WO2015064309A1

WO2015064309A1 - Light source and manufacturing method therefor

Info

Publication number: WO2015064309A1
Application number: PCT/JP2014/076695
Authority: WO
Inventors: 泰笹井
Original assignee: 岩崎電気株式会社
Priority date: 2013-10-28
Filing date: 2014-10-06
Publication date: 2015-05-07
Also published as: JP2015088254A; EP3065162A1; EP3065162A4

Abstract

This invention provides a light source, and a manufacturing method therefor, that is highly suitable for illuminating fresh food, said light source being capable of making the colors of meats, vegetables, and the like appear more vibrant than a high-color-saturation, high-color-rendering-index high-pressure sodium lamp does. Said light source is provided with a light-emitting unit that produces visible light rays, at least. If the wavelength region from 380 to 780 nm is divided into a blue/violet first wavelength region from 380 to 490 nm, a green second wavelength region from 490 to 570 nm, a yellow third wavelength region from 570 to 590 nm, and a red/orange fourth wavelength region from 590 to 780 nm, the light-emitting unit has an emission spectrum, with the ratio between the energy intensities of the light from the light-emitting unit integrated over the respective wavelength regions expressed as y1:y2:y3:y4 (with y1+y2+y3+y4 = 100), that satisfies the relations 7 ≤ y1 ≤ 11, 15 ≤ y2 ≤ 21, and 0 ≤ y3 < 3, with y4 constituting the remainder.

Description

Light source and manufacturing method thereof

The present invention relates to a light source and a manufacturing method thereof, and more particularly, to a super high saturation light source suitable for lighting fresh food and a manufacturing method thereof.

High-intensity discharge lamps (hereinafter referred to as HID lamps) are widely used because they are highly efficient and economical. HID lamps are roughly classified into three types, mercury lamps, metal halide lamps, and high-pressure sodium lamps, depending on the type of additive sealed in the arc tube. In general, high-pressure sodium lamps have a long life and high luminous efficiency, but high-saturation and color-rendering high-pressure sodium lamps are used as light sources for vivid colors such as meat vegetables, although their lifetime and luminous efficiency are inferior to ordinary high-pressure sodium lamps. Are known. In recent years, ceramic metal halide lamps using an arc tube made of ceramic (translucent alumina: PCA) instead of an arc tube made of quartz glass have been widely used. The lamp life and luminous efficiency are said to be superior to the lamp life and luminous efficiency of high chroma and color rendering high pressure sodium lamps.

However, high-saturation and color-rendering high-pressure sodium lamps are usually used for lighting fresh foods. In the case of a high saturation high color rendering high-pressure sodium lamp, the correlated color temperature is about 2500 K. However, in the case of a ceramic metal halide lamp, the correlated color temperature is relatively high, and it is difficult to achieve a relatively low correlated color temperature of about 2500 K. is there.

Japanese Unexamined Patent Publication No. 2004-288617 (Japanese Patent No. 4279122) discloses a ceramic metal halide lamp having a correlated color temperature of 2000 to 4500 K, Japanese Unexamined Patent Publication No. 2003-187744 and Japanese Unexamined Patent Publication No. 2009-520323. In ceramic metal halide lamps of 2500 to 4500 K, Japanese Patent Application Laid-Open Nos. 2007-53004 and 2011-154847, the color temperature is 2800 to 3700.
A ceramic metal halide lamp which becomes K is described. However, these patent documents do not disclose a specific technique for lowering the correlated color temperature to about 2500K, but also disclose a specific technique for making an object to be irradiated such as meat vegetables colorful. It has not been.

The wavelength spectrum distribution is also important as an illumination condition. In JP 2009-87602 A and JP 2012-113883 A, in order to perform efficient growth in a plant factory, in order to adjust the ratio of the energy intensity of the wavelength region of three colors to a predetermined value. It describes the setting of arc tube additives.
JP 2004-288617 A (Patent No. 4279122) Japanese Patent Laid-Open No. 2003-1877444 (Japanese Patent No. 4262968) JP 2009-520329 A JP 2007-53004 A JP 2011-154847 JP 2010-3488 JP 2009-87602 JP JP 2012-113883 A

As described above, the conventional technique has not yet established a technique for making an object to be irradiated such as meat vegetables vivid like a high-saturation and color-rendering high-pressure sodium lamp.

An object of the present invention is to provide a light source suitable for lighting fresh foods and a method for producing the same, which can show colors such as meat vegetables more vividly than a high-chroma and high color-rendering high-pressure sodium lamp.

