Lighting instrument

Abstract

To simplify the structure.SOLUTION: An embedded type lighting instrument is installed embedded in a ground surface and includes: a housing to be embedded in the ground surface; a light source provided at the housing and having a light emitting part; and an optical member which is provided at the housing so as to cover the light emitting part and has a circular column shape. The housing has: a first recessed part in which the optical member is provided; and a light emitting part housing part which is provided on a bottom surface of the first recessed part and in which the light emitting part is provided. A part of the optical member serves as a protruding part protruding from the first recessed part. An end surface, which is opposite to the protruding part, of the optical member is provided with a second recessed part whose area narrows toward the protruding part. A side surface of the second recessed part is a first incidence surface where light from the light emitting part enters. At the protruding part, an emission surface from which the light entering from the first incidence surface is emitted is provided at a peripheral edge.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a lighting device. [Background technology]

[0002] Patent Document 1 discloses an aviation lighting device that has a reflecting section formed of the inner wall surface of a lower lamp body surrounding a light source, and reflects light from the light source and emits it outside the lamp body through a light-transmitting section. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2008-146914 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, the airfield lighting described in Patent Document 1 has a problem in that the light source and lens provided in the lower light body must be covered by the upper light body formed by casting, making the structure complicated.

[0005] The present invention has been made in view of the above circumstances, and has an object to provide a lighting device with a simplified structure. [Means for solving the problem]

[0006] In order to solve the above problems, the lighting fixture of the present invention is, for example, a recessed lighting fixture that is installed by being embedded in the ground, and comprises a housing that is embedded in the ground, a light source that is provided in the housing and has a light-emitting unit, and a cylindrical optical member that is provided in the housing so as to cover the light-emitting unit, the housing having a first recess in which the optical member is provided, and a light-emitting unit accommodating section that is provided on a bottom surface of the first recess and has the light-emitting unit provided inside, a part of the optical member is a protrusion that protrudes from the first recess, and a second recess is provided on an end surface of the optical member opposite the protrusion, the second recess having an area that narrows toward the protrusion, a side surface of the second recess is a first incident surface into which light from the light-emitting unit is incident, and the protrusion is provided on its periphery with an exit surface from which light incident from the first incident surface exits.

[0007] According to the lamp of the present invention, an optical member is provided inside the first recess of the housing, and a part of the optical member is a protrusion protruding from the first recess. A second recess is provided on the end face of the optical member opposite the protrusion, the area of ​​which narrows toward the protrusion, and light from the light emitting unit is incident on the side face (first entrance face) of the second recess, and the light is emitted from the exit face provided on the periphery of the protrusion. In other words, only the optical member is exposed from the housing, and there is no member covering the optical member. This simplifies the structure of the lamp. Also, by making the optical member cylindrical, the strength of the optical member can be increased to prevent breakage.

[0008] The optical member may be a prism having no spherical surface, the protrusion may be a truncated cone shape, and the inclined surface of the side surface of the protrusion may be the emission surface. This makes it easier to process the optical member and reduces manufacturing errors, i.e., variations in the performance of the lamp.

[0009] The light source may have a lens provided to cover the light-emitting unit, a portion of the lens being provided inside the second recess, and the light emitted from the light-emitting unit may be condensed onto the first incident surface. This allows the lens to condense the light emitted from the light-emitting unit and efficiently guide the light to the optical member.

[0010] The lens may be in a spherical or hemispherical shape, a third recess is provided inside the lens, and a ring-shaped convex lens portion is provided on a side surface of the lens, and the convex lens portion is formed so that, when cut by a second surface passing through a first central axis that is the central axis of the lens, the thickness of a portion intersecting a line inclined at a predetermined angle with respect to the first central axis is the thickest, and the light emitted from the light-emitting portion is incident on a second incident surface that is a side surface of a truncated cone-shaped portion of the third recess that has an area that narrows toward the protruding portion, and the convex lens portion may convert the light incident on the second incident surface into parallel light and cause it to be incident on the first incident surface. This makes it possible to most efficiently guide the light emitted from the light-emitting portion to the optical member.

