JP7535753B2 - Optical Components and Lighting Equipment - Google Patents

Description

The present disclosure relates to optical components and lighting fixtures, and more specifically to optical components that control the distribution of illumination light, and lighting fixtures that include such optical components.

As a conventional example, the lens plate for lighting equipment and lighting equipment described in Patent Document 1 are exemplified. The lens plate for lighting equipment described in Patent Document 1 (hereinafter, abbreviated as lens) is formed in a disk shape, with one surface facing in the thickness direction serving as a light entrance surface and the other surface serving as a light exit surface. The light exit surface of the lens is formed in a smooth, flat shape. Meanwhile, a lens area made up of numerous concave lens units is formed over the entire light entrance surface of the lens. The multiple concave lens units are formed in a concave shape that diffuses the light incident on the light entrance surface.

The lighting fixture described in Patent Document 1 is a spotlight that is configured to irradiate light onto a wall surface from above diagonally downward. The lighting fixture described in Patent Document 1 uses the lens to make the brightness (illuminance) of the wall surface uniform.

JP 2019-83105 A

However, with the lens (optical component) described in Patent Document 1, it was difficult to further reduce the difference in the amount of light between the center and periphery of the lens.

The objective of this disclosure is to provide optical components and lighting devices that can improve the uniformity of light.

The optical component according to one aspect of the present disclosure includes a main body formed in a plate shape, a plurality of first protrusions provided on an incident surface of the main body, on which light emitted from a light source is incident, and a plurality of second protrusions provided on an exit surface of the main body opposite to the incident surface. Each of the plurality of first protrusions is formed in an elongated shape with a first direction parallel to the incident surface as a longitudinal direction. The plurality of first protrusions are provided on the incident surface so as to be aligned along a second direction parallel to the incident surface and intersecting with the first direction. The plurality of second protrusions are provided on the exit surface so as to be aligned on concentric circles as viewed from the normal direction of the exit surface. Among the plurality of first protrusions, two or more of the first protrusions adjacent to each other along the second direction overlap with a projection range of the light source on the incident surface , and have a height dimension from the incident surface that is higher than one or more of the first protrusions that do not overlap with the projection range. In the second direction, a sum of width dimensions of the two or more first protrusions overlapping with the projection range is greater than a width dimension of the projection range in the second direction.

A lighting device according to one aspect of the present disclosure includes the optical component, the light source that directs light to the incident surface of the optical component, and a device body that houses the optical component and the light source.

The optical components and lighting fixtures disclosed herein have the advantage of improving the uniformity of light.

FIG. 1 is a perspective view of a lighting fixture according to an embodiment of the present disclosure, viewed obliquely from below. FIG. 2 is a perspective view of the lighting fixture as viewed obliquely from above. FIG. 3 is an exploded perspective view of the above lighting fixture. FIG. 4 is a half cross-sectional view of the above lighting fixture. FIG. 5 is an exploded perspective view of a lamp body in the above lighting fixture. FIG. 6 is a perspective view of an optical component according to an embodiment of the present disclosure, viewed obliquely from above. FIG. 7 is a perspective view of the optical component as viewed obliquely from below. FIG. 8 is a cross-sectional view of a main part of a light source unit in the above lighting fixture. 9A and 9B are diagrams showing light distribution characteristics of a lighting fixture using the optical component of the above embodiment, and FIG. 9B is a diagram showing light distribution characteristics of a lighting fixture using an optical component of a comparative example.

The optical components and lighting devices according to the embodiments of the present disclosure will be described in detail below with reference to the drawings. However, the figures described in the following embodiments are schematic diagrams, and the ratios of the sizes and thicknesses of the components do not necessarily reflect the actual dimensional ratios. Note that the configurations described in the following embodiments are merely examples of the present disclosure. The present disclosure is not limited to the following embodiments, and various modifications are possible depending on the design, etc., as long as the effects of the present disclosure can be achieved.

(1) Overview of the lighting device according to the embodiment (1-1) Overview of the optical component according to the embodiment The optical component 5 according to the embodiment of the present disclosure includes a main body 50 formed in a plate shape, a plurality of first protrusions 51, and a plurality of second protrusions 52. The plurality of first protrusions 51 are provided on the surface of the main body 50, which is an incident surface on which light emitted from the light source (LED 30) is incident. The plurality of second protrusions 52 are provided on the surface of the main body 50, which is an exit surface facing the incident surface. Each of the plurality of first protrusions 51 is formed in an elongated shape with a first direction D1 parallel to the incident surface as a longitudinal direction. The plurality of first protrusions 51 are provided on the incident surface so as to be aligned along a second direction D2 parallel to the incident surface and intersecting the first direction D1. Each of the plurality of second protrusions 52 is provided on the exit surface so as to be aligned on a concentric circle when viewed from the normal direction of the exit surface. Of the multiple first protrusions 51, one or more first protrusions 51A that overlap with the projection range S1 of the LED 30 on the incident surface have a higher height dimension from the incident surface than one or more first protrusions 51 that do not overlap with the projection range S1.

