JP2007034071A - Lighting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an illuminating device capable of easily realizing miniaturization and capable of irradiating illumination light with uniform illuminance without distortion.
Each lens portion 23b constituting a fly-eye lens 23 is formed in a planar circular shape. Thereby, the curvature of the entrance / exit surface of each lens part 23b can be set small, and the focal distance of each lens part 23b can be set short. Therefore, the fly-eye lens 23 can be thinned, and the lighting device 1 can be easily reduced in size. Moreover, by making each lens part 23b into a planar circular shape, the local distortion of the light beam 1 emitted from each lens part 23b can be accurately suppressed. Further, by shielding the area other than the lens portion 23b on the fly-eye lens 23 with the light shielding mask 24, unnecessary light 41 transmitted through the lens substrate 23a as it is is prevented from entering the irradiation area Al.
[Selection] Figure 2

Description

  The present invention relates to an illuminating device that irradiates light emitted from a light source with a uniform illuminance onto an irradiation surface using a fly-eye lens.

  Generally, when illuminating a specific irradiation area using an illumination device, it is desirable that the illuminance of the irradiation light be uniform within the irradiation area. For example, as disclosed in Patent Document 1, light from a light source is incident on a fly-eye lens in which a plurality of lens portions are arranged in a matrix, as described above. This is possible.

In this case, for example, as shown in FIG. 8, each lens unit 101 constituting the fly-eye lens 100 has a shape obtained by cutting out a part of a curved surface of a lens such as a spherical lens into a rectangle. In general, the lens units 101 are arranged without gaps.
JP 2001-337204 A

  However, as described above, in a configuration in which a part of a spherical lens or the like is used for each lens part of the fly-eye lens, the curvature of each lens part increases, and the focal distance d increases accordingly. Therefore, an illuminating device using this type of fly-eye lens is particularly limited in realizing downsizing in the optical axis direction.

  In addition, when each lens part is set to a rectangle, due to spherical aberration or the like due to the lens curved surface of each lens part, a phenomenon such as the four corners of the irradiation image being locally greatly distorted and extending outward, etc. May occur and may make the user feel uncomfortable.

  An object of the present invention is to provide an illuminating device that can be easily miniaturized and can irradiate illumination light having uniform illuminance without distortion.

  The present invention is a fly eye in which a light source and a plurality of lens parts having a planar circular shape are arranged on a lens substrate, and light from the light source is incident on each lens part and superimposed and emitted on a specific irradiation area. And a light-shielding unit configured to shield at least a region other than the lens portions on the lens substrate.

  According to the illuminating device of the present invention, it is possible to easily achieve downsizing and irradiate illumination light with uniform illuminance without distortion.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. 1 to 5 relate to a first embodiment of the present invention, FIG. 1 is a cross-sectional view of the main part of the lighting device, FIG. 2 is an exploded perspective view of the lighting device, and FIG. 3 (a) is a main part of the fly-eye lens. FIG. 3B is a cross-sectional view taken along the line II of FIG. 3A, FIG. 4 is an explanatory view showing the relationship between the light emitted from the fly-eye lens and the light shielding mask, and FIG. It is explanatory drawing which shows the relationship between an irradiation area | region and the irradiation area | region of each lens part.

  1 and 2, reference numeral 1 denotes an illuminating device. The illuminating device 1 includes, for example, a light source unit 10 that uses a surface-mounted light emitting diode (LED) 12 having a single-convex lens fixed to an emission plane 12a as a light source. The lens optical system unit 20 is provided on the light source unit 10.

  The light source unit 10 has an LED substrate 11. The LED substrate 11 holds the LED 12 by soldering or the like at a substantially central portion thereof, and further electrically connects the held LED 12 to a power supply circuit (not shown). Here, in order to improve the luminous efficiency of the LED 12, the radiation fins 13 are fixed to the back surface of the LED substrate 11.

  The lens optical system unit 20 includes a lens housing 21, a collimation lens 22 housed and held in the lens housing 21, and a fly-eye lens 23. Further, the lens optical system unit 20 has a light shielding mask 24 as a light shielding means facing the fly-eye lens 23 in the lens housing 21.

