JP2007149551A - Illumination device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an illumination device irradiating illumination light of high output and good balance. <P>SOLUTION: The light irradiated from an HID lamp 12 is reflected at a reflector 11, and incident on a collimation lens 23 in a state of having a prescribed orientation. By this, the light with high parallelism can be generated at the collimation lens 23 even in the case that a light emission part 12a like the HID lamp 12 is difficult to handle as a point light source. Thus, the illumination light of high output and good balance is obtained by making such a parallel light incident on fly-eye lenses 24, 25. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an illumination device that irradiates a specific irradiation area with uniform illuminance.

  Conventionally, as an illuminating device, for example, as disclosed in Patent Document 1, light emitted from a light source is converted into parallel light using a collimation lens, and each cell lens (lens unit) of a fly-eye lens is converted. ) And irradiating a specific irradiation region with uniform illuminance by superimposing light emitted from each cell lens on each other.

By the way, in this type of technology, in order to form illumination light with high uniformity, it is important to generate parallel light with high parallelism by a collimation lens. Therefore, this type of technology is preferably applied particularly to an illumination device using a light emitting diode (LED) that can handle the light emitting unit as a sufficiently small point light source.
JP 2005-190954 A

  However, since an illumination device using LEDs is generally more disadvantageous in terms of light intensity than that using a light source bulb such as an HID lamp (High Intensity Discharge Lamp), its use is limited to some extent.

  On the other hand, when a light source bulb such as a high-power HID lamp is used, it is often difficult to treat the light-emitting portion as a point light source, and the above-mentioned technique of Patent Document 1 has sufficiently high illumination light. May be difficult to obtain.

  An object of this invention is to provide the illuminating device which can irradiate illumination light with high output and high uniformity.

  The present invention includes a light source bulb, a reflector that reflects light emitted from the light source bulb on a reflective concave surface and directs it in a setting direction, a collimation lens that enters the light reflected by the reflector and converts it into parallel light, A fly-eye lens having a plurality of lens portions arranged in a matrix and emitting the light converted into parallel light by the collimation lens to the positions where they are incident on the respective lens portions and overlap each other; And

  According to the illumination device of the present invention, illumination light with high output and high uniformity can be irradiated.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. 1 to 3 relate to a first embodiment of the present invention, FIG. 1 is an exploded perspective view of the illumination device, FIG. 2 is a cross-sectional view of the main part of the illumination device, and FIG. 3A is a light distribution pattern of illumination light. (B) is a chart showing the illuminance distribution of illumination light.

  1 and 2, reference numeral 1 denotes a lighting device. In the present embodiment, the illuminating device 1 is an illuminating device that can emit relatively high-power illuminating light. For example, the illuminating device 1 is suitably used for lighting in a store or the like. The illuminating device 1 includes, for example, a light source unit 10 that uses a high intensity discharge lamp (hereinafter referred to as an HID lamp) 12 that is a high output light source bulb as a light source, and the light source unit 10 is crowned. Lens optical system unit 20.

  The light source unit 10 includes a reflector 11. In the present embodiment, the reflector 11 is an elliptical reflector in which the reflecting concave surface 11a forms a part of a spheroid. For this reason, the reflector 11 has two focal points including the first focal point F1 and the second focal point F2 as optical axes. Have on. The reflector 11 has a valve insertion hole 11b at the base of the reflective concave surface 11a. An HID lamp 12 is inserted into the bulb insertion hole 11b, and the HID lamp 12 is held by the reflector 11 with the light emitting portion 12a positioned at the first focal point F1. Thereby, the light emitted from the light emitting portion 12a of the HID lamp 12 and reflected by the reflecting concave surface 11a is condensed at the second focal point F2.

  The lens optical system unit 20 includes a lens housing 21, a light shielding plate 22 accommodated and held in the lens housing 21, a collimation lens 23, and a pair of fly-eye lenses (first and second fly-eye lenses 24, 25).

  As shown in FIG. 1, in the present embodiment, the lens housing 21 has a substantially rectangular tube shape, and an incident 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 31 is opened at a position facing the entrance 30. As shown in FIG. 2, when the lens housing 21 is crowned on the light source unit 10, the lens housing 21 has a reflective concave surface 11 a facing through the entrance 30, and on the optical axis in the lens housing 21. The second focal point F2 of the reflector 11 is located at

  The lens housing 21 has a lens insertion opening 33 that opens to one side, and the light shielding plate holding grooves 35 that face each other in order from the incident opening 30 side on the inner surface of each side wall adjacent to the lens insertion opening 33. A collimation lens holding groove 36, a first fly eye lens holding groove 37, and a second fly eye lens holding groove 38.

