TWI396302B - A method of making white light source with high color rendering index and high color gamut - Google Patents

Description

一種製作高演色性及高色飽和度白光二極體光源之方法Method for producing high color rendering and high color saturation white light diode light source

本發明係一種製作高演色性及高色飽和度白光二極體光源之方法，尤指一種可被紫光(purple)發光二極體發出的光激發後產生純紅光的硒氧化鋅螢光粉，搭配純綠光晶片，以製作成高演色性及高色飽和度的白光光源。The invention relates to a method for producing a high color rendering and high color saturation white light diode light source, in particular to a selenium zinc oxide phosphor powder which can be purely red after being excited by light emitted by a purple light emitting diode. With a pure green light chip to produce a white light source with high color rendering and high color saturation.

自從1996年日本日亞化學公司發展出藍光發光二極體激發螢光粉使其產生黃光，再經光色混合，可產生高亮度之白光，至此開啟白光LED應用之時代。其利用藍光LED照射一螢光物質以產生與藍光互補之黃光，再利用透鏡原理將黃光、藍光予以混合，使人眼產生白光之視覺。Since 1996, Nichia Corporation of Japan has developed a blue light-emitting diode to excite fluorescent powder to produce yellow light, which is then mixed with light and color to produce high-brightness white light, thus turning on the era of white LED application. The utility model utilizes a blue LED to illuminate a fluorescent substance to generate yellow light complementary to the blue light, and then uses a lens principle to mix the yellow light and the blue light to make the human eye produce a white light vision.

白光乃為多顏色之混合光，可被人眼感覺為白光至少包含二種以上波長之混合光。例如人眼同時受紅、藍、綠光刺激時，或同時受到藍光與黃光刺激，或同時受到藍光與紅光刺激時均可感受為白光，故依此原理可設計出白光LED光源。White light is a mixed light of multiple colors, which can be perceived by the human eye as white light containing at least two types of mixed light. For example, when the human eye is stimulated by red, blue or green light at the same time, or stimulated by blue light and yellow light at the same time, or when it is stimulated by both blue light and red light, it can be perceived as white light. Therefore, a white light LED light source can be designed according to this principle.

習用之三波長型白光光源在製作時為了提高其演色性，皆使用三種或以上之螢光粉。但是欲同時利用多種螢光粉使其發出螢光，先決條件之一乃是所選用之激發光恰可被這些螢光粉所吸收，且各螢光體對此波長的光之吸收係數不能相差太多，連同光能轉換的量子效率也盡可能接近為佳，如此方可便於調配三原色螢光粉的比例以得到白光，因此造成選用螢光粉材料之困難。In order to improve the color rendering properties of the conventional three-wavelength white light source, three or more kinds of phosphor powders are used. However, one of the prerequisites for using a plurality of phosphor powders to emit fluorescence at the same time is that the selected excitation light can be absorbed by the phosphor powder, and the absorption coefficients of the light of the respective phosphors at this wavelength cannot be different. Too much, as well as the quantum efficiency of the light energy conversion is also as close as possible, so that it is convenient to mix the proportion of the three primary color phosphors to obtain white light, thus making it difficult to select the phosphor material.

而且每種螢光粉的比重、粒度大小、發光效率都不一致，混合不容易均勻，大量生產的產品其白光的色溫、演色性、色度座標都需要分類全檢，造成不良成本相當高，報廢品比例高。而且雙色光螢光粉的系統存在有內部彼此激發干擾的問題，使得發光效率較單一色光螢光粉系統為差。所以直到目前為止，主流白光發光二極體產品並不常見到採用兩種以上色光的螢光粉搭配晶片發光之組合。Moreover, the specific gravity, particle size and luminous efficiency of each type of phosphor powder are inconsistent, and the mixing is not easy to be uniform. The color temperature, color rendering and color coordinates of white light products need to be classified and fully inspected, resulting in a relatively high cost, and scrapped. The proportion of products is high. Moreover, the system of two-color light phosphors has a problem of internal excitation interference, which makes the luminous efficiency worse than that of the single color fluorescent powder system. So far, the mainstream white light emitting diode products are not common to the combination of two or more color fluorescent powders with wafer illumination.

