JP2019008926A - Reflection plate and luminaire - Google Patents

Abstract

To provide a reflection plate capable of acquiring a desired light distribution angle and axial luminous intensity.SOLUTION: A reflection plate 24B is used together with a light source 21. An inner peripheral surface 30B of the reflection plate 24B has a dome shape in which a diameter expands toward an opening of a front end part 32B from a rear end part 31B where the light source 21 is disposed. In the inner peripheral surface 30B, curvature decreases toward the front end part 32B side. The inner peripheral surface 30B includes: a first inner peripheral surface 33B in which a facet reflector 301B which is flat or which is a curve protruding radially inside is provided in each of a plurality of divided small regions; and a second inner peripheral surface 34B which is disposed further on the front end part 32B side than the first inner peripheral surface 33B and which has a smooth curve shape.SELECTED DRAWING: Figure 12

Description

  The present invention relates to a reflector used in a lighting device and a lighting device having the reflector.

  Conventionally, a lighting device having a reflecting plate is known. By reflecting the light emitted from the light source against the reflecting plate, the property of the light emitted from the lighting device can be adjusted according to the shape of the reflecting plate. For example, Patent Document 1 discloses an illumination device having a reflection plate made of a plurality of conventional reflection regions.

JP 2010-140669 A

  An illumination device used as a spotlight is required to control its light distribution angle to a desired angle. Even if the light distribution angle is the same, the illumination effect is different if the axial luminous intensity and the central illuminance are different. For this reason, it is preferable that not only the light distribution angle but also the axial luminous intensity and the central illuminance can be controlled.

  In particular, in an illumination device having a narrow light distribution angle (1/2 beam angle is 5 ° to 15 °) or a medium angle (1/2 beam angle is 15 ° to 30 °), the axial luminous intensity and the central illuminance are high. Lighting may be required.

  Moreover, it is desirable that the influence of color unevenness can be reduced as an illumination device even if an LED light source that causes color unevenness depending on the direction of light is used.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a reflecting plate that can obtain a desired light distribution angle and axial luminous intensity, and preferably can reduce color unevenness.

  In order to solve the above-mentioned problem, the invention of the present application is a reflecting plate used together with a light source, and has a dome-shaped inner peripheral surface that increases in diameter from a rear end portion arranged in the vicinity of the light source toward an opening of the front end portion. And the inner peripheral surface has a curvature that decreases toward the front end side, and the inner peripheral surface has a planar shape or a curved shape that protrudes radially inward in each of the plurality of divided small regions. A first inner peripheral surface provided with the facet reflector, and a second inner peripheral surface which is disposed on the front end side with respect to the first inner peripheral surface and has a smooth curved surface.

  According to the invention of the present application, a reflecting plate capable of obtaining a desired light distribution angle and axial luminous intensity is obtained.

It is a side view of the illuminating device which concerns on 1st Embodiment. It is sectional drawing of the illuminating device which concerns on 1st Embodiment. It is sectional drawing of a simulation model. It is sectional drawing of a simulation model. It is sectional drawing of a simulation model. It is a direct horizontal plane illuminance data of a simulation result. It is an isoluminance curve of a simulation result. It is a direct horizontal plane illuminance data of a simulation result. It is an isoluminance curve of a simulation result. It is a direct horizontal plane illuminance data of a simulation result. It is an isoluminance curve of a simulation result. It is sectional drawing of the illuminating device which concerns on 2nd Embodiment. It is sectional drawing of the illuminating device which concerns on 3rd Embodiment. It is the graph which showed the relationship between the ratio of the axial direction of a 1st internal peripheral surface and a 2nd internal peripheral surface, and a light distribution angle. It is sectional drawing of a simulation model. It is sectional drawing of a simulation model. It is a direct horizontal plane illuminance data of a simulation result. It is a direct horizontal plane illuminance data of a simulation result.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

<1. First Embodiment>
FIG. 1 is a side view of a lighting apparatus 1A according to the first embodiment of the present invention. FIG. 2 is a cross-sectional view of the main body 10A of the lighting device 1A. This illuminating device 1A is a so-called spotlight that irradiates light in a specific direction. As an example, the lighting device 1A is attached and fixed to a duct rail disposed on a ceiling.