According to an embodiment of the present invention, in a light source including a light emitting unit that generates at least visible light, the light emitting unit includes a wavelength region of 380 to 780 nm, a purple-blue first wavelength region of a wavelength of 380 to 490 nm, and a wavelength The four wavelength regions are divided into a green second wavelength region of 490 to 570 nm, a yellow third wavelength region of wavelength 570 to 590 nm, and an orange-red fourth wavelength region of wavelength 590 to 780 nm. When the ratio of the integrated values of the energy intensities of the light from the light emitting part calculated every time is y1: y2: y3: y4 (where y1 + y2 + y3 + y4 = 100), 7 ≦ y1 ≦ 11, 15 ≦ y2 ≦ 21, 0 ≦ y3 <3, y4 = the remaining emission spectrum.

According to the present embodiment, in the light source, the light emitting unit calculates a ratio of integrated values of energy intensity of light from the arc tube calculated for each of the four wavelength regions as y1: y2: y3: y4 (where y1 + y2 + y3 + y4 = 100). ) 8 ≦ y1 ≦ 9, 17 ≦ y2 ≦ 19, 0 ≦ y3 ≦ 2, and y4 = remaining emission spectrum.

According to this embodiment, in the light source, the light source is a high-intensity discharge lamp having an arc tube enclosing a rare gas and a luminescent material, and the emission spectrum of the light-emitting unit adjusts the composition and addition amount of the luminescent material. May be set by

According to an embodiment of the present invention, in a method for manufacturing a light source including a light emitting unit that generates at least visible light, a wavelength region of 380 to 780 nm, a violet-blue first wavelength region of a wavelength of 380 to 490 nm, and a wavelength of 490 to 490 A wavelength region dividing step of dividing into a second wavelength region of 570 nm green wavelength, a third wavelength region of yellow color having wavelengths of 570 to 590 nm, and a fourth wavelength region of orange red color having wavelengths of 590 to 780 nm; When the ratio of the integrated values of the light energy intensities calculated for each wavelength region is y1: y2: y3: y4 (where y1 + y2 + y3 + y4 = 100), 7 ≦ y1 ≦ 11, 15 ≦ y2 ≦ 21 and an emission spectrum setting step of setting an emission spectrum from the light emitting unit so that 0 ≦ y3 <3 and y4 = remainder.

According to this embodiment, in the light source manufacturing method, in the emission spectrum setting step, the ratio of the integrated values of the energy intensity of light from the arc tube calculated for each of the four wavelength regions is expressed as y1: y2: y3: y4. When (y1 + y2 + y3 + y4 = 100), the emission spectrum from the light emitting part may be set so that 8 ≦ y1 ≦ 9, 17 ≦ y2 ≦ 19, 0 ≦ y3 ≦ 2, and y4 = remainder.

According to the present embodiment, in the light source manufacturing method, the light source is a high-intensity discharge lamp having an arc tube enclosing a rare gas and a luminescent material, and in the emission spectrum setting step, the composition and addition amount of the luminescent material. The emission spectrum from the arc tube may be set by adjusting.

According to the present invention, it is possible to provide a light source suitable for lighting fresh food and a method for producing the same, which can show colors such as meat vegetables more vividly than a high-saturation, high color-rendering high-pressure sodium lamp.

FIG. 1 is a diagram illustrating an example of an arc tube of a ceramic metal halide lamp according to the present embodiment. FIG. 2 is a diagram illustrating an example of a ceramic metal halide lamp according to the present embodiment. FIG. 3 is a diagram illustrating an example of a ceramic metal halide lamp according to the present embodiment. FIG. 4 is a diagram showing examples of wavelength spectra of a high-pressure sodium lamp and a conventional ceramic metal halide lamp. FIG. 5 is a diagram illustrating an example of a wavelength spectrum of the ceramic metal halide lamp according to the present embodiment.

Hereinafter, embodiments of a light source and a method for manufacturing the same according to the present invention will be described in detail with reference to the accompanying drawings. In the drawings, the same elements are denoted by the same reference numerals, and redundant description is omitted.

Hereinafter, a ceramic metal halide lamp will be described as an example of a light source according to an embodiment of the present invention. However, the light source according to the embodiment of the present invention is not limited to a ceramic metal halide lamp, and other high-intensity discharge lamps. It may be a lighting device using other light sources such as LED lamps, LEDs, or electroluminescence (EL).

An example of an arc tube of a ceramic metal halide lamp according to the present invention will be described with reference to FIG. The arc tube 2 includes a light emitting unit 3 and

capillaries

4A and 4B extending at both ends thereof. The light emitting section 3 and the

capillaries

4A and 4B are formed by compressing and integrally forming a light transmitting ceramic powder such as alumina.

