Lighting equipment

Abstract

The lighting device comprises: a light source; a collimating lens, which is located on the optical axis and is used for allowing the emitted light from the light source to enter and emit the collimated light; and a diffusion lens, which is located on the emission surface side of the collimating lens and is used for allowing the collimated light to enter and diffuse the collimated light, and the diffusion lens comprises: a diffusion part, which is used to diffuse the central light of the collimated light emitted from the central part of the emission surface of the collimating lens; and a non-diffusing part, which allows the peripheral light of the collimated light emitted from the emission surface of the collimating lens outside the central part to pass without diffusion.

Description

Technical Field

[0001] The invention relates to lighting devices such as spotlights. Background Art

[0002] Generally, lighting devices such as spotlights project light emitted from a light source with a narrow-angle distribution. This projected light is required to have no uneven brightness or color and to have clear edges (outlines) of light and dark.

[0003] Fig. 9 is a cross-sectional view showing a first conventional lighting device.

[0004] exist Fig. 9 In the first conventional lighting device, a light source 1 and a collimating lens 2 are formed (see: Patent document 1). The collimating lens 2 includes: an incident surface 21 formed by an inner concave surface 211 and an outer convex surface 212; an exit surface 22 formed by an inner convex surface 221 and an outer conical side surface 222; and a peripheral surface 23 connecting the end of the incident surface 21 and the end of the exit surface 22. The light incident from the light source 1 to the inner concave surface 211 of the incident surface 21 is emitted from the inner convex surface 221 of the exit surface 22 to become the central collimated light L1. On the other hand, the light incident from the light source 1 to the outer convex surface 212 of the incident surface 21 is totally reflected by the peripheral surface 23 and emitted from the outer conical side surface 222 of the exit surface 22 to become the peripheral collimated light L2. Both the central collimated light L1 and the peripheral collimated light L2 as the projection light become parallel to the optical axis A. X In addition, the central collimated light L1 and the peripheral collimated light L2 are aligned with respect to the optical axis A. X symmetry.

[0005] Fig.10 Indicates that Fig. 9 The projection light pattern on the virtual screen obtained by the lighting device, (A) represents the light source 1 relative to the optical axis A of the collimating lens 2 X In the case of a square light-emitting surface, (B) represents the optical axis A of the light source 1 relative to the collimating lens 2 X A case with a circular luminous surface.

[0006] like Fig.10 As shown, no matter the light emitting surface of the light source 1 is square or circular, in the projected light pattern, the central collimated light L1 and the peripheral collimated light L2 overlap to obtain light and dark with clear edges.

[0007] The second conventional lighting device utilizes Fig.11 The secondary optical system projection lens shown in (A) diffuses the light focused by the primary optical system to form projection light (see: Patent Document 2). In this case, the projection lens is a lens array having a plurality of hexagonal convex lenses 101 arranged on the incident surface. Fig.11 (B), the parallel light 101a incident vertically on the hexagonal convex lens 101 becomes relative to the optical axis A X 360° diffused light 101b diffuses in all directions of 360°. In addition, when the hexagonal convex lenses 101 are arranged on the emission surface, the parallel light perpendicularly incident on the hexagonal convex lenses 101 is also relative to the optical axis A. X The light is diffused in all directions of 360 degrees. Thus, the light source shape in the projection light pattern is blurred to eliminate brightness unevenness, and the color unevenness is eliminated by mixing the separated colors, so that a uniform projection light pattern can be obtained.

[0008] Prior Art Literature

[0009] Patent Literature

[0010] Patent Document 1: Japanese Patent Application Publication No. 2014-22077

[0011] Patent Document 2: WO2016-186180 Summary of the invention

[0012] Problems to be solved by the invention

[0013] However, in Fig. 9 In the first conventional lighting device shown, the shape of the light source 1 is projected, resulting in uneven brightness. In addition, when the light emitted from the light source 1, such as a white light emitting diode (LED) element, has a chromaticity difference at each emission point and emission angle, color unevenness reflecting the chromaticity difference of the light source 1 is generated. Furthermore, color unevenness caused by the chromatic aberration of the collimating lens 2 also occurs. In this way, there is a problem of uneven brightness and uneven color.