  As illustrated in FIG. 1, the lighting device 1A supports a main body 10A that irradiates illumination light, a fixed portion 11 that is fixed to the ceiling, and the main body 10A that is rotatable with respect to the fixed portion 11. Arm portion 12.

  As shown in FIGS. 1 and 2, the main body 10 </ b> A includes a light source 21, a heat sink 22, an optical member 23, a reflecting plate 24 </ b> A, a baffle 25, and a support member 26.

  The light source 21 is a COB (Chip on Board) type LED light source. The optical axis of the light source 21 is disposed along the central axis 9 that is the axis that forms the center of the reflector. Hereinafter, the direction along the central axis 9 in which the light source 21 emits light is referred to as “front” or “front side”, and the direction opposite to the front is referred to as “rear side” or “rear side”. A direction along the central axis 9 is referred to as an “axial direction”, a direction along the circumference around the central axis 9 is referred to as a “circumferential direction”, and a direction perpendicular to the central axis 9 is referred to as a “radial direction”. . The light emitting region of COB is, for example, a circle having a diameter of 10 mm to 33 mm.

  Such an LED light source may cause color unevenness between light emitted in the axial direction and light emitted in a direction inclined from the axial direction. In general, axial light has a high color temperature and is slightly bluish, and the color temperature becomes lower and yellowish as it becomes oblique.

  The front surface of the light source 21 is a light emitting surface of the light source 21. On the back surface side of the light emitting surface of the light source 21, that is, on the rear surface side of the light source, a heat sink 22 that is a heat radiating portion is disposed. The heat sink 22 has a light source arrangement part 221 arranged along the back surface of the light source 21 and a plurality of heat radiation fins 222 erected substantially perpendicular to the light source arrangement part 221. The light source 21 is fixed to the front surface of the light source arrangement unit 221. The heat generated in the light source 21 is transmitted to the light source arrangement unit 221 and is dissipated into the air through the heat radiation fins 222.

  The optical member 23 is a translucent member that is at least partially disposed on the front side of the light source 21. The optical member 23 includes a base portion 231 fixed to the heat sink 22, a cylindrical portion 232 that decreases in diameter toward the front side, and a lens portion 233 that covers the front side of the cylindrical portion 232.

  The reflecting plate 24A is an annular member having a center end 9 as a center and an open front end. The reflecting plate 24 </ b> A has a dome-shaped inner peripheral surface 30 </ b> A that increases in diameter from the rear end portion disposed in the vicinity of the light source 21 toward the opening of the front end portion. The inner peripheral surface 30A is arranged along a reference curved surface whose curvature decreases as it goes toward one side in the axial direction. The reference curved surface is arranged on the curved surface of a rotating body that rotates a curve around the central axis 9.

  Nearly the entire inner peripheral surface 30A is provided with a facet reflector 301A in each of a plurality of small regions obtained by dividing the reference curved surface in the axial direction and the circumferential direction. For example, 60 facet reflectors are provided every 6 ° in the circumferential direction. Each facet reflector 301A has a planar reflecting surface.

  In this illuminating device 1A, the light source 21 is arrange | positioned rather than the rear-end part of 24 A of reflecting plates. Further, most of the cylindrical portion 232 of the optical member 23 and the lens portion 233 are accommodated inside the reflecting plate 24A.

  The baffle 25 is a cylindrical member arranged along the central axis 9. The baffle 25 is disposed on the front side of the reflecting plate 24A. The inner peripheral surface of the baffle 25 is provided with a plurality of steps arranged at intervals in the axial direction so that the inner peripheral surface cannot be seen with light.

  The support member 26 is a member that fixes the heat sink 22 and the baffle 25 to each other. The support member 26 and the heat sink 22 are fixed by screwing. Further, the support member 26 and the baffle 25 are fixed by meshing with each other's thread grooves. The support member 26 and the heat sink 22, and the support member 26 and the baffle 24 may be fixed to each other by other fixing methods.

  When a driving current is supplied to the light source 21 from a separate power supply device (not shown) outside the illumination device 1A, light is emitted centering on the direction from the light source 21 toward the front side. Of the light emitted from the light source 21, the light incident on the lens unit 233 of the optical member 23 is refracted by the optical member 23 and emitted as light traveling in a predetermined direction.