Electrode assemblies

6A and 6B are inserted through both ends of the

capillaries

4A and 4B, respectively. Both ends of the

capillaries

4A and 4B are hermetically sealed by frit glass having electrical insulation. Thereby, the

electrode assemblies

6A and 6B are fixed in place in the

capillaries

4A and 4B. The

electrodes

5A and 5B provided at the inner ends of the

electrode assemblies

6A and 6B are arranged at fixed positions in the light emitting unit 3. Power supply leads 7A and 7B protrude from both ends of the

capillaries

4A and 4B.

The inside of the light emitting unit 3 is filled with additives in addition to argon and mercury. Additives include luminescent materials such as alkali metal iodides, alkaline earth metal iodides, rare earth metal iodides, and the like. The additive sealed in the light emitting unit 3 will be described in detail later.

The effective length L and the effective inner diameter D are defined as the inner dimensions of the arc tube 2. The effective length L is the distance between both end faces in the case of a cylindrical arc tube, and in the arc tube in which the light emitting part and the capillary are continuously formed as shown in FIG. 1, light is emitted from the straight

tubular capillaries

4A and 4B. It is defined by the distance between the outer ends of the transition curved surfaces L1, L1 between the tubes 3. The effective inner diameter D is defined as the maximum inner diameter of the central portion between the

electrodes

5A and 5B in a light emitting tube other than a cylindrical shape. The effective length of the arc tube 2 is L, the effective inner diameter is D, and the ratio L / D between them is called the aspect ratio.

The temperature of each part of the light emitting unit 3 is determined by the wall load of the arc tube, the gas pressure in the translucent outer tube, the arc tube material, and the aspect ratio (L / D) of the arc tube, and particularly depends greatly on the wall load. The wall surface load is defined by a value obtained by dividing the lamp power by the total inner area of the light emitting unit 3. In the present embodiment, the light emitting unit 3 is designed so that the wall load is 20 to 30 W / cm ² (rated output 35 to 400 W). Thus, in this embodiment, the chemical reaction rate between the material constituting the inner wall surface of the light emitting part and the rare earth metal iodide can be kept low, and the life of the lamp can be extended.

An example of a ceramic metal halide lamp according to the present invention will be described with reference to FIG. The ceramic metal halide lamp 1 of the present example includes a light emitting tube 2, a cylindrical translucent sleeve 18 disposed so as to surround the light emitting portion 3, and an outer sphere 13 provided with a base 12 at one end. The structure of the arc tube 2 has been described with reference to FIG.

Two stems 15 and 16 are mounted on the stem 14 of the base 12. Two

support disks

17A and 17B are mounted on the support at predetermined intervals. A cylindrical translucent sleeve 18 is fixed to the

disks

17A and 17B. A getter 20 is mounted on the disk 17B. Power supply leads 7A and 7B protrude from both ends of the

capillaries

4A and 4B. The tips of the power supply leads 7A and 7B are welded to the

columns

15 and 16 directly or via

nickel wires

19A and 19B, respectively. Thus, the

electrodes

5A and 5B of the arc tube 2 are electrically connected to the base 12 via the power supply leads 7A and 7B and the

columns

15 and 16.

An example of a ceramic metal halide lamp according to the present invention will be described with reference to FIG. The ceramic metal halide lamp 1 of this example has an arc tube 2 and an outer bulb 13. The structure of the arc tube 2 has been described with reference to FIG. An outer sphere tip-off portion 13A is formed at one end of the outer sphere 13, and a pinch seal portion 13B is formed at the other end. A base 12 is attached to the end of the pinch seal portion 13B. External terminals 9 </ b> A and 9 </ b> B are attached to the base 12.

Two struts 15 and 16 are fixed to the pinch seal portion 13B. Power supply leads 7A and 7B protrude from both ends of the

capillaries

4A and 4B. The tips of the power supply leads 7A and 7B are welded to the

columns

15 and 16, respectively. A getter 20 is mounted on the column 15. The

support columns

15 and 16 are electrically connected to the

external terminals

9A and 9B via the metal foils 8A and 8B at the pinch seal portion 13B.

Thus, the

electrodes

5A and 5B of the arc tube 2 are electrically connected to the

external terminals

9A and 9B via the power supply leads 7A and 7B, the

support columns

15 and 16, and the metal foils 8A and 8B.

The ceramic metal halide lamp according to this embodiment may be a reflective ceramic metal halide lamp provided with a concave reflecting mirror in addition to the examples shown in FIGS.

The inventor of the present application examined the reason why high-saturation and high-color-rendering high-pressure sodium lamps were favorably used for lighting fresh foods. Various factors such as correlated color temperature CCT, color rendering index CRI, and wavelength spectrum distribution can be considered as the reason.