The optical component 5 according to the embodiment focuses the light incident on the entrance surface toward the outside of the main body 50, which is incident on one or more first protrusions 51A that overlap the projection range S1 of the light source (LED 30), thereby improving the uniformity of the light.

(1-2) Overview of lighting device according to an embodiment A lighting device A1 according to an embodiment of the present disclosure comprises an optical component 5 according to an embodiment, a light source (LED 30) that directs light to the incident surface of the optical component 5, and a device body 1 that houses the optical component 5 and the LED 30.

The lighting device A1 according to the embodiment is equipped with the optical component 5 according to the embodiment, thereby improving the uniformity of light (illumination light).

(2) Details of the Lighting Fixture According to the Embodiment The lighting fixture A1 according to the embodiment (hereinafter, abbreviated as lighting fixture A1) is a downlight that is disposed so as to be embedded in an indoor ceiling of, for example, a commercial facility, a hospital, a care facility, an accommodation facility, etc. As shown in Figures 1 to 4, the lighting fixture A1 includes a fixture body 1, a lamp body 2, an optical component 5 according to the embodiment (hereinafter, abbreviated as optical component 5), a seal member 6, a holding member 7, and three mounting fixtures 8.

(2-1) Instrument Body The instrument body 1 has a cylindrical portion 10 having a bottom and a ring-shaped frame portion 11 that protrudes outward from the lower end of the cylindrical portion 10 around the entire circumference of the lower end of the cylindrical portion 10. The cylindrical portion 10 and the frame portion 11 are integrally formed, for example, by drawing a metal plate material. However, the cylindrical portion 10 and the frame portion 11 may be formed separately and then joined together by an appropriate method such as welding.

A circular opening 14 is provided at the bottom of the cylindrical portion 10 (see FIG. 4). Three protrusions 15 are provided on the periphery of the upper surface of the bottom of the cylindrical portion 10 (see FIG. 2). Each protrusion 15 is formed in an arc shape. The three protrusions 15 are arranged at equal intervals along the circumferential direction of the bottom of the cylindrical portion 10.

Three mounting parts 12 are provided on the circumferential surface (side surface) of the cylindrical part 10 (see FIG. 2). Each mounting part 12 has a pair of insertion pieces 120 and a locking groove 121. The pair of insertion pieces 120 are formed in a hook shape (L-shape) when viewed in the axial direction (up-down direction) of the cylindrical part 10. The pair of insertion pieces 120 face each other with a gap between them along the circumferential direction of the cylindrical part 10. The pair of insertion pieces 120 are formed by cutting out a part of the cylindrical part 10 (see FIG. 2).

The lock groove 121 of each mounting portion 12 is provided between a pair of insertion pieces 120 on the circumferential surface of the cylindrical portion 10 (see FIG. 2). The lock groove 121 is formed in a rectangular shape by cutting and raising a part of the cylindrical portion 10 toward the inside of the cylindrical portion 10 (see FIG. 2).

(2-2) Light Body The light body 2 has a light source unit 3 and a support block 4. The light body 2 is housed in the fixture main body 1 (see Figs. 3 and 4).

(2-2-1) Light Source Unit The light source unit 3 includes an LED 30, an optical component 5, a holder 32, a lens cover 33, and a unit body 34 (see Figs. 3 to 5). The LED 30 is a COB (Chip on Board) type white LED for illumination. The light emitting surface of the LED 30 (the surface from which illumination light is emitted) is formed in a circular shape.

The optical component 5 has a disk-shaped main body 50, a plurality of first protrusions 51 formed on a first surface (upper surface) of the main body 50, and a plurality of second protrusions 52 formed on a second surface (lower surface) of the main body 50 (see FIG. 4). Details of the optical component 5 will be described later.

The holder 32 holds the LED 30 and the optical component 5. The holder 32 has a cylindrical peripheral wall 320, a truncated cone-shaped bottom wall 321 protruding upward from the inner peripheral surface of the peripheral wall 320, a mounting base 322 protruding in a truncated cone shape from the center of the bottom wall 321, and a wiring section 323 (see Figures 4 and 5). The peripheral wall 320, the bottom wall 321, the mounting base 322, and the wiring section 323 are integrally formed as a molded body of a synthetic resin material such as polybutylene terephthalate. The LED 30 is supported by the holder 32 so as to cover the window 3220 opening on the upper surface of the mounting base 322. The optical component 5 is supported by the holder 32 so as to cover the opening at the lower end of the peripheral wall 320. The wiring section 323 holds the three electric wires (positive electric wire, negative electric wire, and ground wire) of the power cable C1. These three wires are electrically connected to the LED 30 inside the holder 32.