  On the other hand, of the light emitted from the light source 21, the light incident on the cylindrical portion 232 of the optical member 23 travels toward the inner peripheral surface 30A of the reflecting plate 24A. The light incident on the inner peripheral surface 30A of the reflecting plate 24A is reflected by each facet reflector 301A and emitted as light traveling in a predetermined direction.

  Compared to the case where the inner peripheral surface 30A does not have the facet reflector 301A, the inner peripheral surface 30A has the facet reflector 301A, so that the reflector 24A diffuses the light from the light source 21. For this reason, it can suppress that a color nonuniformity arises in the illumination light after reflection.

  In the following, the presence / absence of the facet reflector and the difference in type will be described with reference to simulation results. The simulation was performed for the first model Ma, which is a reflector model having no facet reflector, the second model Mb having a plurality of curved facet reflectors, and the third model Mc having a plurality of planar facet reflectors. .

  FIG. 3 is a cross-sectional view of the first model Ma. FIG. 4 is a cross-sectional view of the second model Mb. FIG. 5 is a cross-sectional view of the third model Mc. As shown in FIGS. 3 to 5, these simulation models Ma, Mb, and Mc each have a light source 21M, a reflector 24M (24Ma, 24Mb, 24Mc), and a baffle 25M. In addition, these simulation models Ma, Mb, and Mc do not have the translucent optical member 23 which has a lens part.

  In the first model Ma, the inner peripheral surface of the reflecting plate 24Ma is a smooth curved surface along the reference curved surface. In the second model Mb, a curved facet reflector 301Mb protruding inward in the radial direction is provided on the entire inner peripheral surface of the reflector 24Mb. In the third model Mc, a planar facet reflector 301Mc is provided on the entire inner peripheral surface of the reflecting plate 24Mc. 60 facet reflectors 301Mb and 301Mc are provided every 6 ° in the circumferential direction. The reference curved surfaces of the inner peripheral surfaces of the first model Ma, the second model Mb, and the third model Mc have the same shape.

  FIG. 6 is direct horizontal plane illuminance data of the first model Ma. FIG. 7 is an isoluminance curve of the first model Ma. FIG. 8 is direct horizontal plane illuminance data of the second model Mb. FIG. 9 is an isoluminance curve of the second model Mb. FIG. 10 is direct horizontal plane illuminance data of the third model Mc. FIG. 11 is an isoilluminance curve of the third model Mc. 6, 8, and 10, the left half of the data indicates the spread of light. The straight line in the figure represents the angle at which the horizontal illuminance is ½ immediately below, and the diameter (φ) of the ½ illuminance angle and the central illuminance are described for each height. In the right half of the data, the vertical axis represents the distance from the light source, the horizontal axis represents the horizontal distance from directly below the light source, and the range in which the horizontal illuminance is obtained is shown by a curve. 7, 9 and 11 are isoilluminance curves at a position away from the light source 21M in the 3m optical axis direction.

  As shown in FIGS. 6 and 7, in the first model Ma, the central illuminance at a position away from the light source 21M in the 3m optical axis direction is about 130 lx, and the maximum illuminance is about 140 lx. The diameter of the region where the illuminance is 120 lx or more is about 1.4 m. In the first model Ma, the light extraction efficiency compared to the light emitted from the light source 21M is 70.01%.

  As shown in FIGS. 8 and 9, in the second model Mb, the central illuminance and the maximum illuminance at a position away from the light source 21M in the direction of the optical axis by 3 m are about 120 lx, and the diameter of the region where the illuminance is 120 lx or more is about 1 .4m. In the second model Mb, the light extraction efficiency compared with the light emitted from the light source 21M is 68.85%.

  Thus, in the second model Mb, it can be seen that the central illuminance is low and the diameter of the region where the illuminance is 120 lx or more is very small compared to the first model Ma. In other words, the curved facet reflector 301Mb allows sufficient light diffusion and reduces color unevenness. On the other hand, since the diameter of a region where the illuminance is a certain level or less is reduced, the directivity of illumination light is reduced. In addition, the light extraction efficiency is reduced.

  As shown in FIGS. 10 and 11, in the third model Mc, the central illuminance and the maximum illuminance at a position 3 m away from the light source 21M in the optical axis direction are about 12 lx, and the diameter of the region where the illuminance is 120 lx or more is about 1.4 m. In the third model Mc, the light extraction efficiency compared with the light emitted from the light source 21M is 69.92%.