FIG. 4 shows an example of wavelength spectra of a high-saturation, high color rendering high-pressure sodium lamp (“high color rendering NH” in the figure) and a conventional ceramic metal halide lamp (“CMH (conventional example)” in the figure). The vertical axis represents specific energy [%], and the horizontal axis represents wavelength [nm]. The solid curve indicates the wavelength spectrum of a high-chroma and high color rendering high-pressure sodium lamp (NH), and the broken curve indicates the wavelength spectrum of a conventional ceramic metal halide lamp (CMH).

As shown in the figure, the conventional ceramic metal halide lamp has a peak near the wavelength of 600 nm representing orange, but the energy value of the red wavelength component having a wavelength of 630 nm or more is not large. Such a wavelength spectrum may not be suitable for fresh food lighting. On the other hand, in the case of a high saturation and high color rendering high-pressure sodium lamp, the energy value of the red wavelength component having a wavelength of 610 nm or more is large, but has a peak near the wavelength of 570 nm representing yellow, and further, the wavelength near 590 nm representing orange is missing. To do. Therefore, it is unlikely that the high-chroma and high-rendering high-pressure sodium lamp is suitable for lighting fresh foods such as meat vegetables that want to show vivid colors. However, as described above, in practice, high-saturation and color-rendering high-pressure sodium lamps are favorably used for lighting fresh food. The reason is not understood from the wavelength spectrum of the high-saturation, high color rendering high-pressure sodium lamp shown in FIG.

As a result of repeated trial and error, the inventors of the present application have made trial and error by referring to the wavelength spectrum of a high-saturation, high-color-rendering high-pressure sodium lamp. Was able to make a prototype.

Table 1 shows the color rendering index of the high saturation high color rendering high pressure sodium lamp (NH), the conventional ceramic metal halide lamp (CMH), and the prototype and comparative example ultra high saturation ceramic metal halide lamp (CMH) prepared by the inventors of the present application. The measurement results are shown. Since the prototype ceramic metal halide lamp (CMH) is an example of this embodiment, Table 1 shows the ceramic metal halide lamp (CMH) of this embodiment. A super high saturation ceramic metal halide lamp (CMH) as a comparative example is disclosed in Japanese Patent Application No. 2012-173201, which is filed by the same applicant as the present applicant.

The first column in Table 1 is the symbol of the color rendering index, the second column is the name of the color rendering index, the third column is the measurement result of the color rendering index of the high saturation high color rendering high pressure sodium lamp (NH), and the fourth column is conventional. The measurement results of the color rendering index of the ceramic metal halide lamp (CMH) of the present invention, the fifth column and the sixth column show the measurement result of the color rendering index of the ultra-high saturation ceramic metal halide lamp (CMH) according to the present embodiment and the comparative example.

The color rendering index represents the deviation from the color when viewed with the reference light defined by JIS. If the color rendering index is 100, this indicates a state where there is no deviation from the color when viewed with reference light. The closer the color rendering index is to 100, the smaller the color shift.

First, we compare the various color rendering indices of a conventional ceramic metal halide lamp and a high chroma and color rendering high pressure sodium lamp. In the case of a conventional ceramic metal halide lamp, the red color rendering index (R9) is almost the same as the high saturation high color rendering high pressure sodium lamp, but the other color rendering index is compared with the high saturation high color rendering high pressure sodium lamp. Then it is big enough.

Next, various color rendering indexes of the ceramic metal halide lamp according to the present embodiment and the comparative example and the high saturation high color rendering high pressure sodium lamp are compared. In the case of the ceramic metal halide lamp according to the present embodiment, the average color rendering index (Ra), the red color rendering index (R9), and the green color rendering index (R11) are equivalent when compared with a high-saturation high color rendering high-pressure sodium lamp. Very low. On the other hand, the yellow color rendering index (R10) and the blue color rendering index (R12) are considerably larger than those of the high-chroma and high-color-rendering high-pressure sodium lamp.

In the case of the ceramic metal halide lamp of the comparative example, the color rendering index (Ra), (R9), (R10), (R11), and (R12) are relatively high compared to the high chroma and color rendering high pressure sodium lamp. In particular, the yellow color rendering index (R10), the green color rendering index (R11), and the blue color rendering index (R12) are considerably larger than those of the high-saturation, high color rendering high-pressure sodium lamp.

From the above, the various color rendering index values and trends of the ceramic metal halide lamps according to the present embodiment and the comparative example are different from the various color rendering index values and trends of the high chroma and high color rendering high pressure sodium lamp. The ceramic metal halide lamp according to the present embodiment is suitable for lighting fresh food, and it has been found that the color of fresh food looks more vivid than the case of a high-chroma and high color rendering high-pressure sodium lamp. It is not clear even if various color rendering evaluation numbers are compared. The ceramic metal halide lamp according to the comparative example has been found to be suitable for lighting fresh food, but the reason is not clear even when various color rendering indexes are compared.