The unit body 34 is made of a metal material and has a cylindrical shape with a bottom. A part of the holder 32 (bottom wall 321 and mounting base 322) and the LED 30 are housed inside the unit body 34. A base 340 that protrudes toward the inside of the unit body 34 is provided at the center of the bottom surface (top surface) of the unit body 34. The base 340 contacts the back surface of the LED 30 held by the holder 32. In other words, the heat generated by the LED 30 is conducted from the base 340 to the entire unit body 34 and dissipated. In addition, an insertion hole 341 through which a part of the wiring part 323 of the holder 32 is inserted is provided at the end of the bottom surface of the unit body 34 (see FIG. 5). The unit body 34 and the holder 32 are joined by screwing.

The lens cover 33 forms the outer shell of the light source unit 3. The lens cover 33 has a main portion 330, an edge portion 331, a rib 332, a reflecting portion 333, and a pair of bosses 334. The main portion 330, the edge portion 331, the rib 332, the reflecting portion 333, and the pair of bosses 334 are integrally formed as a molded body made of synthetic resin material.

The main part 330 is formed in a shape obtained by cutting out a portion of a spherical shell between a first plane including the center of the spherical shell and a second plane parallel to the first plane. In other words, the outer peripheral surface of the main part 330 is a spherical surface. The edge part 331 is formed in a shape combining a part of a ring and a truncated cone, and is connected to the lower end of the main part 330. The reflecting part 333 is formed in a truncated cone shape and protrudes upward from the lower end of the edge part 331 and toward the inside of the edge part 331. The rib 332 is formed in a shape obtained by cutting out a cylinder with a plane inclined to the axis, and protrudes upward from the upper end of the main part 330. The pair of bosses 334 are each formed in a cylindrical shape and are formed integrally with the main part 330 so as to extend upward along the inner peripheral surface of the edge part 331. The pair of bosses 334 are arranged in opposing positions across the reflecting part 333.

(2-2-2) Support Block The support block 4 has a fixed member 40, a first movable member 41, a second movable member 42, and four shaft portions 43 (see FIG. 5).

The fixing member 40 has a rectangular fixing piece 400 and a pair of support pieces 401 that rise from both ends of the longitudinal direction of the fixing piece 400 in the thickness direction (upward) of the fixing piece 400. Each of the pair of support pieces 401 is provided with an internal thread 402. The fixing piece 400 and the pair of support pieces 401 are integrally formed into a U-shape by bending a single rectangular metal plate.

The fixing member 40 is fixed to the unit body 34 by screwing the fixing piece 400 to the top surface of the unit body 34 with two mounting screws 404. In addition, a screw insertion hole 403 is provided at each end of the longitudinal direction of the fixing piece 400. Then, fixing screws 44 made of tapping screws are inserted one by one into these two screw insertion holes 403. These two fixing screws 44 are screwed one by one into two bosses 334 of the lens cover 33 through holes (not shown) provided on the bottom surface of the unit body 34. In other words, the fixing member 40 is also fixed to the lens cover 33.

The first movable member 41 has a first main piece 410, a pair of first leg pieces 411, and a pair of second leg pieces 412. The first main piece 410 is formed in a rectangular flat plate shape. The pair of first leg pieces 411 are each formed in a rectangular flat plate shape and hang down from both ends of the first main piece 410 in the thickness direction (downward) of the first main piece 410 in the longitudinal direction. The pair of second leg pieces 412 are formed in a rectangular flat plate shape and hang down from both ends of the first main piece 410 in the thickness direction (downward) of the first main piece 410 in the lateral direction. The first main piece 410, the pair of first leg pieces 411, and the pair of second leg pieces 412 are integrally formed by bending a single rectangular metal plate.

A rectangular insertion groove 414 is provided at the center of the first main piece 410 in the longitudinal direction and at both ends of the first main piece 410 in the lateral direction. Each first leg piece 411 is provided with a circular first shaft hole 413. Each second leg piece 412 is provided with a circular second shaft hole 415.

The first movable member 41 is attached to the fixed member 40 so as to be able to swing by two shafts 43. Each shaft 43 is composed of a stepped screw 430, a flat washer 431, and a corrugated washer 432. The pair of first legs 411 of the first movable member 41 are respectively arranged outside the pair of support pieces 401 of the fixed member 40. The stepped screw 430 of the shaft 43 is inserted into the first shaft hole 413 of the first leg piece 411 via the corrugated washer 432 and the flat washer 431, and is screwed into the female thread 402 of the support piece 401. Here, the cylindrical portion 4300 of the stepped screw 430 is fitted into the first shaft hole 413, so that the first movable member 41 is attached to the fixed member 40 so as to be able to swing about the cylindrical portion 4300 of the stepped screw 430 as an axis.