  The third model Mc has a lower central illuminance than the first model Ma. As described above, in the third model Mc, the planar facet reflector 301Mc diffuses the light gathered at the center, thereby reducing color unevenness. On the other hand, in the 3rd model Mc, compared with the 1st model Ma, there is no big difference in the diameter of the area | region whose illumination intensity is 120 lx. Therefore, the reduction rate of the directivity of illumination light is smaller than that of the second model Mb. The third model Mc has lower light extraction efficiency than the first model Ma, but has higher light extraction efficiency than the second model Mb.

  From the results of the above simulation, it can be seen that the planar facet reflector can suppress the reduction of the directivity of illumination light and the illuminance as compared with the curved facet reflector. In the illuminating device 1A according to the first embodiment, a plurality of planar facet reflectors 301A are provided on the inner peripheral surface 30A of the reflecting plate 24A, thereby reducing the color unevenness and reducing the directivity of illumination light and the illuminance. Can be suppressed. That is, a desired light distribution angle and axial luminous intensity can be obtained while reducing color unevenness.

<2. Second Embodiment>
FIG. 12 is a cross-sectional view of the main body 10B of the lighting device 1B according to the second embodiment. This illumination device 1B is also a so-called spotlight that irradiates light in a specific direction, like the illumination device 1A of the first embodiment. This illuminating device 1B differs from the illuminating device 1A of 1st Embodiment only in the shape of the reflecting plate 24B of the main-body part 10B. For this reason, below, only the matter regarding the reflector 24B is demonstrated and description of another matter is abbreviate | omitted.

  The reflection plate 24B is an annular member that is centered on the central axis 9 and is open on the front side. The reflection plate 24B has a dome-shaped inner peripheral surface 30B that increases in diameter as it goes from the rear end portion 31B disposed in the vicinity of the light source 21 toward the opening of the front end portion 32B. The inner peripheral surface 30B is arranged along a reference curved surface that has a curvature that decreases toward the front end portion 32B. The reference curved surface is arranged on the curved surface of a rotating body that rotates a curve around the central axis 9.

  The inner peripheral surface 30B has a first inner peripheral surface 33B including the rear end portion 31B and a second inner peripheral surface 34B including the front end portion 32B. The second inner peripheral surface 34B is disposed closer to the front end portion 32B than the first inner peripheral surface 33B.

  The first inner peripheral surface 33B is provided with facet reflectors 301B in each of a plurality of small regions obtained by dividing the reference curved surface in the axial direction and the circumferential direction. Facet reflector 301B is planar. The facet reflector 301B may have any shape including a curved surface protruding inward in the radial direction.

  The second inner peripheral surface 34B is a smooth curved surface along the reference curved surface.

  A boundary portion 35B between the first inner peripheral surface 33B and the second inner peripheral surface 34B is disposed on the front end portion 32B side with respect to the intermediate position in the axial direction between the front end portion 32B and the rear end portion 31B. That is, the axial range of the first inner peripheral surface 33B is wider than the axial range of the second inner peripheral surface 34B. Moreover, it is preferable that the axial direction range of the 2nd internal peripheral surface 34B is 10% or more of the axial range of the internal peripheral surface 30B. Specifically, the ratio of the axial length of the first inner peripheral surface 33B to the axial length of the second inner peripheral surface 34B is 5: 3.

  When a drive current is supplied to the light source 21, light is emitted centering on the direction from the light source 21 toward the front side. Of the light emitted from the light source 21, the light incident on the lens unit 233 of the optical member 23 is refracted by the optical member 23 and emitted as light traveling in a predetermined direction.

  On the other hand, of the light emitted from the light source 21, the light incident on the cylindrical portion 232 of the optical member 23 travels toward the inner peripheral surface 30B of the reflecting plate 24B. The light incident on the inner peripheral surface 30B of the reflecting plate 24B is reflected on the inner peripheral surface 30B and emitted as light traveling in a predetermined direction.

  Here, as described above, the inner peripheral surface 30B includes the first inner peripheral surface 33B having the facet reflector 301B and the smooth curved second inner peripheral surface 34B having no facet reflector 301B. The first inner peripheral surface 34B diffuses light from the light source 21 compared to the second inner peripheral surface 35B. For this reason, it can suppress that a color nonuniformity arises in the illumination light after irradiation. On the other hand, as compared with the first inner peripheral surface 33B, the second inner peripheral surface 34B does not diffuse the light from the light source 21 and reflects it in a predetermined direction. Therefore, the light reflected on the second inner peripheral surface 34B has high directivity.

