensitivity is about 3 to 4 times better, so that a person with color blindness cannot easily recognize red or can easily recognize orange. By providing the orange light emitting element, the visibility can be improved as compared with the case of providing the red light emitting element.

  In addition, color blind persons who have a first color vision disorder with a mutation in the red vision substance gene or a second color vision disorder with a mutation in the gene for the green vision substance have confusion in which colors are difficult to distinguish. Color lines exist from green to red in the chromaticity diagram. By making the blue-green light emitting element and the orange light-emitting element into one package (sealed with a sealing portion), blue light can be emitted instead of green, and orange light can be emitted instead of red. Since the emitted light is not on the confusion line, it becomes easier for a color blind person to recognize.

The orange light emitting element has a dominant wavelength (corresponding to a single wavelength that humans feel when viewing with eyes) in the range of 600 to 615 nm, and the blue-green light emitting element has a dominant wavelength in the range of 500 to 510 nm. When the dominant wavelength is 600 to 615 nm, a color different from that of the conventional red light emitting element (620 nm) can be emitted. Further, when the dominant wavelength is 500 to 510 nm, it is possible to emit light having a color different from that of the conventional green light emitting element (520 nm). Accordingly, red light emission is avoided, and light emission color at a position away from the confusion color line existing from red to green in the chromaticity diagram is possible, which makes it easy for color blind persons to recognize.

In the second invention, a blue light emitting element that emits blue light is further provided, and the sealing portion seals the blue light emitting element. Thereby, in the chromaticity diagram, it is possible to emit any color inside the triangle connecting the three points of orange, blue-green, and blue. In this case, one side of the triangle is a straight line connecting orange and blue-green, and in the chromaticity diagram, the triangle is separated from the confusion line that approximates the straight line connecting red to green and has a different inclination (in parallel with the confusion color line). Therefore, it is possible to emit various colors that are easy to visually recognize for the visually impaired. In addition, since it is possible to emit orange light instead of red, it is easy for a color blind person to recognize.

In the third invention, the blue light emitting element has a dominant wavelength in the range of 455 to 475 nm. As a result, it is possible to emit various colors that are easily visible to the visually impaired.

  According to the first invention, by providing the orange light emitting element, the visibility can be improved as compared with the case of providing the red light emitting element. Further, blue light can be emitted instead of green, and orange light can be emitted instead of red, and the light emitted from the light emitting device is not confused, so that it is easy for a color blind person to recognize.

  According to the second aspect of the invention, it is possible to avoid red light emission, and to emit light at a position away from the confusion color line existing from red to green in the chromaticity diagram, which makes it easy for a color blind person to recognize.

  According to the third aspect of the present invention, it is possible to emit various colors that are easy to visually recognize for the visually impaired. In addition, since it is possible to emit orange light instead of red, it is easy for a color blind person to recognize.

  According to the fourth aspect of the present invention, it is possible to emit various colors that are easily visible to the visually impaired.

  According to the fifth aspect, by providing the orange light emitting element, the visibility can be improved as compared with the case of providing the red light emitting element.

  According to the sixth aspect of the invention, red light emission is avoided and it becomes easy for a color blind person to recognize.

It is a top view which shows an example of a structure of the light-emitting device which concerns on this Embodiment. It is the II-II sectional view taken on the line of FIG. It is explanatory drawing which shows an example of the confusion line of 1st color blindness (1st color blindness). It is explanatory drawing which shows an example of the confusion line of 2nd color blindness (2nd color blindness). It is explanatory drawing which shows an example of the luminescent color of the conventional light emitting diode. It is explanatory drawing which shows an example of the luminescent color of the light-emitting device of this Embodiment. It is explanatory drawing which shows the other example of the luminescent color of the light-emitting device of this Embodiment. 6 is a plan view illustrating an example of a configuration of a light-emitting device according to Embodiment 2. FIG. It is the IX-IX sectional view taken on the line of FIG. FIG. 10 is an explanatory diagram illustrating an example of a light emission color of the light emitting device according to the second embodiment. FIG. 10 is an explanatory diagram illustrating an example of a light emission color of a light emitting device according to a third embodiment. FIG. 10 is an explanatory diagram illustrating an example of a light emission color of a light emitting device according to a fourth embodiment.