在單一色光螢光粉系統中，目前主流為利用藍光晶片搭配黃光(YAG或TAG)螢光粉產生白光。然而，其缺點為色溫偏高，使得眼睛看久了會不舒服，且光譜內紅光部分太弱造成演色性偏低(70~80)及色彩飽和度差。In a single color luminescent phosphor system, the current mainstream is to use a blue light wafer with yellow (YAG or TAG) phosphor powder to produce white light. However, the disadvantage is that the color temperature is too high, which makes the eyes uncomfortable for a long time, and the red portion of the spectrum is too weak to cause low color rendering (70-80) and poor color saturation.

由於發光二極體正朝向液晶螢幕背光源以及照明領域發展，根據國際照明委員會(CIE)所訂出照明的標準，在室內照明光源的演色性要求為80~90，明顯地採用藍光晶片搭配黃光螢光粉的白光LED不適合作為室內照明使用。Since the light-emitting diode is moving toward the backlight of the liquid crystal screen and the development of the illumination field, according to the standard set by the International Commission on Illumination (CIE), the color rendering requirement of the indoor illumination source is 80-90, and the blue chip is obviously used with the yellow light. The white LED of the light powder is not suitable for use as indoor lighting.

另外，在液晶螢幕之背光源應用，要求色彩飽和度要高，針對紅光波長660nm、綠光波長525nm、藍光波長450nm這三原色的光強度之理想比例為1:1:1，才能配出各種各樣所需表現出的色彩，以提供觀賞者更逼眞更眞實地之色彩畫面。然而，藍光晶片搭配黃光螢光粉的白光LED，其藍光：綠光：紅光強度比值約為1:0.5:0.2，並不適合作為液晶電視螢幕的背光源使用。In addition, in the backlight application of the liquid crystal screen, the color saturation is required to be high, and the ideal ratio of the light intensity of the three primary colors of the red light wavelength of 660 nm, the green light wavelength of 525 nm, and the blue light wavelength of 450 nm is 1:1:1. A variety of colors are required to provide viewers with a more realistic and more realistic color picture. However, the blue light chip with the yellow light fluorescent white LED has a blue light: green light: red light intensity ratio of about 1:0.5:0.2, which is not suitable for use as a backlight for the LCD TV screen.

目前的液晶電視螢幕背光源所使用的白光LED，採用三個紅、綠、藍晶片的RGB LED為主流，然而LED的主要成本在於昂貴的晶片，晶片使用的數目越多，成本越高。而且紅光晶片的衰減速率比起藍光晶片和綠光晶片更快，導致溫度升高時，紅光偏弱，綠光和藍光偏強，使得螢幕的色彩飽和度變差，畫面表現會出現失眞的問題。The white LEDs used in current LCD TV backlights use three RGB LEDs of red, green and blue chips as the mainstream. However, the main cost of LEDs is expensive wafers. The more the wafers are used, the higher the cost. Moreover, the red wafer has a faster decay rate than the blue wafer and the green wafer, resulting in a weak red light, a strong green light and a blue light when the temperature rises, so that the color saturation of the screen is deteriorated, and the picture performance is lost. Awkward questions.

本發明之主要目的係使用一種可被紫光(purple)發光二極體發出的光激發後產生純紅光的硒氧化鋅螢光粉，搭配純綠光晶片，以製作成高演色性及高色飽和度的白光光源。The main object of the present invention is to use a selenium zinc oxide phosphor which can be excited by light emitted from a purple light-emitting diode to produce pure red light, and is matched with a pure green light wafer to produce high color rendering and high color. A white light source with saturation.