The inventor of the present application was able to complete the present invention by considering the following regarding the ceramic metal halide lamp according to the present embodiment and the comparative example.

FIG. 5 shows an example of the wavelength spectrum of the ceramic metal halide lamp according to the present embodiment and the comparative example. The vertical axis represents specific energy [%], and the horizontal axis represents wavelength [nm]. A solid curve indicates the wavelength spectrum of the ceramic metal halide lamp (CMH) according to the present embodiment, and a broken curve indicates the wavelength spectrum of the ceramic metal halide lamp (CMH) according to the comparative example.

As shown in the drawing, the ceramic metal halide lamp according to the present embodiment has a wavelength peak around a wavelength of 610 nm representing orange and 680 nm representing red. Furthermore, in the case of the ceramic metal halide lamp according to the present embodiment, there is no loss of wavelength in the vicinity of the wavelength of 590 nm representing yellow as in the case of the high chroma and color rendering high-pressure sodium lamp, but low energy at a wavelength of 560 to 600 nm representing yellow to orange. It becomes.

Therefore, the wavelength spectrum of the ceramic metal halide lamp according to the present embodiment is not similar to the wavelength spectrum of the high chroma and color rendering high-pressure sodium lamp shown in FIG. As described above, the ceramic metal halide lamp according to the present embodiment is suitable for fresh food lighting, and it has been found that the color of fresh food can be shown more vividly than in the case of a high saturation high color rendering high pressure sodium lamp. The reason is not necessarily clear from the wavelength spectrum of FIG.

In the case of the ceramic metal halide lamp according to the comparative example, there is no loss of the wavelength around 580 nm as in the case of the high chroma and color rendering high pressure sodium lamp. The ceramic metal halide lamp according to the comparative example has been found to be suitable for illumination of fresh food, but the reason is not known from the wavelength spectrum shown in FIG. Therefore, the inventors of the present application further analyzed the wavelength spectrum.

The inventor of the present application divides the wavelength region 380 to 780 nm of visible light into six wavelength regions, and the high saturation high color rendering high pressure sodium lamp (NH), the conventional ceramic metal halide lamp (CMH), this embodiment, and the comparative example. For a ceramic metal halide lamp (CMH), an integrated value (relative value) of energy intensity in each wavelength region was obtained. This is shown in Table 3. The integrated value of the energy intensity corresponds to the area below the waveform.

The first column of Table 2 is six wavelength regions, the second column is the color of each wavelength region, the third column is the upper and lower limits of the wavelength of each wavelength region, the fourth column is a high saturation high color rendering high pressure sodium lamp (NH) , The fifth column is the integrated value of the energy intensity of each wavelength region in the case of the conventional ceramic metal halide lamp (CMH), the sixth column and the seventh column are the present embodiment and The integrated value of the energy intensity of each wavelength region in the case of a ceramic metal halide lamp (CMH) according to a comparative example is shown. The integrated values in the fourth, fifth, sixth, and seventh columns are relative values.

The first wavelength region represents a violet system with a wavelength of 380 to 430 nm, the second wavelength region represents a blue system with a wavelength of 430 to 490 nm, the third wavelength region represents a green system with a wavelength of 490 to 570 nm, and the fourth wavelength region It represents a yellow system with a wavelength of 570 to 590 nm, the fifth wavelength region represents an orange system with a wavelength of 590 to 620 nm, and the sixth wavelength region represents a red system with a wavelength of 620 to 780 nm.

In Table 2, the ratio of the integrated value of energy intensity in the case of the conventional ceramic metal halide lamp is greatly different from the ratio of the integrated value of energy intensity in the case of the high saturation high color rendering high pressure sodium lamp. On the other hand, when the ratio of the integrated value of the energy intensity in the case of the ceramic metal halide lamp according to the present embodiment and the ratio of the integrated value of the energy intensity in the case of the high saturation high color rendering high-pressure sodium lamp are compared, The light emission ratio is small. That is, they do not match.

Comparing the ratio of the integrated value of the energy intensity in the case of the ceramic metal halide lamp according to the comparative example and the ratio of the integrated value of the energy intensity in the case of the high saturation and high color rendering high-pressure sodium lamp, in the case of the comparative example, the red emission ratio is There are few, and the orange light emission ratio is large. That is, they do not match.

Therefore, it can be explained from Table 2 why the illumination by the conventional ceramic metal halide lamp gives an impression different from the illumination by the high saturation high color rendering high pressure sodium lamp. On the other hand, the reason why the ceramic metal halide lamp according to the present embodiment and the comparative example is suitable for illumination of fresh food that wants to show colors such as meat vegetables vividly cannot be explained. In particular, the ceramic metal halide lamp according to the present embodiment is higher than the case of a high saturation high color rendering high pressure sodium lamp.
I can't explain why the color of fresh food can be shown vividly.