Embodiment 1
Hereinafter, the present invention will be described with reference to the drawings illustrating embodiments thereof. FIG. 1 is a plan view showing an example of the configuration of the light emitting device 50 according to the present embodiment, and FIG. 2 is a cross-sectional view taken along the line II-II in FIG. The light emitting device 50 is, for example, a light emitting diode module. In FIG. 1, reference numeral 1 denotes a rectangular substrate made of ceramic or glass epoxy resin. On one side surface of the substrate 1, electrodes 11, 31, and 21 are provided to be connected to an external circuit at an appropriate distance. Electrodes 12, 32, and 22 are provided on the surface of the substrate 1 opposite to the above-described one side surface so as to correspond to the electrodes 11, 31, and 21, respectively. The electrodes 11 and 12, the electrodes 31 and 32, and the electrodes 21 and 22 form a pair, one side is applied with a predetermined voltage, and the other is connected to the ground level.

  Near the center of the substrate 1, an orange LED chip 10 as an orange light emitting element that emits orange light, a blue green LED chip 20 as a blue green light emitting element that emits blue green light, and a blue LED as a blue light emitting element that emits blue light. A chip 30 is mounted. The orange LED chip 10 is bonded to the electrodes 11 and 12 by a gold wire 13. The blue-green LED chip 20 is bonded to the electrodes 21 and 22 by a gold wire 23. The blue LED chip 30 is bonded to the electrodes 31 and 32 by a gold wire 33.

  The orange LED chip 10 has an AlIGaP-based compound semiconductor as a light-emitting layer, and has a dominant wavelength (corresponding to a single wavelength that humans feel when viewing with eyes) in the range of 600 nm to 615 nm, for example. The blue-green LED chip 20 has a GaN-based compound semiconductor as a light emitting layer, and has a dominant wavelength in the range of 500 nm to 510 nm, for example. The blue LED chip 30 has a GaN-based compound semiconductor as a light emitting layer, and has a dominant wavelength in the range of 455 nm to 475 nm, for example. The shape of the substrate 1 and the arrangement and number of LED chips on the substrate 1 are examples, and are not limited to the example of FIG.

  As shown in FIG. 2, a sealing portion 2 for sealing each LED chip is provided in a bowl shape on the upper outer periphery of the substrate 1. The inner side surface of the sealing part 2 forms a reflection part 3 that reflects light from each LED chip. The inside of the sealing portion 2 is filled with a light transmissive resin (for example, epoxy resin) 40 and the like, and the orange LED chip 10 and the blue-green LED chip 20 mounted on the substrate 1 by the light transmissive resin 40. The blue LED chip 30 is sealed.

  As the light-transmitting resin 40 for sealing, for example, an epoxy resin or a mixture of an epoxy resin and a silicone resin can be used. Further, the sealing resin may be liquid or powdered solid.

  In addition, since the orange LED chip 10, the blue-green LED chip 20, and the blue LED chip 30 are provided, the color temperature can be adjusted by adjusting the current flowing through each LED chip. In addition, by connecting an appropriate resistance element to each LED chip in series and packaging as a light emitting diode module, the current flowing through each LED chip can be set as appropriate, and a desired emission color can be obtained. it can.

  FIG. 3 is an explanatory diagram showing an example of the confusion line of the first color blindness (first color blindness), and FIG. 4 is an explanatory diagram showing an example of the confusion line of the second color blindness (second color blindness). The first color blindness (first color blindness) has a mutation in the gene for red vision material, and the second color blindness (second color blindness) has the mutation in the gene for green vision material. FIG. 3 is a plot of colors that the first color blind person feels the same color on the CIE 1931xy chromaticity diagram. FIG. 4 is a plot of colors that the second color blind person feels the same color on the CIE1931xy chromaticity diagram. What connected the plotted points is a confusing color line in which there are colors that appear to be confused with the same color by color blind people.