[0011] The second recess may be shaped like a truncated cone, and the angle of inclination of the exit surface with respect to the horizontal plane may be gentler than the angle of inclination of the first entrance surface with respect to the horizontal plane. This makes it possible to make the angle of light exiting from the exit surface with respect to the horizontal plane smaller than the angle of light entering the first entrance surface with respect to the horizontal plane, and to illuminate the light in a direction close to horizontal.

[0012] The protrusion may have a flat surface surrounded by the light exit surface, and the second recess may be located inside the flat surface when viewed along a second central axis that is a central axis of the optical member, thereby increasing the load-bearing capacity of the optical member.

[0013] The first light entrance surface may be roughened, thereby diffusing the light and widening the illumination range of the lamp.

[0014] A plurality of ribs may be provided on the upper end surface of the housing, and the ribs may not overlap the first recess in a plan view, thereby making it possible to protect the optical member. Effect of the Invention

[0015] According to the present invention, the structure can be simplified. [Brief description of the drawings]

[0016] [Figure 1] 1 is a cross-sectional view showing an outline of a lamp 1 according to a first embodiment of the present invention. [Diagram 2] FIG. 2 is a plan view showing an outline of the lamp 1. [Diagram 3] FIG. 2 is a diagram showing an outline of the main parts of the lighting device 1. [Figure 4] 5 is a cross-sectional view showing an outline of a lamp 2 according to a second embodiment of the present invention. FIG. [Diagram 5] 11 is a cross-sectional view showing an outline of a lamp 3 according to a third embodiment of the present invention. [Figure 6] FIG. 2 is a plan view showing an outline of the lamp 3. [Figure 7] 10 is a cross-sectional view showing an outline of a lamp 4 according to a fourth embodiment of the present invention. FIG. [Figure 8] 11 is a cross-sectional view showing an outline of a lamp 5 according to a fifth embodiment of the present invention. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. The lighting device of the present invention is provided at an airport, a heliport, or an emergency landing site to assist aircraft (planes, helicopters, etc.) in taking off and landing, movement within the airport, etc. The lighting device is a recessed lighting fixture that is embedded in the ground.

[0018] <First embodiment> Fig. 1 is a cross-sectional view showing an outline of a lamp 1 according to a first embodiment of the present invention. Fig. 2 is a plan view showing an outline of the lamp 1. Fig. 1 shows a cross-sectional view of the lamp 1 as viewed from the front (hereinafter referred to as a front cross-sectional view), and some of the hatching showing the cross section is omitted. The lamp 1 mainly has a housing 10, a light source 20, and an optical member 30.

[0019] The housing 10 is entirely embedded in the ground G. The housing 10 mainly has a main housing 11 and a cover 12. The main housing 11 is provided with a light source 20 and an optical member 30. The main housing 11 is a metal part (metal casting) made by casting, for example, an aluminum casting. The cover 12 is a member provided on the bottom surface of the main housing 11 (the lower side of the paper surface in FIG. 1).

[0020] 1, the entire housing 10 is embedded in the ground G, and the top end surface 11d of the main housing 11 is located at the same position as the ground G, but the top end surface 11d may be slightly offset (for example, by about a few centimeters) from the ground G. The top end surface 11d may be located below the ground G, or the top end surface 11d may be located above the ground G. That is, in the present invention, the case where the top end surface 11d is located only a small amount above the ground G is also included in the case where the entire housing 10 is embedded in the ground G.

[0021] The light source 20 mainly has a light emitting unit 21, a lens 22, a substrate 23, and a control unit 24. The light emitting unit 21 is, for example, an LED, and is provided on the substrate 23. The control unit 24 includes various components that control the light emitting unit 21, and is provided on the substrate 23. The control unit 24 is provided inside the cover 12.

[0022] The lens 22 is provided on the substrate 23 so as to cover the light emitting portion 21. A portion of the lens 22 is provided inside the recess 30d.

[0023] Lens 22 has a spherical deuterium shape or a hemispherical shape. Lens 22 has a circular base portion that is attached to substrate 23, but the base portion is smaller than the other portions, and lens 22 as a whole can be said to have a spherical deuterium shape or a hemispherical shape.