[0014] In addition, Fig.11 In the second conventional lighting device shown, the hexagonal convex lens arranged in the area corresponding to the edge of the projection light pattern also diffuses the light incident parallel to the optical axis in all directions of 360° relative to the optical axis, so there is a problem that the clear brightness and darkness of the edge disappears.

[0015] Means for solving problems

[0016] In order to solve the above-mentioned problems, the lighting device of the present invention comprises: a light source; a collimating lens, which is located on the optical axis and is used to allow the emitted light from the light source to be incident and to emit the collimated light; and a diffusion lens, which is located on the emission surface side of the collimating lens and is used to allow the collimated light to be incident and to diffuse the collimated light, and the diffusion lens comprises: a diffusion portion, which is used to diffuse the central light of the collimated light emitted from the central part of the emission surface of the collimating lens; and a non-diffusing portion, which allows the peripheral light of the collimated light emitted from the emission surface of the collimating lens closer to the outside than the central part to pass through without diffusion.

[0017] In addition, the lighting device of the present invention comprises: a light source; a collimating lens, which is used to allow the emitted light from the light source to be incident and to emit the collimated light; and a diffusion lens, which is located on the optical axis and is used to allow the collimated light to be incident and to diffuse the collimated light, the diffusion lens comprising: a first diffusion portion, which is used to diffuse the central light of the collimated light emitted from the central part of the emission surface of the collimated lens; and a second diffusion portion, which is used to diffuse the peripheral light of the collimated light emitted from the outer side than the central part of the emission surface of the collimated lens, the second diffusion portion diffuses the peripheral light only in the rotation direction relative to the optical axis of the diffusion lens.

[0018] Effects of the Invention

[0019] According to the present invention, it is possible to eliminate uneven brightness and uneven color, and to maintain light and dark with clear edges. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 The first embodiment of the lighting device of the present invention is shown, (A) is an overall cross-sectional view, (B) is a lens array view on the emission side of the diffusion lens of (A), and (C) is a partial enlarged view of the diffusion part of (B).

[0021] Figure 2 Show Figure 1 An example of a change of the diffusion lens, (A) is a lens array diagram on the emission side, and (B) is an enlarged cross-sectional view of the fan-shaped convex lens of (A).

[0022] Figure 3 A second embodiment of the lighting device of the present invention is shown, wherein (A) is an overall cross-sectional view, (B) is a lens array diagram on the emission side of the diffusion lens of (A), and (C) is a projection light pattern of the lighting device of (A).

[0023] Figure 4 Show Figure 3 A comparative example of an illumination device, wherein (A) is an overall cross-sectional view, and (B) is a lens array diagram on the emission surface side of the diffusion lens of (A).

[0024] Figure 5 Yes means Figure 3 , Figure 4 A graph of the standardized photometric characteristics of a lighting device.

[0025] Figure 6 Yes means Figure 3 A lens array diagram on the emission side of a modified example of the diffusion lens.

[0026] Figure 7 It is used to illustrate Figure 1 , Figure 3Figure 2 is a diagram of a collimated light pattern of a collimating lens, (A) and (D) are overall cross-sectional views of the collimating lens, (B) and (E) represent collimated light, and (C) and (F) represent projection light patterns projected by the collimating lens.

[0027] Figure 8 It means that the application Figure 1 , Figure 3 A front view of a spotlight device of the lighting device.

[0028] Fig. 9 is a cross-sectional view showing a first conventional lighting device.

[0029] Fig.10 Show Fig. 9 Projection light patterns of the lighting device, (A) shows the case where the light emitting surface of the light source is square, and (B) shows the case where the light emitting surface of the light source is circular.

[0030] Fig.11 A second conventional lighting device is shown, wherein (A) is a diagram of a lens array on the incident surface side, and (B) is an enlarged cross-sectional view of the hexagonal convex lens of (A). DETAILED DESCRIPTION

[0031] Figure 1 The first embodiment of the lighting device of the present invention is shown, (A) is an overall cross-sectional view, (B) is a lens array view on the emission side of the diffusion lens of (A), and (C) is a partial enlarged view of the diffusion part of (B).

