JP2006196320A - Light source device and lighting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve irradiation efficiency, as well as restrain color shading, of a light source device with a lens and a lighting device equipped with the said light source device. <P>SOLUTION: The light source device 1 is provided with a light source part 2 irradiating light, a first transparent member 3 sealing the light source part 2, and a second member 4 formed on the first member 3 forming an interface with air and filling the role of a convex lens 5. An outer periphery 5c of the convex lens is formed further outside of a light axis A of the convex lens than a position P where an incident angle of the light irradiated from the light source part 2 toward an interface I2 forms a critical angle θc. With this structure, a ratio of light totally reflecting at the interface I2 is reduced to improve an irradiation efficiency of the light source device 1. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

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

  Examples of this type of conventional light source device are shown in FIGS. The light source device 101 includes a light source unit 102 that emits light, a transparent resin 103 that seals the light source unit 102, and lenses 105 a to 105 c installed on the transparent resin 103. The example shown in FIG. 8 shows the case where the Fresnel lens 105a is used as the lens, the example shown in FIG. 9 shows the case where the reflective lens 105b is used, and the example shown in FIG. 10 shows the case where the convex lens 105c is used. The example shown in FIG. 11 has an adapter 106 having a uniform thickness mixed with a pigment for converting the wavelength of light outside the convex lens 105c, and adjusts the light color emitted from the light source device 101. It is something that can be done.

  Further, by using a bulk type lens having a storage unit for storing the light source device and storing the light source device in the storage unit, the light emitted from the light source device can be collected without any modification to the light source device itself. It is also known that light can be emitted to obtain a desired illuminance (for example, see Patent Document 1).

JP 2002-221658 A

  However, in the case of the light source device 101 including the Fresnel lens 105a shown in FIG. 8, when the light source device 101 is used outdoors, water accumulates in the groove 150 of the Fresnel lens 105a and the lens effect is lost. there were.

  In the case of the light source device 101 including the reflective lens 105b shown in FIG. 9, if the refractive index of the member 104 forming the lens and the transparent resin 103 are close to each other, the light is not reflected at these interfaces Ia, so that the lens effect is obtained. There was a problem that it could not be obtained. In the figure, in order to explain the state in which the light is reflected by the reflective lens 105b, the left half of the transparent resin 103 of the light source device 101 is removed, and in this part, the light is transmitted between the member 104 and the air. Reflected at the interface.

  On the other hand, in the case of the light source device 101 having the convex lens 105c as shown in FIGS. 10 and 11, the above-described problem does not occur, but the light is reflected at the interface Ib that is substantially perpendicular to the optical axis A of the convex lens 105c. There has been a problem that since the ratio of the light reflected at the interface Ib is large, the emission efficiency is poor because sufficient studies have not been made on the light to be emitted. In particular, when the incident angle of the light emitted from the light source unit 102 with respect to the interface Ib is larger than the critical angle θc, the light is totally reflected and returns to the transparent resin 103 side. I was tied up. Furthermore, in the light source device 101 including the convex lens 105c, the light color varies depending on the light emission direction, and color unevenness may occur. However, the light source device including the adapter 106 having a uniform thickness as shown in FIG. In 101, the color unevenness could not be corrected sufficiently.

  Note that the bulk lens described in Patent Document 1 is used by being mounted on a light source device, and cannot improve the emission efficiency of the light source device itself or improve color unevenness.

  This invention is made | formed in view of this point, and it aims at improving a light emission efficiency, and providing the illuminating device provided with the light source device which can suppress a color nonuniformity, and this light source device. .

  In order to achieve the above object, the invention according to claim 1 is a light source unit that emits light, a transparent first member that seals the light source unit, and the air formed on the first member. And a second member that functions as a convex lens, and the interface between the second member and the air is relative to the first interface forming the convex lens and the optical axis of the convex lens. The second interface of the light emitted from the light source unit, the outer periphery of the convex lens including a second interface that is substantially perpendicular, the outer periphery of the convex lens being determined by the line of intersection of the first interface and the second interface The light source device is characterized in that the incident angle with respect to is formed outside the optical axis of the convex lens with respect to the position where the critical angle is formed.

  According to a second aspect of the present invention, in the light source device according to the first aspect, the light source unit emits light in a direction inclined with respect to the optical axis rather than light emitted in the direction of the optical axis of the convex lens. The second member that emits light so that the wavelength becomes longer and forms the convex lens contains a wavelength conversion material that shortens the wavelength of the light emitted from the light source unit, and the light of the convex lens The optical path in the direction inclined with respect to the optical axis is shorter than the optical path in the axial direction.

  According to a third aspect of the present invention, there is provided an illumination device comprising the light source device according to the first or second aspect.

  According to the first aspect, the outer periphery of the convex lens is formed outside the optical axis of the convex lens with respect to the position where the incident angle of the light emitted from the light source unit with respect to the second interface forms a critical angle. The ratio of light totally reflected at the second interface can be reduced, and the emission efficiency of the light source device can be improved.