The second movable member 42 has a second main piece 420 formed in a rectangular flat plate shape, and a pair of third leg pieces 421 formed in a rectangular flat plate shape and extending downward from both ends of the second main piece 420 in the thickness direction (downward) of the second main piece 420. The second main piece 420 and the pair of third leg pieces 421 are integrally formed by bending a single rectangular metal plate. A circular screw insertion hole 423 is provided at one end of the second main piece 420 in the longitudinal direction. A female screw 422 is provided at the lower end of each of the third leg pieces 421.

The second movable member 42 is attached to the first movable member 41 so as to be able to swing with the two shafts 43. The pair of third leg pieces 421 of the second movable member 42 are inserted one by one into a pair of insertion grooves 414 provided in the first main piece 410 of the first movable member 41, and are arranged inside the pair of second leg pieces 412 of the first movable member 41. The stepped screw 430 of the shaft 43 is inserted into the second shaft hole 415 of the second leg piece 412 via the corrugated washer 432 and the flat washer 431, and is screwed into the female thread 422 of the third leg piece 421. Here, the cylindrical portion 4300 of the stepped screw 430 is fitted into the second shaft hole 415, so that the second movable member 42 is attached to the first movable member 41 so as to be able to swing with the cylindrical portion 4300 of the stepped screw 430 as an axis.

(2-3) Holding Member The holding member 7 rotatably holds the support block 4 (light body 2) relative to the fixture body 1. The holding member 7 has a holding plate 70, three pressing portions 71, and a fixing screw 72, as shown in Figures 3 and 4 .

The retaining plate 70 is formed into a disk shape from a metal plate material. A rectangular insertion hole 701 is provided in the center of the retaining plate 70. A female screw 700 is provided on the periphery of the retaining plate 70 at a position adjacent to the insertion hole 701 along the longitudinal direction of the insertion hole 701. Furthermore, a circular cable insertion hole 702 is provided at a position adjacent to the insertion hole 701 along the lateral direction of the insertion hole 701 of the retaining plate 70.

The second main piece 420 of the second movable member 42 is inserted into the insertion hole 701 of the holding plate 70 from below the holding plate 70. Then, the fixing screw 72 is inserted into the screw insertion hole 423 of the second main piece 420 arranged on the holding plate 70, and the fixing screw 72 is screwed into the internal thread 402 of the holding plate 70. As a result, the holding plate 70 and the support block 4 are joined by screwing (see Figures 2 and 4).

The retaining plate 70 is attached to the upper surface of the cylindrical portion 10 of the instrument body 1 by being pressed by three pressing portions 71. Each of the three pressing portions 71 is composed of a stepped screw 710 and a flat washer 711. The stepped screw 710 is screwed into a threaded hole provided near the abutment portion 15 on the upper surface of the cylindrical portion 10 via the flat washer 711. However, a gap of the height of the abutment portion 15 is created between the upper surface of the cylindrical portion 10 and the lower surface of the flat washer 711. The peripheral portion of the retaining plate 70 is sandwiched in the gap between the upper surface of the cylindrical portion 10 and the lower surface of the flat washer 711, so that the retaining plate 70 is rotatably attached to the upper surface of the cylindrical portion 10 of the instrument body 1 (see Figures 2-4).

Here, three hemispherical positioning protrusions 16 are provided at equal intervals on the upper surface of the cylindrical portion 10, concentrically with the three screw holes for the shoulder screws 710. These three positioning protrusions 16 can prevent misalignment between the center of the holding plate 70 and the center of the upper surface of the cylindrical portion 10 (see Figures 2-4). A power cable C1 is inserted through the cable insertion hole 702 of the holding plate 70. One end of the power cable C1 is electrically connected to the wiring portion 323 of the light source unit 3. The other end of the power cable C1 is electrically connected to a power supply unit (not shown).

(2-4) Mounting Fixture As shown in Fig. 2, the mounting fixture 8 has a spring piece 80, a mounting piece 81, a retaining piece 82, a locking claw 83, and a pair of reinforcing parts 84. The spring piece 80, the mounting piece 81, the retaining piece 82, the locking claw 83, and the pair of reinforcing parts 84 are integrally formed from a metal suitable for a spring material, such as stainless steel. All three mounting fixtures 8 are formed to have the same shape and the same dimensions.