The inventor of the present application divides the wavelength region of visible light 380 to 780 nm into four wavelength regions, a high pressure sodium lamp (NH), a conventional ceramic metal halide lamp (CMH), a ceramic metal halide lamp according to this embodiment and a comparative example ( For CMH), the integrated value (relative value) of the energy intensity in each wavelength region was determined. This is shown in Table 3.

The first column of Table 3 is the number of the four wavelength regions, the second column is the color of each wavelength region, the third column is the upper and lower limits of the wavelength of each wavelength region, the fourth column is the high saturation high color rendering high pressure sodium lamp ( NH), the integrated value of the energy intensity in each wavelength region, the fifth column is the integrated value of the energy intensity of each wavelength region in the case of the conventional ceramic metal halide lamp (CMH), and the sixth and seventh columns are the present implementation. The integrated value of the energy intensity | strength of each wavelength range in the case of the ceramic metal halide lamp (CMH) by a form and a comparative example is shown. The integrated values in the fourth, fifth, sixth, and seventh columns are relative values.

The first wavelength region represents a violet-blue system with a wavelength of 380 to 490 nm, the second wavelength region represents a green system with a wavelength of 490 to 570 nm, the third wavelength region represents a yellow system with a wavelength of 570 to 590 nm, and the fourth wavelength region Represents an orange-red system having a wavelength of 590 to 780 nm.

In Table 3, the ratio of the integrated value of energy intensity in the case of the conventional ceramic metal halide lamp is greatly different from the ratio of the integrated value of energy intensity in the case of the high saturation high color rendering high pressure sodium lamp. When the ratio of the integrated value of the energy intensity in the case of the ceramic metal halide lamp according to the present embodiment and the ratio of the integrated value of the energy intensity in the case of the high saturation high color rendering high pressure sodium lamp are compared, The emission ratio is large, and the yellow emission ratio is extremely small. Therefore, they are different. Comparing the ratio of the integrated value of the energy intensity in the case of the ceramic metal halide lamp according to the comparative example and the ratio of the integrated value of the energy intensity in the case of the high saturation high color rendering high-pressure sodium lamp, in the case of the comparative example, the orange-red emission ratio However, the other light emission ratios are substantially the same.

Therefore, from Table 3, the reason why the illumination by the conventional ceramic metal halide lamp gives an impression different from the illumination by the high saturation and high color rendering high pressure sodium lamp can be explained. In addition, the reason why the ceramic metal halide lamp according to the comparative example is suitable for lighting fresh foods such as meat vegetables and the like that are vivid like the high saturation high color rendering high pressure sodium lamp can be explained. On the other hand, the ceramic metal halide lamp according to the present embodiment has been found to be able to show the color of meat vegetables and the like more vividly than the high saturation high color rendering high pressure sodium lamp, and the reason is the difference in the light emission ratio described above. I can guess.

Here, the ratio of the integrated values of the energy intensities in the four wavelength regions is expressed as y1: y2: y3: y4. However, y1 + y2 + y3 + y4 = 100. As shown in Table 3, in the ceramic metal halide lamp according to the present embodiment, the ratio of the integrated values of the energy intensities in the four wavelength regions is 9: 19: 2: 70.

Therefore, the inventor of the present application, as a condition for vividly showing the color of fresh food, in particular, the color of meat vegetables, is higher than the case of a high chroma and color rendering high-pressure sodium lamp. The tolerance range of the integrated value ratio was actually measured. In the ceramic metal halide lamp according to the present embodiment, the ratio of the integrated values of the energy intensity in the four wavelength regions was changed and used for lighting fresh foods such as vegetables, bread and meat, respectively. At the same time, a high saturation and high color rendering high pressure sodium lamp was used as standard illumination. The number of people who answered that the illumination by the ceramic metal halide lamp according to the present embodiment was “brighter” than the illumination by the high saturation high color rendering high pressure sodium lamp was counted. The respondents are 50 men and women between the ages of 18 and 64. As a result, the following knowledge was obtained.

When the ratio of the integrated values of energy intensity in the four wavelength regions is y1 = 7 to 11, y2 = 15 to 21, y3 = 0 to 3, and y4 = remainder, more than 90% of people have fresh food color I answered “brilliant”. When the ratio of the integrated values of energy intensity in the four wavelength regions is y1 = 8-9, y2 = 17-19, y3 = 0-2, y4 = remainder, 96% or more of people have fresh food color I answered “brilliant”. From this result, it is preferable that the emission ratio y1 in the violet-blue wavelength region is relatively large and the emission ratio y3 in the yellow wavelength region is relatively small as compared with the case of the high-saturation and color-rendering high-pressure sodium lamp. I understood. In the ceramic metal halide lamp used in the experiment, the emission ratio in the yellow wavelength region cannot be zero (y3 = 0). Accordingly, in the above-described experiment, the emission ratio of zero (y3 = 0) in the yellow wavelength region was realized by using the spectral transmission filter.