[0032] exist Figure 1 In (A), the lighting device shall include Fig. 9 In addition to a light source such as a light emitting diode (LED) element 1 and a collimating lens 2 disposed on the light source 1, a diffusion lens 3A disposed on the collimating lens 2 is also provided. Figure 1 In (B), the diffusion lens 3A has a circular diffusion portion 31 at the center and a non-diffusion portion 32 around the diffusion portion 31. The diffusion portion 31 defining the diffusion region R1 has a Figure 1 The lens array shown in (C) is composed of a plurality of hexagonal convex lenses 31a arranged most densely, so that the optical axis A X The central collimated light L1 incident in parallel is refracted on the convex surface of the hexagonal convex lens 31a and emitted. Therefore, the light passing through the hexagonal convex lens 31a is refracted with respect to the optical axis A. XThe diffused light 31b is diffused in all directions of 360° to form a 360° diffused light 31b. The diffuser 31 is used for the central collimated light (central light) L1 of the collimating lens 2, which contains uneven brightness and uneven color, to be incident on and eliminate the uneven brightness and uneven color. On the other hand, no lens is formed in the non-diffusion part 32 of the specified non-diffusion area, so the non-diffusion part 32 does not diffuse the incident light, but allows it to pass through and emit directly. As a result, the non-diffusion part 32 allows the peripheral collimated light (peripheral light) L2 with clear edge light and dark to be incident on and maintain the clear edge light and dark. In this way, while maintaining the clear edge light and dark, the elimination of uneven brightness and uneven color is achieved.

[0033] In addition, Figure 1 In (A) and (B), the hexagonal convex lens 31a is arranged on the emission surface side of the diffusion lens 3A, but it can also be arranged on the incident surface side and the emission surface side is flat. In addition, although the diffusion part 31 of the diffusion lens 3 corresponds to the central collimated light L1, and the non-diffusion part 32 of the diffusion lens 3A corresponds to the peripheral collimated light L2, they do not need to correspond strictly. Figure 1 In (C), although the hexagonal convex lens 31a is excellent in that it can effectively use a limited space, a circular convex lens, a quadrilateral convex lens or other polygonal lenses that also have a diffusion effect can also be used.

[0034] Figure 2 Show Figure 1 An example of a change of the diffusion lens, (A) is a lens array diagram on the emission side, and (B) is an enlarged cross-sectional view of the fan-shaped convex lens of (A) cut along its short side (width) direction and circumferential direction.

[0035] exist Figure 2 In (A), the diffusion portion 31' of the diffusion lens 3A' has a light source with an optical axis A on its emission surface. X The lens array is composed of a plurality of fan-shaped convex lenses 31'a which are arranged most densely in a radial shape in the circumferential direction. Figure 2 (B), with the optical axis A X The parallel light, that is, the central collimated light L1, which is incident in parallel, is refracted on the convex surface of the sector convex lens 31'a and emitted, and thus becomes a light beam with respect to the optical axis A as shown by the arrow. X The rotation direction diffused light 31'b diffuses only in the rotation direction. Therefore, in this case, the brightness and color unevenness of the central collimated light L1 can be eliminated. Moreover, the light passing through the fan-shaped convex lens 31'a will not diffuse radially outward of the diffusion part 31'. In addition, when the fan-shaped convex lens 31'a is cut along the long side direction and in the radial direction, it becomes a right triangle shape whose height gradually decreases as it moves toward the optical axis Ax. In addition, Figure 2In the embodiment, the fan-shaped convex lens 31'a may be provided on the incident surface side of the diffusion lens 3A', and the emitting surface side may be made a flat surface.

[0036] Figure 3 A second embodiment of the lighting device of the present invention is shown, wherein (A) is an overall cross-sectional view, (B) is a lens array diagram on the emission side of the diffusion lens of (A), and (C) is a projection light pattern of the diffusion lens of (A).

[0037] exist Figure 3 In (A), replace Figure 1 The diffusion lens 3A of (A) is provided with the diffusion lens 3B. Figure 3 In (B), the diffusion lens 3B has a diffusion portion 33 and a non-diffusion portion 34 around the diffusion portion 33. The diffusion portion 33 defining the diffusion region R1' has a portion on the emission surface that is centered on the optical axis A. X A plurality of fan-shaped convex lenses 33a are arranged most densely in a radial direction around the center, and Figure 2 In the same manner as in the case of (B), X The parallel light incident in parallel, that is, the central collimated light L1 and the peripheral collimated light L2, are refracted on the convex surface of the fan-shaped convex lens 33a and are directed relative to the optical axis A. X like Figure 3 On the other hand, the non-diffusion portion 34 defining the non-diffusion region R2' does not form a lens, and therefore, the incident light is not diffused but directly transmitted and emitted.