  According to the second aspect, since the light having a short wavelength emitted from the light source unit in the direction of the optical axis of the convex lens passes through the second member through the long optical path, the wavelength conversion material included in the second member While the ratio of being converted to light having a long wavelength increases, light having a long wavelength emitted in a direction inclined with respect to the optical axis passes through the second member via a short optical path, so that the wavelength is not much. It does not change. For this reason, the difference in the color of the light emitted in the direction of the optical axis of the convex lens and the direction inclined with respect to the optical axis can be suppressed, and color unevenness can be suppressed.

  According to the third aspect, it is possible to obtain an illuminating device having high emission efficiency and little color unevenness.

  Hereinafter, a light source device according to a first embodiment of the present invention will be described with reference to FIGS. The light source device 1 is formed on the light source unit 2 that emits light, the transparent first member 3 that seals the light source unit 2, and the first member 3, and forms an interface with air, and is also a convex lens And a second member 4 serving as 5. For convenience of explanation, the convex lens 5 portion of the second member 4 is omitted in FIG. 1B, and only the convex lens 5 portion of the second member 4 is shown in FIG.

  For the light source unit 2, an LED (Light Emitting Diode) mounted on the substrate 20 is used. The emission color of the LED is not particularly limited, and LEDs having various emission colors can be used. The 1st member 3 and the 2nd member 4 are formed with the material which has translucency. A material having a refractive index equivalent to that of the second member 4 is used for the first member 3. For example, when acrylic resin (refractive index, about 1.4) is used as the second member 4, For the first member 3, a transparent silicone resin having a refractive index equivalent to that of the acrylic resin is used.

  The first member 3 seals the periphery of the light source unit 2 so that no air layer remains between the light source unit 2 and the second member 4. By sealing the periphery of the light source unit 2 so that no air layer remains in this way, it is possible to prevent the occurrence of malfunctions due to condensation or the like (for example, poor insulation or poor lens effect), which is also suitable for use outdoors. It becomes possible to do.

  The interface between the second member 4 and the air includes a first interface I1 that forms the convex lens 5, and a second interface I2 that is substantially perpendicular to the optical axis A of the convex lens, and the outer periphery 5c of the convex lens. Is determined by the line of intersection of the first interface I1 and the second interface I2.

  As the convex lens 5, for example, an axially symmetric lens as shown in FIG. 2 is used. In the present invention, since the convex lens 5 is used as a lens, water does not accumulate on the lens surface even when used upward outdoors, and the lens effect can be maintained.

  As shown in FIGS. 1A and 1B, the outer periphery 5c of the convex lens 5 is more convex than the position P at which the incident angle of the light emitted from the light source unit 2 with respect to the second interface I2 forms the critical angle θc. Are formed outside the optical axis A. Dc in FIG. 1B is an interval between two points on the same straight line passing through the optical axis A, and the incident angle forms the critical angle θc (that is, the right position P and the left position P in FIG. 1B). The convex lens 5 is formed so that the outer diameter D of the convex lens is larger than the distance Dc by disposing the outer periphery 5c of the convex lens at the position described above.

  As described above, according to the light source device 1 of the present embodiment, the outer periphery 5c of the convex lens is more than the position P at which the incident angle of the light emitted from the light source unit 2 with respect to the second interface I2 forms the critical angle θc. Since it is formed on the outer side with respect to the optical axis A of the convex lens, the ratio of light totally reflected at the second interface I2 can be reduced, and the emission efficiency of the light source device 1 can be improved.

  Next, a light source device according to a second embodiment of the present invention will be described with reference to FIGS. The light source device 1 according to the present embodiment is the first embodiment in that the first member 3 is provided with a protrusion 30 that protrudes toward the second member 4 and the thickness of the second member 4 is substantially uniform. Unlike the embodiment, other configurations are the same as those of the first embodiment.

  The second member 4 is formed so that the thickness t1 of the portion forming the first interface I1 is equal to the thickness t2 of the portion forming the second interface I2 (see FIG. 3A), or The thickness t1 of the portion forming the first interface I1 is formed to be slightly thicker than the thickness t2 of the portion forming the second interface I2 (see FIG. 3B). The first member 3 includes a projecting portion 30 projecting in a dome shape on the second member 4 side, so that an air layer does not remain between the light source portion 2 and the second member 4. The surroundings are sealed.

  According to the light source device 1 of the present embodiment, the same effects as those of the first embodiment can be obtained, and the thickness of the convex lens 5 is made substantially uniform, which is likely to occur when the thickness of the molded product is uneven. The occurrence of sink marks (dents generated on the outer surface of the molded product) can be prevented, and the moldability of the convex lens 5 can be improved. Moreover, the material of the second member 4 forming the convex lens 5 can be reduced.