  As shown in FIG. 2, in the present embodiment, the lens housing 21 has a substantially rectangular tube shape, and an LED insertion port 30 is opened at one end in the optical axis direction. Further, at the other end of the lens housing 21 in the optical axis direction, an illumination light exit port 31 is opened at a position facing the LED insertion port 30. As shown in FIG. 1, when the lens housing 21 is crowned on the light source unit 10, the LED 12 is exposed to the inside through the LED insertion port 30, and the emission plane 12 a of the LED 12 is opposed to the emission port 31.

  The lens housing 21 has a lens insertion opening 33 that opens to one side, and collimation lens holding grooves that face each other in order from the LED insertion opening 30 side on the inner surface of each side wall adjacent to the lens insertion opening 33. 35, a fly-eye lens holding groove 36, and a light shielding mask holding groove 37.

  Here, reference numeral 45 in FIG. 2 denotes a side plate. The side plate 45 is formed by attaching the lenses 22 and 23 and the light shielding mask 24 in the lens housing 21 and then sticking them with an adhesive tape or the like, for example. The lens insertion port 33 is closed.

  The collimation lens 22 is, for example, a lens member in which a lens portion 22b is integrally formed on the exit side of a substantially rectangular planar lens substrate 22a inserted and held in the collimation lens holding groove 35. Then, the collimation lens 22 converts the light incident from the LED 12 into substantially parallel light by the lens portion 22b and emits it.

  The fly-eye lens 23 includes, for example, a plurality (for example, an incident surface projecting downward and an exit surface projecting upward on a substantially rectangular lens substrate 23a inserted and held in the fly-eye lens holding groove 36. For example, a lens member in which 5 × 7 lens portions 23b are integrally formed in a matrix. Here, as shown in FIG. 3, in the present embodiment, each lens portion 23 b is configured by, for example, a lens portion having a planar circular shape in which the entrance surface and the exit surface are each formed in a hemispherical shape, and the edges of each other. The parts are arranged on the lens substrate 23a so as to circumscribe the part. And each lens part 23b mutually superimposes the light which each injects from the collimation lens 22 on the preset irradiation area | region Al. That is, as shown in FIG. 5, in the present embodiment, the irradiation area Al of the fly-eye lens 23 is set to be circular, and each lens unit 23 b includes light incident from the collimation lens 22 and includes the irradiation area Al. Each is converted into a circular light beam l and emitted.

  The light shielding mask 24 includes, for example, a light-transmitting substrate 24a having a substantially rectangular shape inserted and held in the light-shielding mask holding groove 37, and a light-shielding portion (light-shielding film) 24b formed on the light-transmitting substrate 24a. In the present embodiment, the light shielding mask 24 faces the light exit surface of the fly-eye lens 23 in close proximity, and the light shielding portion 24b has a light transmitting portion at a position corresponding to each lens portion 23b of the fly-eye lens 23. 24c is open. The light-shielding mask 24 shields light at least from the areas other than the lens portions 23b.

  More specifically, each light transmitting portion 24c is configured by a circular hole portion that allows passage of only a light beam formed when parallel light enters each lens portion 23b of the fly-eye lens 23. Thereby, as shown in FIG. 4, the light shielding mask 24 shields the light 41 transmitted through the gaps between the lens portions 23b. In addition, for example, a part of the light 42 incident at a predetermined angle with respect to the lens unit 23b, in other words, a part of the behavior that deviates from the optical path defined by the lens unit 23b with respect to the parallel light. The light 42 is also shielded. Note that the cross section of the fly-eye lens 23 shown in FIG. 4 is a cross section along the diagonal direction of the lens portions 23b arranged in a matrix (that is, a cross section taken along the line III-III in FIG. 3).

  According to such an embodiment, each lens portion 23b constituting the fly-eye lens 23 is formed in a planar circular shape, so that, for example, a hemispherical lens curved surface or the like is used as it is on the entrance / exit surface of each lens portion 23b. be able to. Thereby, the curvature of the entrance / exit surface of each lens part 23b can be set small, and the focal distance d of each lens part 23b can be set short. Therefore, the fly-eye lens 23 can be thinned, and the lighting device 1 can be easily reduced in size.

  Moreover, by making each lens part 23b into a planar circular shape, the local distortion of the light beam 1 emitted from each lens part 23b can be accurately suppressed, and an irradiation image without distortion is irradiated onto the irradiation surface. can do.