[0024] A recess 22a is formed inside the lens 22, which makes the inside of the lens 22 hollow. The recess 22a has a truncated cone-shaped portion whose area narrows toward the protrusion 30a. The light emitted from the light-emitting unit 21 is incident on an incident surface 22f (corresponding to a second incident surface of the present invention), which is a side surface of the recess 22a.

[0025] A circular convex lens portion 22b is provided on the side surface of lens 22. Convex lens portion 22b is formed so that, when cut along a plane passing through the central axis (central axis ax) of lens 22 (see FIG. 1), the thickness of the portion intersecting with line 22l inclined at a predetermined angle with respect to central axis ax is the thickest.

[0026] Furthermore, a convex lens portion 22c is provided at the tip of the lens 22 at a position overlapping with the central axis ax.

[0027] The optical member 30 is transparent and cylindrical. The optical member 30 is formed using a transparent material such as glass or resin. In the present invention, the term "transparent" means that visible light can pass through (has translucency), and includes a state in which the light transmittance is extremely high and the other side can be seen through the material (so-called transparent), and a state in which the light transmittance is low due to coloring or the like and the shape of the other side cannot be clearly recognized through the material (so-called translucent).

[0028] In this embodiment, the optical member 30 is a prism that does not have a spherical surface. In the present invention, a prism is a transparent member used to refract light and does not have a curved surface. Therefore, unlike a lens that has a curved surface, a prism does not diverge or focus light.

[0029] The main housing 11 is provided with recesses 11a, 11b and a hole 11c. An optical member 30 is provided inside the recess 11a (corresponding to a first recess of the present invention). When the optical member 30 is provided in the recess 11a, a part of the optical member 30 protrudes from the recess 11a. The part of the optical member 30 protruding from the recess 11a is referred to as a protruding part 30a.

[0030] The protrusion 30a mainly has an emission surface 30b and a flat surface 30c. In this embodiment, the protrusion 30a has a truncated cone shape, and the inclined surface of the side surface of the protrusion 30a is the emission surface 30b. The emission surface 30b is provided on the periphery of the protrusion 30a, and the flat surface 30c is surrounded by the emission surface 30b. The flat surface 30c is located at the tip of the protrusion 30a.

[0031] A hole 11c (corresponding to a light-emitting portion housing portion of the present invention) is provided in the bottom surface of the recess 11a. A recess 11b is provided below the hole 11c (the lower side of the paper surface of FIG. 1), and the hole 11c connects the recess 11a to the recess 11b. A substrate 23 is provided in the recess 11b so that the light-emitting portion 21 faces upward (toward the recess 11a), and thus the light-emitting portion 21 is provided in the hole 11c.

[0032] The light-emitting unit 21 is provided in the hole 11c, and the optical member 30 is provided in the recess 11a, so that the optical member 30 provided in the main housing 11 covers the light-emitting unit 21. Therefore, light from the light-emitting unit 21 is incident on the optical member 30.

[0033] A recess 30d (corresponding to a second recess of the present invention) is provided on the hole 11c side of the optical member 30, in other words, on the end face opposite to the protruding portion 30a. The area of ​​the recess 30d becomes narrower toward the protruding portion 30a. In this embodiment, the recess 30d is in a truncated cone shape.

[0034] The recess 30d mainly has an incident surface 30e (corresponding to a first incident surface of the present invention) and a flat surface 30f. In this embodiment, the recess 30d has a truncated cone shape. The incident surface 30e is a side surface of the recess 30d, and light from the light emitting unit 21 is incident on the incident surface 30e. The light incident on the incident surface 30e passes through the optical member 30 and is emitted from the emission surface 30b. The flat surface 30f is surrounded by the incident surface 30e and is located at the bottom surface of the recess 30d.

[0035] Since the protrusion 30a and the recess 30d are frustum-shaped, the emission surface 30b and the incidence surface 30e are flat and not curved, as shown in Fig. 1. Therefore, the optical member 30 refracts the light incident on the incidence surface 30e, but does not diverge or concentrate the light.