  The light shielding plate 22 is constituted by, for example, a flat plate member having a substantially rectangular shape that is inserted and held in the light shielding plate holding groove 35. Here, the light shielding plate holding groove 35 is set corresponding to the position of the second focal point F2 in the lens housing 21. As a result, the light shielding plate 22 is disposed opposite to the reflector 11 at a position on the optical axis that coincides with the second focal point F2, and a light shielding surface perpendicular to the optical axis is formed in the lens housing 21. Furthermore, a pinhole 22a is opened in the light shielding plate 22 at a position coinciding with the second focal point F2. Thereby, the light-shielding plate 22 allows only the light condensed at the second focal point F2 to pass to the exit 31 side, and shields other light.

  The collimation lens 23 is, for example, a lens member in which a lens portion 23b is integrally formed on the exit side of a substantially rectangular planar lens substrate 23a inserted and held in the collimation lens holding groove 37. And the collimation lens 23 injects the light which passed through the pinhole 22a, converts it into substantially parallel light with the lens part 23b, and radiate | emits it.

  The first fly-eye lens 24 includes, for example, an incident surface projecting downward and an exit surface projecting upward on a planar substantially rectangular lens substrate 24a inserted and held in the first fly-eye lens retaining groove 37. Is a lens member in which a plurality of (for example, 5 × 5) lens portions 24b are integrally formed in a matrix.

  Similarly, for example, the second fly-eye lens 25 protrudes upward and protrudes downward on a planar substantially rectangular lens substrate 25a inserted and held in the second fly-eye lens holding groove 38. A lens member in which a plurality of (for example, 5 × 5) lens portions 25b having an emission surface are integrally formed in a matrix.

  Here, as shown in FIG. 2, the lens portions 24a and 25a of the first and second fly-eye lenses 24 and 25 are directly opposed in a one-to-one correspondence. The relative distance in the optical axis direction of the first and second fly-eye lenses 24 and 25 is the distance that the parallel light incident on the incident surface of the lens portion 24a is collected on the corresponding exit surface of the lens portion 25b. Is set to And the light condensed on the emission surface of each lens part 25b is emitted to a position where they overlap each other, thereby forming a light beam that irradiates a specific irradiation area A (see FIG. 3) with uniform illuminance.

  In the figure, reference numeral 40 denotes a side plate. The side plate 40 has a lens insertion opening after the light shielding plate 22, the collimation lens 23, and the first and second fly-eye lenses 24 and 25 are accommodated in the lens housing 21. 33 is closed.

  According to such an embodiment, the light emitted from the HID lamp 12 is reflected by the reflector 11 and is incident on the collimation lens 23 in a state having a predetermined directivity, so that a light emitting unit is formed like the HID lamp 12. Even when it is difficult to handle 12a as a point light source, the collimation lens 23 can generate parallel light with high parallelism. Then, by making such parallel light enter the fly-eye lenses 24 and 25, it is possible to obtain illumination light with high output and high uniformity.

  In this case, in particular, the reflector 11 is composed of an elliptical reflector, the light emitting part 12a of the HID lamp 12 is arranged at the first focal point F1 set to the elliptical reflector, and the reflected light is condensed at the second focal point F2, and By disposing the light shielding plate 22 with the pinhole 22a opened at a position coincident with the two focal points, unnecessary light can be prevented from entering the collimation lens 23 accurately, and parallel light with higher parallelism can be obtained. Can be generated. Then, by making parallel light having a high degree of parallelism incident on the fly-eye lenses 24 and 25 in this way, it is possible to irradiate a desired irradiation area A with high uniformity as shown in FIG.

  Further, by forming a luminous flux with uniform illuminance by combining the first and second fly-eye lenses 24 and 25, the thickness of each fly-eye lens can be reduced, and the lighting device 1 can be reduced in weight. be able to.