  At this time, in the fly-eye lens 23, a gap is formed between the lens portions 23b. However, the region other than the lens portion 23b is shielded by the light shielding mask 24, so that it is unnecessary to transmit the lens substrate 23a as it is. It is possible to prevent the light 41 from entering the irradiation area Al and to irradiate illumination light with high uniformity.

  In this case, in particular, by disposing the light-shielding mask 24 on the exit side of the fly-eye lens 23, it is possible to shield part of unnecessary light 42 incident at a predetermined angle with respect to the lens portion 23b. It is possible to improve the uniformity in the irradiation region Al.

  In the above-described embodiment, an example in which the light shielding mask 24 is disposed on the exit side of the fly-eye lens 23 has been described. However, the light shielding mask 24 may be disposed on the incident side of the fly-eye lens 23. Of course, it may be arranged on the incident side and the emission side of the fly-eye lens 23.

  Next, FIGS. 6 and 7 relate to the second embodiment of the present invention, FIG. 6 is an exploded perspective view of the illumination device, and FIG. 7 is an explanatory view showing light emitted from the fly-eye lens. Note that this embodiment is different from the above-described first embodiment in that a fine uneven process is performed on the lens substrate 23a of the fly-eye lens 23 in place of the light shielding mask 24. In addition, about the same structure, a same sign is attached | subjected and description is abbreviate | omitted.

  That is, as shown in FIG. 6, in the present embodiment, the lens substrate 23a of the fly-eye lens 23 has a fine uneven surface 23c by, for example, sandblasting on the exit side surface excluding each lens portion 23b. Is formed. The fly-eye lens 23 diffuses, scatters, or the like the light transmitted through the region on the lens substrate 23a other than the lens portion 23b by the uneven surface 23c. Of the light that passes through the lens substrate 23a without passing through the lens portion 23b, for example, light that is irregularly reflected or scattered as indicated by the dashed arrows in FIG. Becomes an invalid light. On the other hand, for example, light that is irregularly reflected as indicated by solid arrows in FIG. 7 reaches the irradiation region Al, but the light loses regularity due to the concave and convex processed surface 23c. Concentration in a part of the upper region can be prevented accurately, and illumination light with high uniformity can be irradiated.

  According to such an embodiment, in addition to the effects obtained in the first embodiment described above, the lighting device 1 can be downsized in the optical axis direction by omitting the light shielding mask, and further, the lighting device. There is an effect that the structure of 1 can be further simplified.

Sectional drawing of the principal part of an illuminating device in connection with the 1st Embodiment of this invention. Same as above, exploded perspective view of lighting device Same as above, (a) is an enlarged plan view showing a main part of the fly-eye lens, and (b) is a cross-sectional view taken along the line II of (a). As above, an explanatory diagram showing the relationship between the light emitted from the fly-eye lens and the light shielding mask As above, an explanatory diagram showing the relationship between the set irradiation area and the irradiation area of each lens unit An exploded perspective view of a lighting device according to a second embodiment of the present invention. As above, an explanatory diagram showing light emitted from the fly-eye lens (A) is a top view which expands and shows the principal part of the fly eye lens which set each lens part to planar rectangular shape, (b) is II-II sectional drawing of (a).

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Illuminating device, 10 ... Light source unit, 12 ... Light emitting diode, 20 ... Lens optical system unit, 23 ... Fly eye lens, 23a ... Lens substrate, 23b ... Lens part, 23c ... Uneven surface, 24 ... Shading mask, 24a ... light-transmitting substrate, 24b ... light-shielding part, 24c ... light-transmitting part

Claims (3)

A light source;
A fly-eye lens in which a plurality of lens parts having a planar circular shape are arranged on a lens substrate, and the light from the light source is incident on each lens part to be superimposed on a specific irradiation area, and is emitted.
An illumination device comprising: a light shielding unit configured to shield at least a region other than the lens portions on the lens substrate.   The lighting device according to claim 1, wherein the light shielding unit is disposed on an emission side of the fly-eye lens. A light source;
A plurality of lens portions having a planar circular shape are arranged on a lens substrate, and each of the lens portions includes a fly-eye lens that emits light from the light source that is superimposed on a specific irradiation area, and is emitted.
An illumination device, wherein a fine unevenness is applied to a region other than the lens portions on the lens substrate.

Images