[0036] Fig. 3 is an enlarged view of a portion of Fig. 1, showing the main parts of the lamp 1. The entire housing 10 is embedded in the ground G, and the top end surface 11d of the main housing 11 is aligned with the ground G (see Fig. 1). In other words, the top end surface 11d is aligned with the horizontal plane.

[0037] The entire housing 10 is embedded in the ground G, and the protruding portion 30a protrudes from the ground G. Therefore, a load is directly applied to the optical member 30, but by making the optical member 30 cylindrical, the load resistance can be increased and the strength of the lamp 1 can be maintained. In particular, in order to make the load resistance of the optical member 30 3,140 kPa or more, it is preferable that the thickness t of the optical member 30 be 10 mm or more.

[0038] Since only the optical member 30 is provided in the recess 11a, the protruding height a of the protruding portion 30a from the ground G is small. Therefore, it is unlikely to become an obstacle to aircraft or the like.

[0039] When viewed along the central axis (central axis ax) of the optical member 30, the recess 30d is located inside the flat surface 30c (see FIG. 2). This increases the load-bearing capacity of the optical member 30. In particular, it is preferable that the outer thickness b of the recess 30d is 15 mm or more.

[0040] Next, we will explain the function of the lamp 1. As shown by the arrows in Figure 3, light emitted from the light-emitting unit 21 passes through the lens 22 and the optical member 30, and is emitted from the emission surface 30b to the outside of the lamp 1. In other words, the lamp 1 emits light obliquely outward from the annular emission surface 30b.

[0041] Convex lens portion 22b has an annular shape, and when cut along a plane passing through central axis ax, the thickness of the portion intersecting line 22l inclined at a predetermined angle to central axis ax is the thickest. Also, convex lens portion 22b converts light incident on incident surface 22f into parallel light and causes it to be incident on incident surface 30e.

[0042] The inclination angle θ1 of the exit surface 30b with respect to the horizontal plane is gentler than the inclination angle θ2 of the entrance surface 30e with respect to the horizontal plane. Therefore, the angle of the light exiting from the exit surface 30b with respect to the horizontal plane is smaller than the angle of the light entering the entrance surface 30e. This allows the lamp 1 to shine light in a direction close to horizontal.

[0043] In this embodiment, the inclination angle θ1 is 20°±5°, and the inclination angle θ2 is 78°±5°. This allows light to be emitted at a specified irradiation angle. Also, the inclination of the light emitted from the light exit surface 30b (the portion outside the light exit surface 30b on the two-dot chain line in FIG. 3) with respect to the horizontal direction can be made to substantially coincide with the center of the irradiation angle.

[0044] Here, the illumination angle is the range of angles within which light with a predetermined luminous intensity or more is illuminated, and is indicated by an upward angle when the horizontal direction is 0°. For example, in the case of taxiway lights installed at airports, the predetermined luminous intensity is 2cd or more, and the illumination angle is 3°±3° (0° to 6°). The center of the illumination angle is the median value of the illumination angle, and when the illumination angle is 3°±3°, the center of the illumination angle is 3°.

[0045] Some of the light is emitted upward from the lamp 1. The light emitted upward from the light-emitting unit 21 and incident on the convex lens portion 22c of the lens 22 becomes parallel light by passing through the convex lens portion 22c and is emitted vertically upward from the lamp 1. In this way, the light is emitted directly above (irradiation angle of 90°) and is hardly emitted at an angle (for example, 45°), so workers on the ground, etc. are not dazzled.

[0046] According to this embodiment, the optical member 30 is provided in the recess 11a of the main housing 11 formed by casting, and the entire housing 10 is embedded in the ground G with the protrusion 30a protruding from the ground G, thereby simplifying the structure of the recessed lighting fixture 1.

[0047] For example, in the conventional technology that requires a cast metal housing to be provided on the optical member 30, the structure becomes complicated and the number of parts increases, making assembly difficult. In particular, in the case of optical products such as lighting fixtures, the axes of the parts need to be aligned, and the labor required for assembly increases significantly with the number of parts.