  As shown in FIGS. 3 and 4, many confusion color lines can be drawn on the xy chromaticity diagram. As can be seen from FIG. 3 and FIG. 4, the confusion color line exists almost parallel to the red and green axes and is distributed radially. As shown in FIG. 3, in the case of the first color blindness (first color blindness), there is a point where each confusion color line intersects near the red light, and as shown in FIG. In the case of the second color blind), the confusion color lines intersect at virtual points.

  FIG. 5 is an explanatory view showing an example of the light emission color of a conventional light emitting diode. As shown in FIG. 5, conventionally, there are light emitting diodes that can emit various single colors such as red, orange, yellow, green, white, blue-green, and blue. Among these, each light emitted from each of the red, orange, yellow, and green light emitting diodes is located on or near the confused color line in the xy chromaticity diagram. It was difficult to recognize different colors for the two color blind).

  FIG. 6 is an explanatory diagram showing an example of the emission color of the light emitting device 50 of the present embodiment. In FIG. 6, a range of triangles indicated by solid lines (triangles having points O, C, and B as vertices) indicates a range of colors that can be emitted by the light emitting device 50 of the present embodiment. As a comparative example, the range of triangles indicated by broken lines (triangles having points R, G, and B as vertices) is a range of colors that can be emitted by conventional three-color LEDs (red, green, and blue LED chips). Show. A conventional red LED has a wavelength of, for example, around 620 nm, a green LED has, for example, a wavelength of around 520 nm, and a blue LED has a wavelength of around 470 nm. FIG. 6 also shows a confusion color line in the case of the first color blindness (first color blindness).

  As shown in FIG. 6, in the case of the conventional three-color LED, a straight line RG connecting the red point R emitted from the red LED and the green point G emitted from the green LED exists substantially parallel to the confusion color line. For this reason, it is difficult for color blind people to distinguish and distinguish the light emitted from the red LED and the green LED.

  On the other hand, in the light emitting device 50 of the present embodiment, the orange point O emitted from the orange LED chip 10, the blue-green point C emitted from the blue-green LED chip 20, and the blue LED chip 30 are emitted in one package. A color within the range of a triangle having a blue point B as an apex is emitted. The straight line OC connecting the orange point O emitted from the orange LED chip 10 and the blue-green point C emitted from the blue-green LED chip 20 is not parallel to the confused color line and is away from the confused color line. Therefore, the color blind person can distinguish and recognize the orange color emitted from the orange LED chip 10 and the blue green color emitted from the blue-green LED chip 20. Moreover, since the color blind person can recognize the light emitted from the blue LED chip 30 without any problem, the orange point O emitted from the orange LED chip 10, the blue-green point C emitted from the blue-green LED chip 20, and the blue color. It is possible to recognize a color within a triangular range having a blue point B emitted from the LED chip 30 as a vertex.

  Thus, in the xy chromaticity diagram, the straight line connecting the red coordinate position and the green coordinate position is substantially parallel to the confusion color line of the first color blindness (first color blindness). Therefore, in the xy chromaticity diagram, the emission color of the LED chip is different from red and green so that the straight line connecting the coordinate positions indicating the emission colors of the two LED chips is not parallel to the confusion color line. Further, it is possible to obtain a luminescent color that can be recognized even by a color blind person.

  FIG. 7 is an explanatory diagram showing another example of the emission color of the light emitting device 50 of the present embodiment. FIG. 7 is different from FIG. 6 and shows the confusion color lines in the case of the second color blindness (second color blindness). In the case of FIG. 7, as in FIG. 6, the straight line OC connecting the orange point O emitted from the orange LED chip 10 and the blue-green point C emitted from the blue-green LED chip 20 is parallel to the confusion color line. In addition, since the light at a position away from the confusion color line is emitted, the color blind person can distinguish and recognize the orange color emitted from the orange LED chip 10 and the blue green color emitted from the blue-green LED chip 20. Moreover, since the color blind person can recognize the light emitted from the blue LED chip 30 without any problem, the orange point O emitted from the orange LED chip 10, the blue-green point C emitted from the blue-green LED chip 20, and the blue color. It is possible to recognize a color within a triangular range having a blue point B emitted from the LED chip 30 as a vertex.