  As described above, by providing the facet reflector 301B only on a part of the inner peripheral surface 30B, it is possible to reduce the color directivity and the decrease in the central illuminance while reducing the color unevenness. That is, a desired light distribution angle and axial luminous intensity can be obtained while reducing color unevenness.

  If the range of the first inner peripheral surface 33B is small, the color unevenness of the illumination light may not be sufficiently eliminated. In the lighting device 1B, in particular, the axial range of the first inner peripheral surface 33B is wider than the axial range of the second inner peripheral surface 34B. Thereby, both the elimination of the color unevenness of the illumination light and the suppression of the decrease in the axial luminous intensity can be achieved more reliably.

  Moreover, in this illuminating device 1B, especially the facet reflector 301B is planar. Thereby, compared with the case where facet reflector 301B is curved-surface, the fall of the extraction efficiency of light can be controlled and the directivity of illumination light and the fall of illumination intensity can be controlled.

<3. Third Embodiment>
FIG. 13 is a cross-sectional view of the main body 10C of the lighting device 1C according to the third embodiment. This illuminating device 1C is also a so-called spotlight that irradiates light in a specific direction, similarly to the illuminating device 1A of the first embodiment. This illumination device 1C is different from the illumination device 1A of the first embodiment only in the shape of the reflection plate 24C of the main body 10C. For this reason, below, only the matter regarding the reflector 24C is demonstrated and description of another matter is abbreviate | omitted.

  The reflecting plate 24C is an annular member that is centered on the central axis 9 and that opens on the front side. The reflecting plate 24C has a dome-shaped inner peripheral surface 30C whose diameter increases from the rear end portion 31C disposed in the vicinity of the light source 21 toward the opening of the front end portion 32C.

  The inner peripheral surface 30C has a first inner peripheral surface 33C including a rear end portion 31C and a second inner peripheral surface 34B including a front end portion 32C. The second inner peripheral surface 34B is disposed closer to the front end portion 32B than the first inner peripheral surface 33B.

  The first inner peripheral surface 34C is disposed along a first reference curved surface that has a curvature that decreases toward one side in the axial direction. The second inner peripheral surface 35C is disposed along a second reference curved surface that has a curvature that decreases toward one side in the axial direction. Each of the first reference curved surface and the second reference curved surface is arranged on the curved surface of a rotating body that rotates a curve centered on the central axis 9. In the cross section passing through the central axis 9, the curvature of the second reference curved surface is smaller than the curvature of the curved surface obtained by extending the first reference curved surface toward the front end portion 32C at the same axial position.

  On the first inner peripheral surface 34C, facet reflectors 301C are provided in each of a plurality of small regions obtained by dividing the first reference curved surface in the axial direction and the circumferential direction. On the second inner peripheral surface 35C, facet reflectors 301C are provided in each of a plurality of small regions obtained by dividing the second reference curved surface in the axial direction and the circumferential direction. Thereby, the color nonuniformity of illumination light is reduced. Each of the facet reflectors 301 </ b> C has a curved surface shape protruding radially inward. The facet reflector 301C may have any shape including a planar shape. Further, each of the first inner peripheral surface 34C and the second inner peripheral surface 35C may be a smooth curved surface that does not have the facet reflector 301C.

  When a driving current is supplied to the light source 21, diffused light is emitted centering on the direction from the light source 21 toward the front side. Of the light emitted from the light source 21, the light incident on the lens unit 233 of the optical member 23 is refracted by the optical member 23 and emitted as light traveling in a predetermined direction.

  On the other hand, of the light emitted from the light source 21, the light incident on the cylindrical portion 232 of the optical member 23 travels toward the inner peripheral surface 30C of the reflecting plate 24C. The light incident on the inner peripheral surface 30C of the reflecting plate 24C is reflected on the inner peripheral surface 30C and emitted as light traveling in a predetermined direction.