[0048] In contrast, in this embodiment, in which no cast housing is provided on the optical member 30, the optical member 30 only needs to be provided in the recess 11a, and the structure is simplified, which makes assembly easier. Also, in this embodiment, in which no cast housing is provided on the optical member 30, only the protruding portion 30a protrudes from the ground G, and the protruding height a from the ground G is small. This makes it possible to minimize the risk of damage to aircraft or various devices by the lighting device 1.

[0049] Furthermore, according to this embodiment, by making the optical member 30 cylindrical, the optical member 30 can be made thicker, and damage to the optical member 30, i.e., the lamp 1, can be prevented even if a load is applied directly to the optical member 30.

[0050] Furthermore, according to this embodiment, light from the light-emitting unit 21 enters the entrance surface 30e, which is the side surface of the recess 30d, and the light is emitted from the exit surface 30b, which is provided on the periphery of the protrusion 30a, so that the lamp 1 can function as a recessed lamp that illuminates low positions in the entire circumferential direction.

[0051] Furthermore, according to this embodiment, when viewed along the central axis ax, the recess 30d is located inside the flat surface 30c, so that the optical member 30 becomes thicker, and thus the load resistance of the optical member 30 becomes higher.

[0052] Moreover, according to this embodiment, by using the annular convex lens portion 22b, which has the thickest thickness at the portion intersecting with the line 22l inclined at a predetermined angle to the central axis ax when cut on a plane passing through the central axis ax, the light incident on the incident surface 22f is made parallel and made to enter the incident surface 30e, and thus the light irradiated from the light emitting portion 21 can be most efficiently guided to the optical member 30. In order to satisfy the light irradiation angle (e.g., 0° to 6°) and luminous intensity (e.g., 2 cd or more) required for the lamp 1, it is necessary to collect the light in a predetermined direction, but by making the light incident on the incident surface 22f parallel, it is most easy to form the peak luminous intensity (maximum brightness), that is, it is most easy to collect the light in a predetermined direction.

[0053] Furthermore, according to the present embodiment, the optical member 30 is a prism that does not have a curved surface, and therefore is easy to process. Furthermore, by making the optical member 30 easier to process, the processing precision is increased, and thus manufacturing errors, i.e., the variation in performance of the lamp 1, can be suppressed.

[0054] In this embodiment, the incident surface 30e is normally processed (no special surface processing), but the incident surface 30e may be roughened. The roughening may be, for example, a frosted surface. This creates minute irregularities on the surface of the incident surface 30e, diffusing the light and expanding the illumination range of the light of the lamp 1.

[0055] <Second embodiment> A lamp 2 according to a second embodiment of the present invention will be described below. The lamp 2 has a different lens shape from the lamp 1. The same parts as those in the first embodiment are given the same reference numerals and the description will be omitted.

[0056] Fig. 4 is a cross-sectional view (front cross-sectional view) showing an outline of a lamp 2 according to a second embodiment of the present invention. In Fig. 4, hatching showing a cross section is partially omitted. The lamp 2 mainly includes a housing 10, a light source 20A, and an optical member 30.

[0057] The light source 20A mainly includes a light-emitting unit 21, a lens 22A, a substrate 23, and a control unit 24. The lens 22A is provided on the substrate 23 so as to cover the light-emitting unit 21. A portion of the lens 22A is provided inside the recess 30d.

[0058] Lens 22A has a truncated cone shape whose area narrows toward protrusion 30a. Inside lens 22, there is provided a truncated cone shape recess 22d whose area narrows toward protrusion 30a, making the inside of lens 22A hollow.

[0059] The thickness of the side surface 22e of the lens 22A increases toward the protruding portion 30a. The inner surface of the side surface 22e (the side surface of the recess 22d) is the incident surface 22f (corresponding to the second incident surface of the present invention) into which the light irradiated from the light emitting portion 21 is incident. The outer surface of the side surface 22e is the exit surface 22g (corresponding to the second incident surface of the present invention) from which the light incident from the incident surface 22f exits.

[0060] The incident surface 22f and the exit surface 22g may be flat or curved. In this embodiment, the incident surface 22f and the exit surface 22g are flat.

[0061] 4, the light emitted from the light-emitting unit 21 passes through the lens 22A and the optical member 30, and is emitted from the emission surface 30b to the outside of the lamp device 2. That is, the lamp device 2 emits light obliquely outward from the annular emission surface 30b.