The following knowledge can be obtained from the analysis of the above wavelength spectrum. For the light source to be determined, the visible light wavelength region 380 to 780 nm is divided into four wavelength regions, and the ratio of the integrated values of the energy intensities in each wavelength region is obtained. When the ratio of the integrated values is y1 = 7 to 11, y2 = 15 to 21, y3 = 0 to 3, and y4 = remainder, the light source to be judged is a fresh one that wants to show the color of meat vegetables etc. vividly It is suitable for lighting of food, and it can be determined that the color of fresh food can be seen more vividly than in the case of a high chroma and color rendering high pressure sodium lamp. When the ratio of the integrated values is y1 = 8-9, y2 = 17-19, y3 = 0-2, y4 = remainder, the light source to be judged is fresh food that wants to show the color of meat vegetables etc. vividly It is suitable for lighting of food, and it can be accurately determined that the color of fresh food can be seen more vividly than in the case of a high-chroma and high-color-rendering high-pressure sodium lamp.

Here, the light source to be determined is not limited to a ceramic metal halide lamp. The light source to be determined may be another high-intensity discharge lamp, or an illumination device using another light source, for example, an LED lamp, an LED, or electroluminescence (EL).

Next, a method for actually realizing a light source suitable for lighting fresh food that wants to show colors such as meat vegetables vividly will be described. In general, in a high-intensity discharge lamp, the ratio of desired integrated values of the energy intensities in the four wavelength regions can be obtained by adjusting the type, composition, and addition amount of the luminescent material sealed in the arc tube.

In the light source using LED or electroluminescence (EL), the following method is used.

(1) LED light source with a single light emitting element A light emitting element emitting blue or ultraviolet light is molded with a resin mixed with a phosphor, or a relatively wide wavelength is mounted by mounting a cover mixed with a phosphor around the light emitting element. An area light source can be obtained. By adjusting the type, composition, and addition amount of the phosphor, it is possible to obtain a desired ratio of the integrated values of the energy intensities in the four wavelength regions.
(2) LED lamps that combine multiple light emitting elements or LED direct-attached lighting fixtures By combining multiple light emitting elements (such as red and blue) with different emission wavelengths (such as LEDs and EL), a light source with a relatively wide wavelength range is obtained. be able to. By selecting the wavelengths of the light emitting elements to be combined, it is possible to obtain a desired ratio of the integrated values of the energy intensities in the four wavelength regions. It is more preferable to provide a layer (such as a cover) that diffuses light outside the light-emitting portion, because color unevenness is less likely to be felt when the light source is viewed directly. In this case, the methods using the above-described phosphors may be combined.

Table 4 shows the composition of the arc tube additive of the ceramic metal halide lamp used in the experiment conducted by the inventors of the present application. The inventor of the present application uses the ceramic metal halide lamp according to the present embodiment for illumination of fresh food such as vegetables, bread, meat, etc., and the color of the fresh food is more brilliant than when using a high chroma and color rendering high pressure sodium lamp. "I counted the number of people who answered. Of the five ceramic metal halide lamps shown in Table 4, 90% of the respondents answered that the color of the fresh food was "brighter" when the ceramic metal halide lamp according to the present embodiment was used than when the high saturation high color rendering high pressure sodium lamp was used. That's it.

In Table 4, M (DyI ₃ ), M (TlI), M (NaI), M (CaI ₂ ), and M (LiI) are dysprosium iodide DyI ₃ , thallium iodide TlI, and calcium iodide, respectively. It represents the molar ratio (percentage) of CaI ₂ and lithium iodide LiI. In experiments conducted by the inventors of the present application, the arc tube additive contains thallium iodide TlI, calcium iodide CaI ₂ and lithium iodide LiI. Furthermore, dysprosium iodide DyI ₃ and sodium iodide NaI may be added as additives for the arc tube.

Sodium Na contributes to the orange system, calcium Ca contributes to the red system, and lithium Li contributes to the crimson system. By adding sodium iodide NaI, calcium iodide CaI ₂ and lithium iodide LiI in a predetermined molar ratio, a desired correlated color temperature can be obtained.

By adding dysprosium iodide DyI ₃ and thallium iodide TlI, the luminous efficiency increases, but the chromaticity deviation Duv increases. However, in this embodiment, by adding calcium iodide CaI _2, to suppress the increase of the chromaticity deviation Duv.