The spring piece 80 is formed in a long strip shape. The mounting piece 81 is formed in a rectangular shape. The retaining piece 82 is formed in a rectangular shape narrower than the mounting piece 81, and is connected to the mounting piece 81 and the spring piece 80. However, the lower end of the retaining piece 82 connected to the spring piece 80 is curved in a U-shape. The lock claw 83 is formed in a hook shape by cutting out a part of the mounting piece 81. The pair of reinforcing parts 84 are formed in a long bathtub shape by drawing a part of the mounting piece 81 and the retaining piece 82. The pair of reinforcing parts 84 suppress deformation along the thickness direction of the mounting piece 81 and the retaining piece 82.

(2-5) Sealing Member The sealing member 6 has a first contact portion 61, a second contact portion 62, six protrusions 63, six hooking claws 64, a non-contact portion 65, and a flange portion 66 (see FIG. 4). The first contact portion 61, the second contact portion 62, the six protrusions 63, the six hooking claws 64, the non-contact portion 65, and the flange portion 66 are integrally formed from a flexible synthetic resin material such as silicone resin.

The first contact portion 61 is formed in a cylindrical shape. The flange portion 66 is formed in an annular shape and protrudes outward from the lower end of the first contact portion 61. The non-contact portion 65 is formed in a truncated cone shape and is connected to the upper end of the first contact portion 61, protruding upward from the upper end of the first contact portion 61. The second contact portion 62 is formed in an annular shape and protrudes inward from the upper end of the non-contact portion 65.

Each of the six protrusions 63 is formed in a quadrangular prism shape. Each protrusion 63 has one triangular prism-shaped hook claw 64. Each of the six protrusions 63 protrudes outward from the outer circumferential surface of the first contact portion 61 along the thickness direction of the first contact portion 61. However, the six protrusions 63 are arranged in pairs at equal intervals along the circumferential direction of the first contact portion 61.

The pair of protrusions 63 are arranged adjacent to each other along the circumferential direction of the first contact portion 61 with a gap narrower than the width of the mounting piece 81 of the mounting fixture 8 and wider than the width of the retaining piece 82. In addition, the hook claws 64 of each of the pair of protrusions 63 protrude outward from the surface opposite the surface (hereinafter sometimes referred to as the opposing surface) that the protrusions 63 face along the circumferential direction of the first contact portion 61.

(2-6) Mounting of the seal member and the mounting fixture to the fixture body The seal member 6 is inserted into the cylindrical portion 10 of the fixture body 1. At this time, the three sets of protrusions 63 of the seal member 6 are inserted one by one into each of the three sets of insertion holes 13 provided in the lower part of the cylindrical portion 10. Then, the hook claws 64 of each set of protrusions 63 are hooked on the outer edge of each set of insertion holes 13. As a result, the seal member 6 is attached to the fixture body 1 (the cylindrical portion 10) by hooking the six hook claws 64 on the edges of the six insertion holes 13 in the cylindrical portion 10 of the fixture body 1. Note that, when the seal member 6 is attached to the fixture body 1, a part of the lamp body 2 (the lens cover 33) is inserted into the opening of the second contact portion 62 of the seal member 6 (see FIG. 4).

The three mounting fixtures 8 are attached one by one to the three mounting sections 12 of the instrument body 1 to which the seal member 6 is attached. The retaining pieces 82 of the mounting fixture 8 are inserted between a pair of protrusions 63 through a pair of insertion pieces 120 of the mounting section 12 from top to bottom along the outer circumferential surface of the cylindrical section 10. Then, the mounting piece 81 of the mounting fixture 8 is inserted into the space between the pair of insertion pieces 120 of the mounting section 12 and the outer circumferential surface of the cylindrical section 10, and the mounting piece 81 is supported by the pair of insertion pieces 120. Furthermore, when the locking claws 83 of the mounting fixture 8 are inserted into the locking grooves 121 of the mounting section 12, the mounting piece 81 is prohibited from moving upward, and the mounting fixture 8 is attached to the mounting section 12 of the instrument body 1.

(3) Details of Optical Components Next, the optical components 5 will be described in detail with reference to FIGS.

The optical component 5 includes a main body 50, a plurality of first protrusions 51, a plurality of second protrusions 52, a peripheral wall 53, and a plurality of fixing parts 54 (three in the illustrated example). The main body 50, the plurality of first protrusions 51, the plurality of second protrusions 52, the peripheral wall 53, and the plurality of fixing parts 54 are integrally formed as a molded body of a synthetic resin having translucency, such as an acrylic resin or a polycarbonate resin. However, the optical component 5 may be formed of inorganic glass, such as quartz glass.