  Next, FIGS. 4 to 9 relate to a second embodiment of the present invention, FIG. 4 is an exploded perspective view of the illumination device, FIG. 5 is a cross-sectional view of a main part of the illumination device, and FIG. FIG. 7A is a contour diagram showing a light distribution pattern of illumination light, FIG. 7B is a diagram showing illumination distribution of illumination light, FIG. 8 is an exploded perspective view showing a modification of the illumination device, and FIG. 9 is an illumination device. It is principal part sectional drawing which shows this modification. In the present embodiment, a point that a light shielding means for limiting light incident on each lens portion 24a is interposed between the collimation lens 23 and the first fly-eye lens 24 is different from the above-described first embodiment. . In addition, about the same structure, a same sign is attached | subjected and description is abbreviate | omitted.

  As shown in FIGS. 4 and 5, in the illumination device 1 of the present embodiment, the light shielding mask holding groove 45 is provided in the lens housing 21 between the collimation lens holding groove 36 and the first fly-eye lens holding groove 37. The light shielding mask 46 as a light shielding means is held in the light shielding mask holding groove 45.

  The light shielding mask 46 includes, for example, a light-transmitting substrate 46a having a substantially rectangular shape inserted and held in the light-shielding mask holding groove 45, and a light shielding portion (light shielding film) 46b formed on the light transmitting substrate 46a. The light-shielding mask 46 is opposed to the incident surface of the first fly-eye lens 24 in the vicinity, and the light-shielding portion 46b transmits light at positions corresponding to the lens portions 24b of the first fly-eye lens 24, respectively. The part 46c is opened. That is, the light-shielding part 46b limits the light that enters the lens parts 24a of the first fly-eye lens 24 from the collimation lens 23 by defining the light-transmissive part 46c on the light-transmissive substrate 46a.

  In the present embodiment, for example, as shown in FIG. 6, each light transmission portion 46 c is opened in an arrow pattern, and thus the illumination device 1 irradiates the irradiation area A ′ in the arrow pattern with a uniform illuminance ( (See FIG. 7).

  According to such an embodiment, when the illumination device 1 is used, for example, at a storefront or the like by limiting the incidence of light to each lens unit 24a using the light shielding mask 46 and forming a pattern with the irradiated image. There is an effect that the functionality can be improved.

  Here, as a light-shielding means interposed between the collimation lens 23 and the first fly-eye lens 24, for example, as shown in FIGS. It is also possible to use the liquid crystal panel 48.

  In this case, the lens housing 21 is provided with a liquid crystal panel holding groove 47 instead of the light shielding mask holding groove 45 between the collimation holding groove 36 and the first fly-eye lens holding groove 37.

  Then, the liquid crystal panel 48 is inserted and held in the liquid crystal panel holding groove 47, and a light-shielding portion having an arbitrary shape is variably displayed on the display portion 48a in association with each lens portion 24b, thereby further improving the functionality of the lighting device 1. Improvements can be realized.

  In the first and second embodiments described above, the fly-eye lens is divided by the first and second fly-eye lenses 24 and 25 formed to be thin in order to reduce the weight of the lighting device 1. However, it is also possible to replace these fly eye lenses 24 and 25 with a single fly eye lens. In this case, it is desirable that the fly-eye lens has optical characteristics of each lens unit so that incident parallel light is condensed on its exit surface.

  Next, FIGS. 10 to 13 relate to a third embodiment of the present invention, FIG. 10 is a cross-sectional view of the main part of the illumination device, and FIG. 11A is a focusing distance between the first and second fly-eye lenses. (B) is a contour diagram showing the light distribution pattern of the illumination light, (c) is a chart showing the illuminance distribution of the illumination light, and FIG. 12 (a) is the first and second diagrams. It is explanatory drawing when a fly eye lens is nearer than a focusing distance, (b) is a contour map which shows the light distribution pattern of the illumination light, (c) is a chart and figure which show the illumination intensity distribution of illumination light 13A is an explanatory diagram when the first and second fly-eye lenses are separated from the in-focus distance, and FIG. 13B is a contour diagram showing a light distribution pattern of the illumination light. Is a chart showing an illuminance distribution of illumination light. The present embodiment is different from the first embodiment described above in that lens moving means for variably adjusting the relative distance between the first and second fly-eye lenses 24 and 25 is provided. In addition, about the same structure, a same sign is attached | subjected and description is abbreviate | omitted.

  As shown in FIG. 10, in this embodiment, the lens casing 21 has a groove portion that is sufficiently longer in the optical axis direction than the thickness of the lens substrate 25a, instead of the second fly-eye lens holding groove 38. A guide groove 138 is formed in which the second fly-eye lens 25 is loosely inserted so as to be movable in the optical axis direction.