此發明之特徵係利用一種可被紫光(purple)發光二極體發出的光激發產生純紅光的硒氧化鋅螢光粉，搭配純綠光晶片，製作出演色性指數高於90，且紅光660nm、綠光525nm、藍光450nm強度比例接近均衡的高色飽和度白光光源。使用之紫光(purple)發光二極體，可採用位於色度座標(x0.26,y0.07)附近區域的發光色。使用之硒氧化鋅螢光粉，其原料為高純度之硒化鋅粉，以固態反應法在含有氧(Oxygen)的氣氛爐內燒成後急速冷卻而製成。使用之LED晶片係以半導體材料在晶圓上成長而成。塗佈係採用不會與螢光粉起反應的常溫固化膠，將之與適當量的螢光粉充份混合後進行。封裝之後，施以脈衝電流，即可獲得一高演色性及高色彩飽和度的白光光源。The invention is characterized in that a selenium zinc oxide phosphor which can be excited by a light emitted from a purple light-emitting diode to produce pure red light is used with a pure green light wafer to produce a color rendering index higher than 90 and red. The light intensity of 660 nm, green light 525 nm, and blue light 450 nm is close to the equilibrium high color saturation white light source. For the purple light-emitting diode to be used, an illuminating color in a region near the chromaticity coordinates (x0.26, y0.07) can be used. The selenium zinc oxide phosphor used is a high-purity zinc selenide powder which is prepared by solid-state reaction in a furnace containing oxygen (Oxygen) and then rapidly cooled. The LED chips used are grown on a wafer from semiconductor materials. The coating system is a room temperature curing gel which does not react with the phosphor powder, and is mixed with an appropriate amount of the phosphor powder. After the package, a pulsed current is applied to obtain a white light source with high color rendering and high color saturation.

使用高純度硒化鋅(ZnSe)粉末，利用固態反應法合成螢光粉，係在爐內含有氧(Oxygen)的氣氛下燒成之後急速冷卻，做成可被紫光(purple)發光二極體激發產生純紅光之硒氧化鋅螢光粉。The high-purity zinc selenide (ZnSe) powder is used to synthesize the phosphor powder by the solid state reaction method, and is rapidly cooled in an atmosphere containing oxygen (Oxygen) in the furnace to form a purple light-emitting diode. Excitation of pure red light selenium zinc oxide phosphor powder.

此白光光源所使用之紫光(purple)發光二極體，其發光光譜如第一圖所示。The purple light-emitting diode used in this white light source has an emission spectrum as shown in the first figure.

將純綠光晶片(或SMD LED)，固著在紫光(purple)SMD LED內部(或附近)。採用不會與硒氧化鋅螢光粉起反應的常溫固化膠(例如聚醋酸乙烯樹脂)，將之與適當量的螢光粉充份混合後，塗佈在紫光(purple)SMD LED表層，施以脈衝電流(1/10duty,900Hz)，即可獲得一高演色性及高色彩飽和度之白光光源。該封裝形式應以表面黏著封裝(surface mount device,SMD)方式進行，才能得到良好的發光效率。The pure green light wafer (or SMD LED) is affixed inside (or near) the purple SMD LED. A room temperature curing gel (for example, polyvinyl acetate resin) which does not react with the zinc selenide phosphor powder is mixed with an appropriate amount of the phosphor powder, and then coated on the surface of the purple SMD LED. With a pulse current (1/10 duty, 900 Hz), a white light source with high color rendering and high color saturation can be obtained. The package form should be performed in a surface mount device (SMD) mode to obtain good luminous efficiency.

製作好的白光發光二極體光源，其發光光譜如第二圖所示。A good white light emitting diode light source is produced, and its luminescence spectrum is as shown in the second figure.

是以，透過本發明之白光二極體光源之製作方法，具有如下述之特點：Therefore, the method for fabricating the white light diode light source of the present invention has the following characteristics:

(1)此發明所製作之白光光源，因為使用了純紅光的螢光粉，搭配紫光(purple)發光二極體內部的藍光460nm，以及發出純綠光525nm的晶片，所以能夠做出三原色有均衡發光強度的高色飽和度白光。(1) The white light source produced by the invention is capable of making three primary colors by using a pure red fluorescent powder, a blue light of 460 nm inside the purple light emitting diode, and a wafer emitting pure green light of 525 nm. High color saturation white light with balanced luminous intensity.

(2)此發明所製作之白光光源，因為是單一色光螢光粉系統，且並非連續寬廣的光譜，發光效率相當高，發出的白光強度良好。(2) The white light source produced by the invention is a single color light phosphor system, and is not a continuous broad spectrum, and the luminous efficiency is relatively high, and the emitted white light intensity is good.

(3)此發明所製作之白光光源，其所使用的硒氧化鋅螢光粉，製備流程極為簡單而製造成本低，量產的光譜準確性和再現性良好，適合於大量生產均一品質的高演色性及高色飽和度白光光源。(3) The white light source produced by the invention has a zinc selenide phosphor powder which is extremely simple in preparation process and low in manufacturing cost, and has good spectral accuracy and reproducibility in mass production, and is suitable for mass production of uniform quality. Color rendering and high color saturation white light source.