  Here, in the cross section passing through the central axis 9, the curved surface obtained by extending the first reference curved surface toward the front end portion 32C has a larger curvature at the same axial position than the second reference curved surface. Therefore, in the reflector in which the reference curved surface of the entire inner peripheral surface 30C is a curved surface obtained by extending the first reference curved surface to the front end portion 32C, the reference curved surface of the entire inner peripheral surface 30C extends the second reference curved surface to the rear end portion 31C. The light distribution angle is larger than that of a curved reflector. That is, the light distribution angle of the light reflected on the second inner peripheral surface 35C is smaller than the light distribution angle of the light reflected on the first inner peripheral surface 34C.

  Specifically, the first reference curved surface is designed so that the light distribution angle is 26 ° when the entire inner peripheral surface 30C is arranged along a curved surface obtained by extending the first reference curved surface to the front end portion 32C. ing. Further, the second reference curved surface is designed so that the light distribution angle is 8 ° when the entire inner peripheral surface 30C is arranged along a curved surface obtained by extending the second reference curved surface to the rear end portion 31C. . The ratio between the axial length of the first inner peripheral surface 34C and the axial length of the second inner peripheral surface 35C is 7: 3.

  FIG. 14 shows an axial direction of a first inner peripheral surface 34C designed to have a light distribution angle of 26 °, which is a medium angle, and a second inner peripheral surface 35C designed to have a light distribution angle of 8 °, which is a narrow angle. It is the graph which showed the relationship between a ratio and a light distribution angle. The horizontal axis of the graph of FIG. 14 is the ratio of the first inner peripheral surface 34C in the axial direction to the inner peripheral surface 30C, and the vertical axis is the light distribution angle.

  As shown in FIG. 14, when the ratio of the axial length of the first inner peripheral surface 34C to the axial length of the second inner peripheral surface 35C is 2: 8, the light distribution angle is about 9 °. . When the ratio of the axial length of the first inner peripheral surface 34C to the axial length of the second inner peripheral surface 35C is 5: 5, the light distribution angle is about 12 °. When the ratio between the axial length of the first inner peripheral surface 34C and the axial length of the second inner peripheral surface 35C is 7: 3, the light distribution angle is about 18 °.

  Thus, in this reflector 24C, the light distribution angle is about 18 °. By configuring the inner peripheral surface 30C by combining the two reference curved surfaces designed to have different light distribution angles as described above, it is possible to obtain the reflector 24C having a desired light distribution angle.

  As shown in FIG. 14, in order to realize illumination light having a light distribution angle of about 15 ° to 20 ° by combining a reference curved surface with a medium angle (26 °) and a reference curved surface with a narrow angle (8 °). The ratio in the axial direction of the first inner peripheral surface 34C, which is a medium angle (26 °) component, is 55% to 75%, and the ratio in the axial direction of the second inner peripheral surface 35C, which is a narrow angle (8 °) component, is set. What is necessary is just to set it as 25%-45%.

  The axial distance between the second inner peripheral surface 35C and the baffle 25 is smaller than the axial distance between the first inner peripheral surface 34C and the baffle 25. For this reason, the light which diffuses on the first inner peripheral surface 34 </ b> C and travels at a large angle with respect to the central axis 9 strikes the baffle 25. Thereby, it is suppressed that a light distribution angle becomes large. On the other hand, light that diffuses on the second inner peripheral surface 35 </ b> C and travels at a large angle with respect to the central axis 9 does not easily hit the baffle 25. However, since the light distribution angle on the second inner peripheral surface 35C is smaller than the light distribution angle on the first inner peripheral surface 34C, there is no problem that the light distribution angle increases.

  For this reason, when combining curved surfaces with different reflection angles, the curvature of the first reference curved surface of the first inner peripheral surface 34C arranged on the other side in the axial direction is set to be greater than the curvature of the second reference curved surface of the second inner peripheral surface 35C. Is also assumed to be large. Thereby, it can suppress that illumination light diffuses rather than a desired light distribution angle.

  In addition, in the reflector 24C in which the light distribution angle is designed to be 18 ° by combining different reference curved surfaces, the axial luminous intensity is larger than that of a reflector having an inner peripheral surface designed to have a light distribution angle of 18 ° by a single reference curved surface. Is expensive. In the following, the simulation results when different reference curved surfaces are combined and when a single reference curved surface is used will be described. The simulation was performed for the fourth model Md, which is a reflector model designed with a single reference curved surface, and the fifth model Me, which is a reflector model designed with two different reference curved surfaces.