The peripheral wall 53 is formed in an annular shape so as to rise upward from the periphery of the disk-shaped main body 50. Each of the three fixing parts 54 is formed in a hook shape and protrudes from the outer circumferential surface of the peripheral wall 53. Each of these fixing parts 54 is hooked onto three hook parts 324 (see FIG. 5) provided on the holder 32. In other words, the optical component 5 is fixed to the holder 32 by hooking the three fixing parts 54 onto the three hook parts 324 (see FIG. 4 and FIG. 5).

Each of the multiple (11 in the illustrated example) first protrusions 51 is formed in a long semi-cylindrical shape with the first direction D1 (see FIG. 6) parallel to the incident surface (top surface of the main body 50) as the longitudinal direction. That is, each first protrusion 51 corresponds to a cylindrical lens (also called a cylindrical lens) having a semi-cylindrical refracting surface on the surface facing the LED 30. The multiple first protrusions 51 are arranged in a row on the first surface of the main body 50 so that their axial directions (longitudinal directions) are parallel. The width W1 of the refracting surface of each of the multiple first protrusions 51 is substantially equal, including tolerances that arise during manufacturing (see FIG. 6).

Here, the multiple first protrusions 51 are composed of two types of cylindrical lenses with different curvatures of the refracting surface. However, in the following description, among the 11 first protrusions 51, the three first protrusions 51 with a relatively large curvature of the refracting surface may be referred to as first protrusions 51A, and the eight first protrusions 51 with a relatively small curvature of the refracting surface may be referred to as first protrusions 51B (see FIG. 6). Note that the curvatures of the refracting surfaces of the three first protrusions 51A are equal to each other, and the curvatures of the refracting surfaces of the eight first protrusions 51B are equal to each other.

The three first protrusions 51A, which have a large curvature of the refractive surface, are arranged in the center of the first surface of the main body 50. The eight first protrusions 51B, which have a small curvature of the refractive surface, are arranged along the second direction D2, four on each side of the three first protrusions 51A (see FIG. 6).

Here, the three first protrusions 51A at least partially overlap the projection range S1 of the LED 30 (the light-emitting surface) on the incident surface of the optical component 5 (see FIG. 6). Furthermore, the three first protrusions 51A have a higher height dimension from the first surface of the main body 50 than the first protrusion 51B, which has a smaller curvature of the refractive surface (see FIGS. 6 and 8). In other words, among the multiple first protrusions 51, one or more first protrusions 51A that overlap the projection range S1 have a higher height dimension from the first surface than one or more first protrusions 51B that do not overlap the projection range S1. Note that, in the second direction D2, the total width dimension of the three first protrusions 51A that overlap the projection range S1 is larger than the width dimension (diameter) of the projection range S1 in the second direction D2 (see FIG. 6). However, the number and arrangement of each of the two types of first protrusions 51A and 51B are not limited to the above number and arrangement.

The focal length of the three first protrusions 51A is therefore shorter than the distance between the eight first protrusions 51B. Therefore, the light incident on the three first protrusions 51A is focused in a direction away from the center of the main body 50 compared to the light incident on the eight first protrusions 51B. Therefore, the optical component 5 can relatively reduce the light flux in the center of the main body 50 and relatively increase the light flux around the center of the main body 50 compared to when the height dimensions of the eleven first protrusions 51 are equal (the focal lengths are equal).

The multiple (six in the illustrated example) second protrusions 52 are arranged concentrically on the second surface of the main body 50 to form a Fresnel lens. Therefore, the optical component 5 can be made smaller (particularly in terms of the height dimension from the second surface) than when a single convex lens is provided on the exit surface (second surface of the main body 50).

In the following description, the second protrusions 52 located closest to the center of the main body 50 may be referred to as second protrusions 52A, 52B, 52C, 52D, 52E, and 52F (see FIG. 7).

Of these six second protrusions 52, the five second protrusions 52B, 52C, 52D, 52E, and 52F, excluding the second protrusion 52A, each have a first refracting surface 55A and a second refracting surface 55B. The first refracting surface 55A is formed in a circular ring shape that forms a part of a spherical surface. The second refracting surface 55B is formed in a cylindrical surface shape and faces the first refracting surface 55A of the second protrusion 52 adjacent to the inside (see Figures 7 and 8). In addition, a cylindrical recess 520 (so-called gate mark) is present in the center of the second protrusion 52A (see Figures 7 and 8). However, this recess 520 is not an essential structure for the second protrusion 52A.