(4)此發明所製作之白光光源，其演色性高於80，符合於CIE的室內照明標準。又此白光光源是由接近純藍光、純紅光及純綠光的三原色混光而成，故色飽和度相當高，可符合於液晶電視背光源的要求。(4) The white light source produced by the invention has a color rendering property higher than 80 and conforms to the indoor lighting standard of CIE. The white light source is made up of three primary colors close to pure blue light, pure red light and pure green light, so the color saturation is quite high, which can meet the requirements of the LCD TV backlight.

綜上所述，本發明完全符合專利申請之要件，故爰依專利法提出申請，請詳查並請早日惠准專利，實感德便，以保障發明者之權益，若　鈞局之貴審查委員有任何的稽疑，請不吝來函指示。In summary, the present invention fully complies with the requirements of the patent application, so the application is filed in accordance with the Patent Law. Please check and request the patent as soon as possible, and feel the virtues to protect the rights and interests of the inventor. If you have any doubts, please do not hesitate to give us a letter.

惟，以上所述，僅為本發明最佳之一的具體實施例之說明與圖式，惟本發明之特徵並不侷限於此，並非用以限制本發明，本發明之所有範圍應以下述申請之專利範圍為準，凡合於本發明申請專利範圍之精神與其類似變化之實施例，皆應包含於本發明之範疇中，任何熟悉該項技藝者在本發明內，可輕易思及之變化或修飾皆可涵蓋在本案之專利範圍。However, the above description is only one of the preferred embodiments of the present invention, and the description of the present invention is not limited thereto, and is not intended to limit the present invention, and all the scope of the present invention should be as follows. The scope of the patent application is subject to the scope of the present invention, and any one skilled in the art can be easily considered in the present invention. Changes or modifications may be covered by the patent in this case.

圖一係此發明所使用的紫光(purple)發光二極體之發光光譜圖。Figure 1 is a luminescence spectrum of a purple light-emitting diode used in the present invention.

圖二係此發明所製作完成的高演色性及高色飽和度之白光光源之發光光譜圖。Figure 2 is a luminescence spectrum of a white light source with high color rendering and high color saturation produced by the invention.

Claims (4)

一種高演色性及高色彩飽和度白光二極體光源之製作方法；係利用至少包含鋅(Zn)、硒(Se)、氧(O)三種元素的紅光螢光粉塗佈在色度座標位於(x0.26,y0.07)附近區域發光色之紫光(purple)發光二極體上；搭配純綠光晶片；產生高演色性及高色飽和度的白光光源。 A method for fabricating a high color rendering and high color saturation white light diode light source; coating a chromaticity coordinate with a red fluorescent powder containing at least three elements of zinc (Zn), selenium (Se) and oxygen (O) It is located on the purple light-emitting diode of the illuminating color in the vicinity of (x0.26, y0.07); it is matched with a pure green light wafer; it produces a white light source with high color rendering and high color saturation. 如申請專利範圍第1項所述之製作方法；其中之硒氧化鋅螢光粉係使用高純度的硒化鋅粉以固態反應法在含有氧(Oxygen)的氣氛爐內燒成後急速冷卻而製成。 The production method according to claim 1, wherein the selenium zinc oxide phosphor powder is rapidly cooled by solid state reaction in a furnace containing oxygen (Oxygen) after being fired in a high-purity zinc selenide powder. production. 如申請專利範圍第1項所述之製作方法；其中之硒氧化鋅螢光粉係可被紫光(purple)發光二極體所發出的光激發後產生純紅光。 The method according to claim 1, wherein the selenium zinc oxide phosphor powder is excited by light emitted from a purple light-emitting diode to produce pure red light. 如申請專利範圍第1項所述之製作方法；其中之塗佈係採用不會與螢光粉起反應的常溫固化膠，將之與適當量的螢光粉充份混合後進行。The production method according to the first aspect of the invention, wherein the coating is carried out by using a room temperature curing gel which does not react with the fluorescent powder, and mixing it with an appropriate amount of the fluorescent powder.