  FIG. 15 is a cross-sectional view of the fourth model Md. FIG. 16 is a cross-sectional view of the fifth model Me. As shown in FIGS. 15 and 16, each of these simulation models Md and Me includes a light source 21M, a reflector 24M (Md, Me), and a baffle 25M. In addition, these simulation models Md and Me do not have the translucent optical member 23 which has a lens part.

  In the fourth model Md, the inner peripheral surface of the reflector 24Md is arranged along a single reference curved surface designed to have a light distribution angle of 18 °. In the fifth model Md, the reflector Me is designed in the same manner as the reflector 24C according to the second embodiment.

  FIG. 17 is an isoilluminance curve of the fourth model Md. FIG. 18 is an isoilluminance curve of the fifth model Me. As shown in FIG. 17, the fourth model Md has a central illuminance of 4930 lx at a position away from the light source 21M in the 1-m optical axis direction. The light distribution angle of the fourth model Md is about 18 °. As shown in FIG. 18, the fifth model Me has a central illuminance of 5990 lx at a position away from the light source 21M in the 1-m optical axis direction. The light distribution angle of the fifth model Me is about 17 °.

  Thus, the fourth model Md and the fifth model Me have similar light distribution angles. However, the central illuminance of the fifth model Me is about 20% larger than the central illuminance of the fourth model Md.

  Therefore, this reflector 24C can increase the central illuminance by combining different reference curved surfaces. That is, the axial luminous intensity can be increased. Specifically, a medium-angle (18 °) illumination light with a high axial luminous intensity can be realized by combining a medium-angle (26 °) reference curved surface and a narrow-angle (8 °) reference curved surface.

<4. Modification>
As mentioned above, although main embodiment of this invention was described, this invention is not limited to said embodiment.

  In said embodiment, although the illuminating device had the translucent optical member provided with the lens part, this invention is not limited to this. The light emitted from the light source may be incident on the reflecting plate without passing through the translucent optical member provided with the lens unit.

  Moreover, in said embodiment, although the illuminating device was fixed with respect to the ceiling so that rotation was possible, this invention is not limited to this. The lighting device of the present invention may be fixed so as not to rotate with respect to the ceiling, or may be fixed to a structure other than the ceiling such as a wall. In the lighting device of the present invention, the main body may be fixed to a stand.

  Moreover, in said embodiment, although the LED light source which is a light source is arrange | positioned in the back side rather than the rear-end part of a reflecting plate, you may arrange | position inside the space enclosed with the reflecting plate.

Moreover, in said embodiment, although the LED light source is used as a light source, this invention is not limited to this. Other light sources such as an incandescent bulb and a fluorescent lamp may be used as the light source.

  Moreover, you may combine arbitrarily each element which appeared in said each embodiment and modification in the range which does not produce inconsistency.

<5. Extraction of Invention>
As invention extracted from said embodiment and modification, the following invention can be mentioned, for example.

  1st invention is a reflecting plate used with a light source, Comprising: It has a dome-shaped inner peripheral surface which expands as it goes to the opening of a front end part from the rear end part arrange | positioned in the vicinity of the said light source, The said inner periphery The curvature of the surface decreases toward the front end side, and the inner peripheral surface is provided with a flat facet or a curved facet reflector projecting radially inward in each of the plurality of divided small regions. A first inner peripheral surface, and a second inner peripheral surface that is disposed closer to the front end than the first inner peripheral surface and has a smooth curved surface.

  The second invention is the reflecting plate according to the first invention, wherein the boundary between the first inner peripheral surface and the second inner peripheral surface is an intermediate position between the front end portion and the rear end portion of the reflecting plate. It arrange | positions rather than the said front-end part side.

  A third invention is the reflector of the first invention or the second invention, wherein the facet reflector is planar.

  4th invention is a reflecting plate used with a light source, Comprising: It has a dome-shaped inner peripheral surface which expands as it goes to the opening of a front-end part from the rear-end part arrange | positioned in the vicinity of the said light source, The said inner periphery The surface is arranged on the first inner peripheral surface where the curvature decreases toward the front end portion, and on the front end portion side of the first inner peripheral surface, and the second inner surface where the curvature decreases toward the front end portion. In the cross section including the peripheral surface and passing through the optical axis of the light source, the curvature of the second inner peripheral surface is smaller than the curvature of the curved surface obtained by extending the first reference curved surface to the front end side.