Here, the second protrusion 52A located at the center of the second surface of the main body 50 has a lower height dimension from the second surface compared to the other five second protrusions 52B, 52C, 52D, 52E, and 52F (see Figures 7 and 8). Therefore, a part of the light emitted from the refractive surface of the second protrusion 52A is reflected by the second refractive surface 55B of the second protrusion 52B and proceeds to the periphery. Therefore, the optical component 5 can relatively reduce the light beam emitted from the center of the second surface of the main body 50 and relatively increase the light beam emitted toward the periphery of the main body 50 compared to when the height dimensions of the two second protrusions 52A and 52B are equal.

Furthermore, the first refracting surface 55A (including the surface of the recess 520) of the second protrusion 52A, the first refracting surface 55A and the second refracting surface 55B of the second protrusion 52B, and the second refracting surface 55B of the second protrusion 52C are subjected to a fine unevenness processing (so-called embossing). In other words, light that is incident on these embossed refracting surfaces (the first refracting surface 55A and the second refracting surface 55B) is diffused when refracted. However, the embossing may or may not be applied to all of the surfaces of the second protrusion 52 (the first refracting surface 55A and the second refracting surface 55B).

In the optical component 5 configured as described above, each of the first protrusions 51 focuses the incident light in the second direction D2, and hardly focuses the light in the first direction D1. In addition, since the second protrusions 52 form a Fresnel lens, the light that passes through the main body 50 after being focused by the first protrusions 51 is refracted when exiting the second protrusions 52, and is focused in each of the first direction D1 and the second direction D2. Therefore, the optical component 5 can provide the light distribution characteristic of the light emitted from the circular light-emitting surface (surface from which light is emitted) of the LED 30 as an approximately elliptical light distribution characteristic with the first direction D1 as the major axis direction.

(4) Light Distribution Characteristics of Light Fixture Next, a description will be given of the light distribution characteristics of lighting fixture A1 using optical component 5. In the following description, lighting fixture A1 is installed on the ceiling of a hospital room and is used to illuminate bed 90 for an inpatient placed in the hospital room (see FIG. 9 ).

The dashed and dotted line in FIG. 9A shows the light distribution characteristics (isoluminous intensity curves) of lighting device A1, and the dashed and dotted line in FIG. 9B shows the light distribution characteristics (isoluminous intensity curves) of a lighting device of a comparative example. The lighting device of the comparative example uses an optical component different from the optical component 5 of lighting device A1. The optical component in the lighting device of the comparative example (hereinafter referred to as the optical component of the comparative example) differs from the optical component 5 in that the height dimensions from the first surface of the multiple first protrusions are all equal, and that the central second protrusion 52A is formed integrally with the adjacent second protrusion 52B, and the height dimensions from the second surface of all second protrusions 52 are equal.

As shown in FIG. 9B, the light distribution characteristics of the comparative lighting fixture have a dense spacing of iso-illuminance curves in the range from the torso to the legs of person M1 lying on bed 90. In other words, when illuminated by the comparative lighting fixture, the center of person M1's body is the brightest, and the illuminance drops off rapidly the further away from the center of the body.

On the other hand, as shown in FIG. 9A, the light distribution characteristics of lighting device A1 are such that the spacing between the isoluminance curves is sparse in the range from the torso to the legs of person M1 lying on bed 90, compared to the light distribution characteristics of the lighting device in the comparative example. In other words, when illuminated by lighting device A1, the difference in illuminance between the center of person M1's body and the ends of his/her body, such as his/her arms, hands, legs, and feet, is reduced, improving the uniformity of the light.

If the lighting fixture A1 can more uniformly illuminate the body of the person M1 lying on the bed 90, doctors and nurses can check the condition of the person M1 (patient) and improve the workability when administering various treatments.

(6) Summary The optical component (5) according to the first aspect of the present disclosure includes a plate-shaped main body (50), a plurality of first protrusions (51), and a plurality of second protrusions (52). The plurality of first protrusions (51) are provided on the surface of the main body (50) on which light emitted from the light source (LED 30) is incident. The plurality of second protrusions (52) are provided on the surface of the main body (50) on which the light emitted from the light source (LED 30) is incident. The plurality of second protrusions (52) are provided on the surface of the main body (50) on which the light emitted from the light source (LED 30) is incident. The plurality of first protrusions (51) are each formed in an elongated shape with a first direction (D1) parallel to the incident surface as the longitudinal direction. The plurality of first protrusions (51) are provided on the incident surface so as to be aligned along a second direction (D2) parallel to the incident surface and intersecting the first direction (D1). The plurality of second protrusions (52) are each provided on the exit surface so as to be aligned on a concentric circle when viewed from the normal direction of the exit surface. Of the multiple first protrusions (51), one or more first protrusions (51A) that overlap with the projection range (S1) of the light source on the incident surface have a higher height dimension from the incident surface than one or more first protrusions (51B) that do not overlap with the projection range (S1).