Table 5 shows the results of measuring the correlated color temperature CCT, chromaticity deviation Duv, average color rendering index Ra, red color rendering index R7, and luminous efficiency η for these five ceramic metal halide lamps. The correlated color temperature CCT was 2900 to 3100 K in all cases, and the chromaticity deviation Duv was 0 to -4 except for test number 5. The average color rendering index Ra, the red color rendering index R7, and the luminous efficiency η are not necessarily good. However, it has been found that these ceramic metal halide lamps are suitable for lighting fresh foods that want to show colors such as meat vegetables vividly. That is, in the prior art, a light source having a relatively low color rendering index and light emission efficiency was unlikely to be actually used. It was found for the first time that it is suitable for lighting fresh foods that want to show colors such as meat vegetables vividly.

The light source and the manufacturing method thereof according to the present invention have been described above, but these are examples and do not limit the scope of the present invention. Additions, deletions, changes, improvements, and the like that can be easily made by those skilled in the art with respect to the present embodiment are within the scope of the present invention. The technical scope of the present invention is defined by the appended claims.

DESCRIPTION OF SYMBOLS 1 ... Ceramic metal halide lamp, 2 ... Arc tube, 4A, 4B ... Capillary, 5A, 5B ... Electrode, 6A, 6B ... Electrode assembly, 7A, 7B ... Power supply lead, 8A, 8B ... Metal foil, 9A, 9B ... External Terminal: 12 ... Base, 13 ... Outer sphere, 14 ... Stem, 15, 16 ... Post, 17A, 17B ... Support disk, 18 ... Translucent sleeve, 19A, 19B ... Nickel wire, 20 ... Getter, 13A ... Outer sphere Chip-off part,
13B ... Pinch seal part

Claims

In a light source equipped with a light emitting unit that generates at least visible light,
The light emitting unit has a wavelength region of 380 to 780 nm, a purple-blue first wavelength region with a wavelength of 380 to 490 nm, a green second wavelength region with a wavelength of 490 to 570 nm, and a yellowish first wavelength region of a wavelength of 570 to 590 nm. The ratio of the integrated value of the energy intensity of the light from the light emitting part calculated for each of the four wavelength regions is divided into three wavelength regions and an orange-red fourth wavelength region having a wavelength of 590 to 780 nm. : Y3: y4 (provided that y1 + y2 + y3 + y4 = 100), 7 ≦ y1 ≦ 11, 15 ≦ y2 ≦ 21, 0 ≦ y3 <3, y4 = light source having an emission spectrum that becomes the remainder.
The light source according to claim 1.
When the ratio of the integrated value of the energy intensity of the light from the arc tube calculated for each of the four wavelength regions is y1: y2: y3: y4 (where y1 + y2 + y3 + y4 = 100), the light emitting unit 8 ≦ y1 ≦ 9, 17 ≦ y2 ≦ 19, 0 ≦ y3 ≦ 2, y4 = light source having an emission spectrum which is the remainder.
The light source according to claim 1 or 2,
The light source is a high-intensity discharge light source having an arc tube enclosing a rare gas and a luminescent material,
An emission spectrum of the light emitting unit is set by adjusting a composition and an addition amount of the light emitting substance.
In a method of manufacturing a light source including a light emitting unit that generates at least visible light,
A wavelength region of 380 to 780 nm, a purple-blue first wavelength region of a wavelength of 380 to 490 nm, a green second wavelength region of a wavelength of 490 to 570 nm, and a yellow third wavelength region of a wavelength of 570 to 590 nm; A wavelength region dividing step of dividing into an orange-red fourth wavelength region having a wavelength of 590 to 780 nm;
When the ratio of the integrated values of the energy intensities of light from the light emitting part calculated for each of the four wavelength regions is y1: y2: y3: y4 (where y1 + y2 + y3 + y4 = 100), 7 ≦ y1 ≦ 11, 15 ≦ an emission spectrum setting step for setting an emission spectrum from the light emitting unit such that y2 ≦ 21, 0 ≦ y3 <3, y4 = remainder,
A method of manufacturing a light source including:
In the manufacturing method of the light source of Claim 4,
In the emission spectrum setting step,
When the ratio of the integrated value of the energy intensity of light from the arc tube calculated for each of the four wavelength regions is y1: y2: y3: y4 (where y1 + y2 + y3 + y4 = 100), 8 ≦ y1 ≦ 9, 17 ≦ y2 A method of manufacturing a light source, wherein an emission spectrum from the light emitting unit is set so that ≦ 19, 0 ≦ y3 ≦ 2, and y4 = remainder.
In the manufacturing method of the light source of Claim 4 or 5,
The light source is a high-intensity discharge lamp having an arc tube enclosing a rare gas and a luminescent material,
In the emission spectrum setting step, an emission spectrum from the arc tube is set by adjusting a composition and an addition amount of the luminescent material.