  In addition, a plurality of guide bars 150 penetrating through the guide groove 138 in the optical axis direction are provided at appropriate positions of the lens housing 21. Further, the lens housing 21 is provided with a screw mechanism 151 that exposes the male screw portion 151 a in the guide groove 138. In the screw mechanism 151, the male screw portion 151 a is connected to, for example, a knurled 151 b disposed on the front end surface of the lens housing 21, and is rotated integrally with the knurled 151. .

  On the other hand, a hole 25c through which each guide bar 150 passes and a screw hole 25d into which the male screw 151a of the screw mechanism 151 is screwed are formed at appropriate positions on the lens substrate 25a of the fly-eye lens 25. Has been.

  With this configuration, in this embodiment, a function as a lens moving unit that variably adjusts the relative distance between the first and second fly-eye lenses 24 and 25 is realized. That is, in the present embodiment, when the male screw portion 151a rotates in conjunction with the rotation of the knurled 151b, the meshing position of the screw hole 25d on the male screw portion 151a changes, whereby the second fly-eye lens. 25 moves relative to the first fly-eye lens 24 in the optical axis direction. At this time, since the guide bar 150 is penetrated through the main part of the lens substrate 25a, the parallel state of the second fly-eye lens 25 with respect to the first fly-eye lens 24 is maintained.

  Here, the appropriate relative distance between the two fly-eye lenses 24 and 25 is determined by the design values of the lens portions 24b and 25b, the spread angle of substantially parallel light formed by the collimation lens 23, and the like. The appropriate distance in this case is, for example, a focusing distance d0 for condensing the light incident from the incident surface of each lens unit 24b on the output surface of each lens unit 25b, as shown in FIG. is there. Then, as shown in FIGS. 11B and 11C, the uniformity of the irradiation pattern A (d0) becomes the highest at this distance d0. In the present embodiment, the focusing distance d0 is 14.5 mm, for example.

  On the other hand, if it is used for an application in which uniformity and illuminance are not so important, the relative distance between the first and second fly-eye lenses 24 and 25 may be changed as appropriate with the focus distance d0 as a reference. Is possible. In this case, the irradiation range expands when the distance is closer than the focusing distance d0, and the irradiation range decreases when the distance is farther away. However, in general, when the fly-eye lenses 24 and 25 are brought too close, the uniformity of the illuminance decreases, and the four sides of the irradiation pattern gradually curve. On the other hand, if the fly-eye lenses 24 and 25 are moved too far away, the light is not sufficiently transmitted between the corresponding lens portions 24b and 25b, light leakage occurs and the quality of the irradiation pattern is lowered.

  FIG. 12 shows an irradiation pattern A (d1) when the distance between the fly-eye lenses 24 and 25 is set to a distance d1 (for example, d1 = 8.5 mm) closer to the focusing distance d0. FIG. 13 shows an irradiation pattern A (d2) when the distance between the fly-eye lenses 24 and 25 is set to a distance d2 (for example, d2 = 17.5 mm) that is separated from the focusing distance d0.

  According to such an embodiment, the functionality of the lighting device 1 can be improved by variably setting the relative distance between the fly-eye lenses 24 and 25 within a range allowed according to the purpose of use. There is an effect.

  In the present embodiment, the configuration example in which the second fly-eye lens 25 is relatively moved with respect to the first fly-eye lens 24 has been described. However, the present invention is not limited to this, and for example, Of course, the first fly-eye lens 24 may be moved relative to the second fly-eye lens 25. Of course, the configuration of the lens moving means is not limited to that described above.

  Here, in each of the above-described embodiments, for example, a tantalum (Ta) film and a silica (Si) film are alternately laminated on each surface of the collimation lens 23 and the fly-eye lenses 24 and 25, thereby preventing the antireflection film. It is also possible to form If comprised in this way, the loss of the light quantity by the surface reflection of each lens can be suppressed exactly.

  In each of the above-described embodiments, an example in which the reflector 11 is configured by an elliptical reflector has been described. However, instead of the elliptical reflector, a parabolic reflector whose reflecting concave surface forms a rotational parabolic shape is used, and the output from the HID lamp 12 is performed. It is also possible to direct the incident light to the collimation lens 23 while being directed substantially parallel to the optical axis. In this case, since the light reflected by the reflector is not collected, the configuration of the light shielding plate 22 is omitted.