[0062] Light radially emitted from light-emitting unit 21 is incident on incident surface 22f. By making the plate thickness of side surface 22e of lens 22A thicker toward protruding portion 30a, the light incident on incident surface 22f is condensed and the light emitted from exit surface 22g is made as close to parallel light as possible.

[0063] The light emitted from the exit surface 22g is incident on the entrance surface 30e. The inclination angle θ1 of the exit surface 30b with respect to the horizontal plane is gentler than the inclination angle θ2 of the entrance surface 30e with respect to the horizontal plane. Therefore, the angle of the light emitted from the exit surface 30b with respect to the horizontal plane is smaller than the angle of the light incident on the entrance surface 30e. This allows the lamp 2 to shine light in a direction close to horizontal.

[0064] According to this embodiment, the light irradiated from the light-emitting unit 21 is condensed by the lens 22A, and made nearly parallel so that it is incident on the incident surface 30e, so that the light irradiated from the light-emitting unit 21 can be efficiently guided to the optical member 30. Furthermore, the lens 22A has a simple shape and is therefore easy to process, which makes it possible to suppress manufacturing errors, i.e., variations in the performance of the lamp 2.

[0065] <Third embodiment> The following describes a lighting device 3 according to a third embodiment of the present invention. The lighting device 3 has a housing shape different from that of the lighting device 2. Note that the same parts as those in the first or second embodiment are given the same reference numerals and descriptions thereof will be omitted.

[0066] Fig. 5 is a cross-sectional view (front cross-sectional view) showing an outline of a lamp device 3 according to a third embodiment of the present invention. In Fig. 5, hatching showing a cross section is partially omitted. Fig. 6 is a plan view showing an outline of the lamp device 3. The lamp device 3 mainly has a housing 10A, a light source 20A, and an optical member 30.

[0067] The housing 10A mainly has a main housing 11A and a cover 12. The main housing 11A is provided with a light source 20 and an optical member 30. The main housing 11A differs from the main housing 11 in that a rib 11e is provided.

[0068] The rib 11e is provided on the upper end surface 11d. The housing 10A is embedded in the ground G except for the rib 11e. The height of the tip of the rib 11e is the same as or higher than the height of the flat surface 30c. Therefore, the optical member 30 can be protected by the rib 11e.

[0069] The rib 11e does not overlap the recess 11a in a plan view (when viewed from above). Therefore, to provide the optical member 30 in the housing 10A, it is sufficient to simply insert the optical member 30 into the recess 11a from above, making assembly easy.

[0070] According to this embodiment, it is not necessary to provide a cast metal housing on the optical member 30, and it is possible to simplify the structure of the recessed lighting device 3. In addition, by providing a rib 11e on the upper end surface 11d, the rib 11e can protect the optical member 30 and prevent damage to the lighting device 3.

[0071] <Fourth embodiment> A lamp 4 according to a fourth embodiment of the present invention will be described below. The lamp 4 differs from the lamp 1 in that it does not have a lens 22. Note that the same parts as those in the first embodiment are given the same reference numerals and descriptions thereof will be omitted.

[0072] Fig. 7 is a cross-sectional view (front cross-sectional view) showing an outline of a lamp 4 according to a fourth embodiment of the present invention. In Fig. 7, hatching showing a cross section is partially omitted. The lamp 4 mainly includes a housing 10, a light source 20B, and an optical member 30.

[0073] The light source 20B mainly includes a plurality of light-emitting units 21, a substrate 23, and a control unit 24. In this embodiment, the light source 20B includes four light-emitting units 21, which are evenly spaced in the circumferential direction. The four light-emitting units 21 are arranged such that their optical axes op are oriented obliquely upward at 45° with respect to the horizontal direction.

[0074] The light emitted from the multiple light-emitting units 21 directly enters the incident surface 30e of the optical member 30, as shown by the arrows in FIG. 7. In the lamp 4, the light source 20B does not have a lens, but has multiple light-emitting units 21, so most of the light emitted from the light-emitting units 21 enters the incident surface 30e. The inclination angle θ1 of the exit surface 30b with respect to the horizontal plane is gentler than the inclination angle θ2 of the incident surface 30e with respect to the horizontal plane. Therefore, the angle of the light emitted from the exit surface 30b with respect to the horizontal plane is smaller than the angle of the light incident on the incident surface 30e. This allows the lamp 4 to shine light in a direction close to horizontal.