The optical component (5) according to the first aspect focuses light incident on the entrance surface, which is incident on one or more first protrusions (51A) that overlap the projection range (S1) of the light source, toward the outside of the main body (50), thereby improving the uniformity of the light.

The optical component (5) according to the second aspect of the present disclosure can be realized by combining it with the first aspect. In the optical component (5) according to the second aspect, it is preferable that each of the multiple first protrusions (51) is a cylindrical lens.

The optical component (5) according to the second aspect has a cylindrical lens for each of the multiple first protrusions (51), so that the light is hardly focused in the axial direction of the cylindrical lens, but is focused in a direction intersecting the axial direction. As a result, the optical component (5) according to the second aspect can further improve the uniformity of the light.

The optical component (5) according to the third aspect of the present disclosure can be realized by combining it with the first or second aspect. In the optical component (5) according to the third aspect, the multiple second protrusions (52) are preferably Fresnel lenses.

The optical component (5) according to the third aspect can be made smaller (particularly in terms of the height dimension from the second surface) than when a single convex lens is provided on the exit surface.

The optical component (5) according to the fourth aspect of the present disclosure can be realized by combining with any one of the first to third aspects. In the optical component (5) according to the fourth aspect, it is preferable that, among the multiple second protrusions, the second protrusion (52A) located at the center of the concentric circle has a lower height dimension from the exit surface than the multiple second protrusions (52B, 52C, 52D, 52E, 52F) that are not located at the center of the concentric circle.

The optical component (5) according to the fourth aspect can relatively reduce the light beam emitted from the center of the second surface of the main body (50) by reflecting a portion of the light emitted from the second protrusion (52A) to the side surface (second refractive surface 55B) of the adjacent second protrusion (52B). As a result, the optical component (5) according to the fourth aspect can further improve the uniformity of the light by relatively increasing the light beam emitted toward the periphery of the main body (50).

The optical component (5) according to the fifth aspect of the present disclosure can be realized by combining with any of the first to fourth aspects. In the optical component (5) according to the fifth aspect, it is preferable that, among the multiple first protrusions (51), two or more first protrusions (51A) adjacent to each other along the second direction (D2) overlap with the projection range (S1). It is preferable that, in the second direction (D2), the sum of the width dimensions of the two or more first protrusions (51A) that overlap with the projection range (S1) is greater than the width dimension of the projection range (S1) in the second direction.

The optical component (5) according to the fifth aspect can further improve the uniformity of light by making most of the light emitted from the light source incident on two or more first protrusions (51A).

The lighting device (A1) according to the sixth aspect of the present disclosure includes an optical component (5) according to any one of the first to fifth aspects, a light source (LED 30) that directs light to the incident surface of the optical component (5), and a device body (1) that houses the optical component (5) and the light source.

The lighting device (A1) according to the sixth aspect can improve the uniformity of light by controlling the light emitted from the light source using the optical component (5).

A1 Lighting fixture 1 Fixture body 5 Optical component 30 LED (light source)
50 Main body 51; 51A; 51B First protrusion 52; 52A; 52B; 52C; 52D; 52E; 52F Second protrusion D1 First direction D2 Second direction S1 Projection range

Claims (5)

A main body formed in a plate shape;
a plurality of first protrusions provided on an incident surface of the main body, on which light emitted from a light source is incident;
a plurality of second protrusions provided on an exit surface of the main body, the exit surface facing the entrance surface;
Equipped with
Each of the first protrusions is formed in an elongated shape with a first direction parallel to the incident surface as a longitudinal direction,
the first protrusions are provided on the incident surface so as to be aligned parallel to the incident surface and along a second direction intersecting the first direction,
the second protrusions are provided on the light exit surface so as to be arranged concentrically when viewed from a normal direction of the light exit surface,
Among the plurality of first protrusions, two or more of the first protrusions adjacent to each other along the second direction overlap with a projection range of the light source on the incident surface, and have a height dimension from the incident surface greater than one or more of the first protrusions that do not overlap with the projection range,
a sum of width dimensions of the two or more first protrusions overlapping with the projection range in the second direction is greater than a width dimension of the projection range in the second direction;
Optical components. Each of the plurality of first protrusions is a cylindrical lens.
The optical component according to claim 1. The plurality of second protrusions are Fresnel lenses.
3. The optical component according to claim 1 or 2. Among the plurality of second protrusions, the second protrusion located at the center of the concentric circle has a height dimension from the emission surface that is smaller than that of the plurality of second protrusions not located at the center of the concentric circle.
The optical component according to any one of claims 1 to 3. An optical component according to any one of claims 1 to 4;
The light source that causes light to be incident on the incident surface of the optical component;
An instrument body that houses the optical components and the light source;
Equipped with
Lighting fixtures.

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