  Thus, in the xy chromaticity diagram, the straight line connecting the red coordinate position and the green coordinate position is substantially parallel to the confusion color line of the second color blindness (second color blindness). Therefore, in the xy chromaticity diagram, the emission color of the LED chip is different from red and green so that the straight line connecting the coordinate positions indicating the emission colors of the two LED chips is not parallel to the confusion color line. Further, it is possible to obtain a luminescent color that can be recognized even by a color blind person.

  In addition, according to the specific visual sensitivity curve of the color blind person having the first color blindness in which the gene of the red vision substance is mutated, the color of orange (for example, about 607 nm) is higher than that of red (for example, wavelength of about 620 nm). In the case of (wavelength), the sensitivity is about 3 to 4 times better, so that a person with color blindness can easily recognize orange even when it is difficult or impossible to recognize red. By providing the orange LED chip 10, visibility can be improved as compared with the case of providing a red LED.

  The dominant wavelength of the red LED is in the range of 611 nm to 631 nm, and the general dominant wavelength is around 620 nm. Instead of red, the dominant wavelength of the orange LED chip 10 having an orange emission color different from red increases the sensitivity in the relative visibility curve of the color blind person having the first color blindness, and the light emission color close to red. Since it needs to be obtained, it is preferably in the range of 600 nm to 615 nm.

  The dominant wavelength of the green LED is in the range of 515 nm to 535 nm, and the general dominant wavelength is around 520 nm. The dominant wavelength of the blue-green LED chip 20 having a blue-green emission color different from green instead of green may be in the range of 495 nm to 510 nm. Furthermore, if the dominant wavelength of the blue-green LED chip 20 is in the range of 500 nm to 510 nm, the straight line connecting the orange coordinate position and the blue-green coordinate position in the xy chromaticity diagram is parallel to the confusion color line. And an emission color close to green can be obtained.

Embodiment 2
In the above-described first embodiment, the orange LED chip 10, the blue-green LED chip 20, and the blue LED chip 30 are mounted in one package. However, the present invention is not limited to this. The structure which mounts two types of LED chips may be sufficient.

  FIG. 8 is a plan view showing an example of the configuration of the light emitting device 60 of the second embodiment, and FIG. 9 is a sectional view taken along line IX-IX in FIG. As shown in FIG. 8, electrodes 11 and 21 for connecting to an external circuit are provided on one side surface of a rectangular substrate 1 made of ceramic, glass epoxy resin, or the like, separated by an appropriate length. Also, electrodes 12 and 22 are provided on the surface of the substrate 1 opposite to the one side surface, corresponding to the electrodes 11 and 21. Each of the electrodes 11 and 12 and the electrodes 21 and 22 forms a pair, a predetermined voltage is applied to one, and the other is connected to the ground level.

  Near the center of the substrate 1, an orange LED chip 10 as an orange light emitting element and a blue green LED chip 20 as a blue green light emitting element are mounted. The orange LED chip 10 is bonded to the electrodes 11 and 12 by a gold wire 13. The blue-green LED chip 20 is bonded to the electrodes 21 and 22 by a gold wire 23.

  The orange LED chip 10 has an AlIGaP compound semiconductor as a light emitting layer, and has a dominant wavelength in the range of 600 nm to 615 nm, for example. The blue-green LED chip 20 has a GaN-based compound semiconductor as a light emitting layer, and has a dominant wavelength in the range of 500 nm to 510 nm, for example.

  As shown in FIG. 9, a sealing portion 2 for sealing each LED chip is provided around the upper periphery of the substrate 1 in a bowl shape. The inner side surface of the sealing part 2 forms a reflection part 3 that reflects light from each LED chip. The inside of the sealing portion 2 is filled with a light transmissive resin (for example, epoxy resin) 40 and the like, and the orange LED chip 10 and the blue-green LED chip 20 mounted on the substrate 1 by the light transmissive resin 40. Is sealed.