[0075] According to this embodiment, even if the light source 20B does not have a lens, it can function as a recessed lighting fixture that illuminates low positions in all circumferential directions by using the optical element 30, which is a prism without a curved surface.

[0076] <Fifth embodiment> A lamp 5 according to a fifth embodiment of the present invention will be described below. The lamp 5 differs from the lamp 4 in that the optical member is a lens. The same parts as those in the first to fourth embodiments are given the same reference numerals and the description thereof will be omitted.

[0077] Fig. 8 is a cross-sectional view (front cross-sectional view) showing an outline of a lamp 5 according to a fifth embodiment of the present invention. Hatching showing a cross section is partially omitted in Fig. 8. The lamp 5 mainly has a housing 10, a light source 20B, and an optical member 30A.

[0078] The optical member 30A is transparent and cylindrical. The optical member 30A is formed using a transparent member such as glass or resin. In this embodiment, the optical member 30A is a lens having a curved surface. In the present invention, a lens is a transparent member having a curved surface on at least one of the surface through which light enters and the surface through which light exits, and diverges or focuses light.

[0079] The optical member 30A is provided inside the recess 11a. A portion of the optical member 30A protruding from the recess 11a is referred to as a protruding portion 30g.

[0080] The protruding portion 30g mainly has an emission surface 30h and a flat surface 30c. The emission surface 30h is provided on the periphery of the protruding portion 30g, and the flat surface 30c is surrounded by the emission surface 30h.

[0081] The emission surface 30h has a truncated cone shape and includes a curved portion 30i, which is a curved surface, and a flat portion 30j, which is a flat surface. Note that the protrusion 30g in this embodiment includes the curved portion 30i, and such a shape including a curved surface is also included in the truncated cone shape of the present invention.

[0082] A recess 30k is provided on the hole 11c side of the optical member 30A, in other words, on the end face opposite to the protrusion 30g. The recess 30k mainly has an incident surface 30l (corresponding to a first incident surface of the present invention) and a flat surface 30f. The incident surface 30l is a side surface of the recess 30k, and light from the light emitting unit 21 is incident on the incident surface 30l. The flat surface 30f is surrounded by the incident surface 30l and is located at the bottom surface of the recess 30k.

[0083] 8, the light emitted from the light-emitting unit 21 enters the optical member 30A from the incident surface 30l, passes through the optical member 30A, and is emitted from the exit surface 30h to the outside of the lamp 5. That is, the lamp 5 emits light obliquely outward from the annular exit surface 30h.

[0084] Since the incident surface 30l is a curved surface, the light radially emitted from the light-emitting unit 21 is collected by the incident surface 30l and guided to the emission surface 30h. Therefore, the light emitted from the light-emitting unit 21 can be efficiently guided to the emission surface 30h.

[0085] The inclination angle θ3 of the plane connecting both ends of emission surface 30h with respect to the horizontal plane (here, the inclination angle θ3 of flat surface portion 30j) is gentler than the inclination angle θ4 of the plane connecting both ends of incidence surface 30l with respect to the horizontal plane. Therefore, the angle of light emitted from emission surface 30h with respect to the horizontal plane is smaller than the angle of light incident on incidence surface 30l. This allows the light fixture 5 to shine in a direction close to horizontal.

[0086] According to the present embodiment, by using a lens for the optical member 30A, even if the light source 20B does not have a lens, the light emitted from the light emitting unit 21 can be used efficiently.

[0087] In this embodiment, the entire incident surface 30l is a curved surface, but the incident surface 30l may be a combination of a curved surface and a flat surface. For example, the vicinity of both ends of the incident surface may be a flat surface, and the other portion may be a curved surface. This allows light incident near both ends of the incident surface to be guided to the exit surface 30h.