  Next, a light source device according to a third embodiment of the present invention will be described. The light source device 1 according to the present embodiment is different from the first embodiment and the second embodiment described above in that color unevenness is suppressed. A light source unit 2 used in this embodiment is shown in FIG. 4, and a light source device 1 including the light source unit 2 shown in FIG. 5 is shown in FIG.

  The light source unit 2 includes an LED element 21 having a blue emission color, a substrate 22 having a recess 22a that houses the LED element 21, and a sealing member 23 made of a yellow phosphor that seals the recess 22a. Thus, the light emitted in the direction d2 inclined with respect to the optical axis emits light so that the wavelength is longer than the light emitted in the direction d1 of the optical axis of the convex lens. More specifically, the light emitted from the LED element 21 in the direction d1 of the optical axis of the convex lens passes through the sealing member 23 via a short optical path (optical path indicated by the length L1). The light emitted in the direction d2 tilted with respect to the optical axis passes through a long optical path (the optical path indicated by the length L2), whereas the white color is close to blue (light that includes a large amount of a blue component having a short wavelength). Since it passes through the sealing member 23, it becomes yellowish white (light containing a lot of yellow components having a long wavelength). Differences in the color of light emitted from the light source unit 2 in the directions d1 and d2 are offset by a second member 4 described later.

  As the second member 4, a member containing a wavelength conversion material that shortens the wavelength of the light emitted from the light source unit 2 is used. The wavelength conversion material is not particularly limited, and for example, a yellow pigment can be used. Further, as shown in FIG. 5, the second member 4 has an optical path in the direction d2 inclined with respect to the optical axis (the optical path indicated by the length L3) in the optical axis direction d1 of the convex lens (the optical path indicated by the length L3). The optical path indicated by the length L4 is shortened.

  Since white light (light containing a large amount of blue component with a short wavelength) emitted from the light source unit 2 in the direction d1 of the optical axis of the convex lens passes through the second member 4 through a long optical path, the second member While the ratio of being converted into light having a long wavelength by the wavelength conversion material included in 4 is high, white that is close to yellow emitted in the direction d2 inclined with respect to the optical axis (contains a lot of yellow components having a long wavelength) Light) passes through the second member 4 via a short optical path, so the wavelength does not change much.

  Thus, according to the light source device 1 of the present embodiment, the same effects as those of the first embodiment or the second embodiment can be obtained, and the optical axis direction d1 of the convex lens is inclined with respect to the optical axis. The difference in color of light emitted in the direction d2 can be suppressed, and color unevenness can be suppressed.

  FIG. 6 shows an example of a lighting device 10 that uses a plurality of light source devices 1 according to the first to third embodiments and is arranged in a matrix in the housing 10a. Such an illuminating device 10 can be used as a downlight, a ceiling light, a spotlight or the like with high emission efficiency and little color unevenness.

  The present invention is not limited to the configuration of the above embodiment, and various modifications can be made. For example, the convex lens 5 may have a semi-cylindrical shape as shown in FIG.

(A) is sectional drawing of the light source device which concerns on the 1st Embodiment of this invention, (b) is explanatory drawing of the outer periphery of the convex lens of the light source device. The perspective view of the same convex lens. (A), (b) is sectional drawing of the light source device which concerns on the 2nd Embodiment of this invention. Sectional drawing of the light source part of the light source device which concerns on the 3rd Embodiment of this invention. Sectional drawing of the light source device. The perspective view of the illuminating device provided with the light source device which concerns on this invention. The perspective view of the convex lens of the light source device which concerns on the modification of this invention. Sectional drawing of the light source device which concerns on a prior art example. Sectional drawing of the light source device which concerns on a prior art example. Sectional drawing of the light source device which concerns on a prior art example. Sectional drawing of the light source device which concerns on a prior art example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Light source device 2 Light source part 3 1st member 4 2nd member 5 Convex lens 5c The outer periphery of a convex lens 10 Illuminating device A Optical axis P of a convex lens P1 Position which forms a critical angle I1 1st interface I2 2nd interface θc Critical angle

Claims (3)

A light source unit that emits light, a transparent first member that seals the light source unit, and a second member that is formed on the first member and forms an interface with air and serves as a convex lens. And a member of
The interface between the second member and the air includes a first interface that forms the convex lens, and a second interface that is substantially perpendicular to the optical axis of the convex lens,
The outer periphery of the convex lens determined by the intersection line of the first interface and the second interface is more than the position where the incident angle of the light emitted from the light source unit with respect to the second interface forms a critical angle. A light source device formed outside the optical axis of the convex lens. The light source unit emits light so that the wavelength of the light emitted in a direction inclined with respect to the optical axis is longer than the light emitted in the direction of the optical axis of the convex lens,
The second member forming the convex lens contains a wavelength conversion material that shortens the wavelength of the light emitted from the light source unit, and is inclined with respect to the optical axis with respect to the optical path in the direction of the optical axis of the convex lens. The light source device according to claim 1, wherein a light path in a direction is short. An illumination device comprising the light source device according to claim 1.

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