  FIG. 10 is an explanatory diagram illustrating an example of the emission color of the light emitting device 60 according to the second embodiment. As shown in FIG. 10, by providing the orange LED chip 10 and the blue-green LED chip 20 in one package, an orange point O emitted from the orange LED chip 10 and a blue-green point emitted from the blue-green LED chip 20. The straight line OC connecting C is not parallel to the confused color line and emits light at a position away from the confused color line, so that the color blind person can detect the orange color emitted from the orange LED chip 10 and the blue-green LED chip 20. Can be distinguished and distinguished from the blue-green color emitted by.

  According to the specific visual sensitivity curve of the color blind person who has the first color blindness in which the gene of the red visual substance is mutated, it is orange (for example, wavelength of about 607 nm) compared to red (for example, wavelength of about 620 nm). In this case, the sensitivity is about 3 to 4 times better, so that a person with color blindness cannot easily recognize red or can easily recognize orange. By providing the orange LED chip 10, visibility can be improved as compared with the case of providing a red LED.

  In addition, color blind persons who have a first color vision disorder with a mutation in the red vision substance gene or a second color vision disorder with a mutation in the gene for the green vision substance have confusion in which colors are difficult to distinguish. Color lines exist from green to red in the chromaticity diagram. By making the orange LED chip 10 and the blue-green LED chip 20 into one package (sealed with a sealing portion), blue light can be emitted instead of green, and orange light can be emitted instead of red. Since the light radiated from 60 is not on the confusion line, the color difference is easily recognized by the color blind person.

Embodiment 3
In the second embodiment, the orange LED chip 10 and the blue-green LED chip 20 are sealed as one package. However, the present invention is not limited to this. For example, the orange LED chip 10 and the blue LED The chip 30 may be sealed as a single package.

  FIG. 11 is an explanatory diagram showing an example of the emission color of the light emitting device of the third embodiment. The light-emitting device of Embodiment 3 includes the orange LED chip 10 and the blue LED chip 30 in one package. According to the specific visual sensitivity curve of the color blind person who has the first color blindness in which the gene of the red visual substance is mutated, it is orange (for example, wavelength of about 607 nm) compared to red (for example, wavelength of about 620 nm). In this case, the sensitivity is about 3 to 4 times better, so that a person with color blindness cannot easily recognize red or can easily recognize orange. By providing the orange LED chip 10, visibility can be improved as compared with the case of providing a red LED.

  The orange LED chip 10 has a dominant wavelength in the range of 600 to 615 nm, and the blue LED chip 30 has a dominant wavelength in the range of 455 to 475 nm. When the dominant wavelength is 600 to 615 nm, a color different from that of the conventional red LED (620 nm) can be emitted. This avoids red light emission and makes it easier for color blind people to recognize.

Embodiment 4
In the fourth embodiment, the blue-green LED chip 20 and the blue LED chip 30 are sealed as one package. FIG. 12 is an explanatory diagram showing an example of the emission color of the light emitting device of the fourth embodiment. Compared to the case where a conventional blue LED and a green LED are combined, a beautiful light blue can be reproduced.

2 Sealing part (sealing part)
10 Orange LED chip 20 Blue green LED chip 30 Blue LED chip 40 Light transmissive resin (sealing part)

Claims (3)

An orange light emitting element that emits orange light having a dominant wavelength in the range of 600 to 615 nm ;
A blue-green light emitting element emitting blue-green light having a dominant wavelength in the range of 500 to 510 nm ;
A sealing portion for sealing the orange light emitting element and the blue green light emitting element ,
line segment connecting the points and blue-green light of the orange light in the xy chromaticity diagram, the light emitting device according to claim Citea Rukoto so as not to be parallel to the confusion color line connecting the red dot and green dot. A blue light emitting element that emits blue light;
The sealing part is
The light emitting device according to claim 1, wherein the blue light emitting element is sealed. The blue light emitting element is
The light emitting device according to claim 2 , wherein a dominant wavelength is in a range of 455 to 475 nm.

Images