  5th invention is a reflecting plate of 4th invention, Comprising: At least one of the said 1st internal peripheral surface and the said 2nd internal peripheral surface is planar or radial direction to each of several divided | segmented small area | regions A curved faceted reflector projecting inward is provided.

  A sixth invention is the reflector according to the fifth invention, wherein the facet reflector is planar.

  7th invention has a light source and the reflecting plate in any one of 1st invention thru | or 6th invention.

  According to 1st invention-7th invention, the reflecting plate which can obtain a desired light distribution angle and axial luminous intensity can be provided.

  In particular, according to the first invention, by providing the facet reflector only on a part of the inner peripheral surface, it is possible to reduce the color directivity and the decrease in central illuminance while reducing color unevenness. That is, a desired light distribution angle and axial luminous intensity can be obtained while reducing color unevenness.

  In particular, according to the second invention, it is possible to more reliably achieve both the elimination of color unevenness of illumination light and the suppression of reduction in axial luminous intensity.

  In particular, according to the third aspect of the invention, compared to the case where the facet reflector has a curved surface shape, it is possible to suppress a decrease in light extraction efficiency and to suppress a decrease in directivity of illumination light and a decrease in illuminance.

  In particular, according to the fourth aspect of the invention, a reflector having a desired light distribution angle can be obtained by configuring the inner peripheral surface by combining two reference curved surfaces designed to have different light distribution angles. . Further, the axial luminous intensity can be increased as compared with a reflector having the same light distribution angle by a single reference curved surface.

  In particular, according to the fifth aspect of the invention, the color unevenness of the illumination light can be reduced.

  In particular, according to the sixth aspect of the present invention, it is possible to suppress a decrease in light extraction efficiency and to suppress a decrease in directivity of illumination light and a decrease in illuminance as compared with a case where the facet reflector is curved.

1A, 1B, 1C Illumination device 9 Central axis 10A, 10B, 10C Main body 21, 21M Light source 23 Optical member 24A, 24B, 24C, 24M, 24Ma, 24Mb, 24Mc, 24Md Reflector 25, 25M Baffle 30A, 30B, 30C Inner peripheral surface 31B, 31C Front end portion 32B, 32C Rear end portion 33B, 33C First inner peripheral surface 34B, 34C Second inner peripheral surface 35B, 35C Boundary portion 301A, 301B, 301C, 301Mb, 301Mc Facet reflector Ma, Mb, Mc, Md, Me Simulation model

Claims (7)

A reflector used with a light source,
Having a dome-shaped inner peripheral surface that increases in diameter from the rear end portion disposed in the vicinity of the light source toward the opening of the front end portion;
The curvature of the inner peripheral surface becomes smaller toward the front end side,
The inner peripheral surface is
A first inner peripheral surface provided with a facet reflector having a curved surface projecting inward in a planar shape or a radial direction in each of the plurality of divided small regions;
A second inner peripheral surface that is disposed on the front end side of the first inner peripheral surface and has a smooth curved surface;
Including a reflector. The reflector according to claim 1,
The boundary part of the said 1st internal peripheral surface and the said 2nd internal peripheral surface is a reflecting plate arrange | positioned in the said front-end part side rather than the intermediate position of the said front-end part and the said rear-end part of the said reflecting plate. The reflector according to claim 1 or 2, wherein
The facet reflector is a flat reflector. A reflector used with a light source,
Having a dome-shaped inner peripheral surface that increases in diameter from the rear end portion disposed in the vicinity of the light source toward the opening of the front end portion;
The inner peripheral surface is
A first inner circumferential surface having a curvature that decreases toward the front end side;
A second inner peripheral surface that is disposed on the front end side of the first inner peripheral surface and has a curvature that decreases toward the front end side;
Including
In the cross section passing through the optical axis of the light source, the curvature of the second inner peripheral surface is smaller than the curvature of the curved surface obtained by extending the first reference curved surface toward the front end side. The reflector according to claim 4,
At least one of the first inner peripheral surface and the second inner peripheral surface is provided with a flat facet or a curved facet reflector protruding inward in the radial direction in each of the divided small regions. . The reflector according to claim 5,
The facet reflector is a flat reflector. A light source;
The reflector according to any one of claims 1 to 6,
A lighting device.