[0088] Although the embodiment of the present invention has been described above in detail with reference to the drawings, the specific configuration is not limited to this embodiment, and design changes within the scope of the gist of the present invention are also included. For example, the above example has been described in detail to clearly explain the present invention, and is not necessarily limited to those having all of the configurations described. In addition, it is possible to replace a part of the configuration of the embodiment with the configuration of another embodiment, and it is also possible to add, delete, or replace other configurations to the configuration of the embodiment.

[0089] Also, for example, the term "cylindrical shape" is not limited to a strictly cylindrical shape, but is a concept that includes cases where it can be regarded as the same as a cylindrical shape. Furthermore, "vicinity" means including a certain range (which can be determined arbitrarily) near a reference position. For example, "near an end" is a concept that indicates a certain range of an area near the end, which may or may not include the end. [Explanation of symbols]

[0090] 1, 2, 3, 4, 5: Light equipment 10, 10A: Housing 11, 11A: Main housing 11a, 11b: recess 11c: hole 11d: Upper end surface 11e: Rib 12: Cover 20, 20A, 20B: Light source 21: Light emitting part 22, 22A: Lens 22a: Recess 22b, 22c: convex lens part 22d: Recess 22e: Side 22f:Incidence plane 22g: Output surface 23: Substrate 24: Control unit 30, 30A: Optical components 30a, 30g: Protrusion 30b, 30h: Output surface 30c: flat surface 30d, 30k: recessed 30e, 30l: entrance surface 30f: flat surface 30i: Curved part 30j: Flat part

Claims

1. An embedded luminaire installed by being embedded in the ground, comprising: a housing embedded in the ground; a light source provided in the housing and having a light-emitting portion; a cylindrical optical member provided in the housing so as to cover the light-emitting portion; and the housing has a first recess in which the optical member is provided, and a light-emitting portion housing portion provided on the bottom surface of the first recess and in which the light-emitting portion is provided; a part of the optical member is a protruding portion protruding from the first recess; a second recess whose area becomes narrower as it goes toward the protruding portion is provided on an end surface of the optical member on the side opposite to the protruding portion; a side surface of the second recess is a first incident surface on which light from the light-emitting portion is incident; an emission surface through which the light incident from the first incident surface exits is provided on the peripheral edge of the protruding portion. A luminaire characterized by the above.

2. The optical member is a prism having no spherical surface, the protruding portion has a frustum of a cone shape, and an inclined surface of the side surface of the protruding portion is the emission surface. The luminaire according to claim 1, characterized by the above.

3. The light source has a lens provided so as to cover the light-emitting portion, a part of the lens is provided inside the second recess, and condenses the light irradiated from the light-emitting portion onto the first incident surface. The luminaire according to claim 2, characterized by the above.

4. The lens has a spherical segment shape or a hemispherical shape, a third recess is provided inside the lens, an annular convex lens portion is provided on the side surface of the lens, the convex lens portion is formed such that when cut by a second plane passing through a first central axis which is the central axis of the lens, the thickness of a portion intersecting a line inclined at a predetermined angle with respect to the first central axis is the thickest, the light irradiated from the light-emitting portion is incident on a second incident surface which is a side surface of a frustum of a cone-shaped portion whose area becomes narrower as it goes toward the protruding portion in the third recess, the convex lens portion makes the light incident on the second incident surface into parallel light and makes it incident on the first incident surface. The luminaire according to claim 3, characterized by the above.

5. The second recess has a frustum of a cone shape, an inclination angle of the emission surface with respect to a horizontal plane is gentler than an inclination angle of the first incident surface with respect to the horizontal plane. The luminaire according to any one of claims 2 to 4, characterized by the above.

6. The protruding portion has a flat surface surrounded by the emission surface. When viewed along the second central axis which is the central axis of the optical member, the second concave portion is located inside the flat surface The lighting device according to any one of claims 1 to 4, characterized in that.

7. The first incident surface is subjected to a roughening treatment The lighting device according to any one of claims 1 to 4, characterized in that.

8. A plurality of ribs are provided on the upper end surface of the housing, The rib does not overlap with the first concave portion in a plan view The lighting device according to any one of claims 1 to 4, characterized in that.

Images