  In each of the above-described embodiments, each of the lens portions 24a and 25a of the first and second fly-eye lenses 24 and 25 is a biconvex lens. For example, the first fly-eye lens 24 is used. Each lens portion 24a is composed of a single convex lens portion having a lens curved surface formed only on the incident surface side, and each lens portion 25b of the second fly-eye lens 25 is formed with a lens curved surface only on the exit surface side. It is also possible to configure with a single convex lens part.

  Of course, the light source bulb applicable to the present invention is not limited to the HID lamp.

An exploded perspective view of a lighting device according to the first embodiment of the present invention. Same as above, main part sectional view of the lighting device Same as the above, (a) is a contour map showing the light distribution pattern of the illumination light, and (b) is a chart showing the illuminance distribution of the illumination light. An exploded perspective view of a lighting device according to a second embodiment of the present invention. Same as above, main part sectional view of the lighting device Same as above, top view of shading mask Same as the above, (a) is a contour map showing the light distribution pattern of the illumination light, and (b) is a chart showing the illuminance distribution of the illumination light. As above, an exploded perspective view showing a modification of the lighting device Same as above, main part sectional view showing a modification of the lighting device Sectional drawing of the principal part of an illuminating device in connection with the 3rd Embodiment of this invention. (A) is explanatory drawing when the 1st, 2nd fly-eye lens is in focus distance, (b) is a contour map which shows the light distribution pattern of the illumination light, (c) is the illumination intensity of illumination light Chart showing distribution (A) is explanatory drawing when the 1st, 2nd fly-eye lens is nearer than a focusing distance, (b) is a contour map which shows the light distribution pattern of the illumination light, (c) is Chart showing illuminance distribution of illumination light (A) is explanatory drawing when the 1st, 2nd fly-eye lens is spaced apart from a focusing distance, (b) is a contour map which shows the light distribution pattern of the illumination light, (c) is Chart showing illuminance distribution of illumination light

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Illuminating device, 10 ... Light source unit, 11 ... Reflector, 11a ... Reflection concave surface, 12 ... High-intensity discharge lamp (light source bulb), 12a ... Light emission part, 20 ... Lens optical system unit, 22 ... Light-shielding plate, 22a ... Pin Hall, 23 ... collimation lens, 24 ... first fly eye lens (fly eye lens), 24b ... lens part, 25 ... second fly eye lens (fly eye lens), 25b ... lens part, 25c ... hole part ( Lens moving means), 25d ... Screw hole (lens moving means) 46 ... Light shielding mask (light shielding means), 48 ... Liquid crystal panel (light shielding means), 48a ... Display unit, F1 ... First focus, F2 ... Second focus, 138 ... Guide groove (lens moving means), 151 ... Screw mechanism (lens moving means)

Claims (5)

A light source bulb,
A reflector that reflects light emitted from the light source bulb on a reflecting concave surface and directs it in a setting direction;
A collimation lens for converting the light reflected by the reflector into parallel light, and
A plurality of lens portions arranged in a matrix, and a fly-eye lens that emits light converted into parallel light by the collimation lens and is emitted from the respective lens portions to be superposed on each other. A lighting device. The reflector is an elliptical reflector in which a light emitting part of the light source bulb is disposed at a first focal point, and the light emitted from the light emitting part is reflected by the reflecting concave surface to be condensed at a second focal point,
A light-shielding plate having a pinhole opened at a position coinciding with the second focal point is disposed opposite the reflector;
The illumination device according to claim 1, wherein the light that has passed through the pinhole is incident on the collimation lens and converted into parallel light.   3. The light shielding device according to claim 1, further comprising a light shielding unit that is interposed between the collimation lens and the fly eye lens and restricts light incident on each lens portion of the fly eye lens. Lighting device.   4. The illumination device according to claim 3, wherein the light shielding means is a transmissive liquid crystal panel that variably displays the shape of the light shielding portion with respect to each of the lens portions. The fly-eye lens is divided into a first fly-eye lens and a second fly-eye lens facing each other on the optical axis,
5. The lens moving device according to claim 1, further comprising a lens moving unit that variably adjusts a relative distance between the first fly-eye lens and the second fly-eye lens. Lighting device.

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