[0038] The diffuser 33 allows both the central collimated light L1 and the peripheral collimated light L2 to enter. The central collimated light L1 entering the diffuser 33 is directed with respect to the optical axis A. X The central collimated light L1 is diffused only in the rotation direction. At this time, the brightness unevenness and color unevenness of the central collimated light L1 are eliminated. Similarly, the peripheral collimated light L2 incident on the diffusion lens portion 33 is also diffused relative to the optical axis A. X The light diffuses only in the direction of rotation, so the edges do not expand, and thus the sharp edges of light and dark are maintained. Figure 3 As shown in (C), the projection light pattern of the diffusion lens 3B maintains the light and dark with clear edges, and eliminates uneven brightness and color. Figure 3 In the embodiment, the fan-shaped convex lens 33a may be provided on the incident surface side of the diffusion lens 3B.

[0039] Figure 4 Show Figure 3 Comparative example of a lighting device, instead of Figure 3Instead of the diffusion lens 3B, a diffusion lens 3B' is provided. The diffusion lens 3B' has a diffusion portion 33' and a non-diffusion portion 34. The diffusion portion 33' that specifies the diffusion area is a lens array in which a plurality of hexagonal convex lenses 33'a are arranged, into which both the central collimated light L1 and the peripheral collimated light L2 are incident. In this case, the brightness unevenness and color unevenness of the central collimated light L1 and the peripheral collimated light L2 are eliminated. However, the clear brightness and darkness of the edge of the peripheral collimated light L2 will become unclear due to the 360° omnidirectional diffusion of the hexagonal convex lens 33'a close to the edge of the diffusion portion 33'. That is, as Figure 5 The normalized photometric characteristics of the diffuser lens with respect to the emission angle θ are shown in Figure 3 The fan-shaped convex lens 33a of the diffusion part 33 and Figure 4 The hexagonal convex lens 33'a of the diffusion part 33' is designed to be 1 / 2 when the beam angle is 3°. Figure 3 The standardized luminosity I3 and Figure 4 The half-value width Δθ(50%) of the standardized luminous intensity I4 in the case of the hexagonal convex lens 33b is 3°. However, regarding the beam angle Δθ(10%) of 10%, Δθ(10%)=Δθ3 in the case of the fan-shaped convex lens 33a is smaller than Δθ(10%)=Δθ4 in the case of the hexagonal convex lens 33'a. Therefore, it can be seen that the brightness and darkness of the edge are clearer in the case of the diffusion lens 3B using the fan-shaped convex lens 33a than in the case of the diffusion lens 3B' using the hexagonal convex lens 33'a.

[0040] exist Figure 3 In the diffusion lens 33, the farther away from the optical axis A X The larger the width of the fan-shaped convex lens 33a, the farther away from the optical axis A X The greater the curvature of the fan-shaped convex lens 33a, the smaller the light diffusion effect.

[0041] Figure 6 It is shown Figure 3 A lens array diagram on the emission side of a modified example of the diffusion lens.

[0042] exist Figure 6 In (A), replace Figure 3 The fan-shaped convex lens 33a of the diffusion part 33 is provided with an inner fan-shaped convex lens 33a-1 and an outer fan-shaped convex lens 33a-2. In this case, the number of the outer fan-shaped convex lenses 33a-2 is greater than the number of the inner fan-shaped convex lenses 33a-1, that is, the width of the fan-shaped convex lens 33a-2 is less than Figure 3 The width of the fan-shaped convex lens 33a. Therefore, the curvature of the fan-shaped convex lens 33a-2 is Figure 3The curvature of the corresponding part of the fan-shaped convex lens 33a is small, which can increase the diffusion effect of light. Therefore, this helps to eliminate uneven brightness and uneven color. In addition, although two types of fan-shaped convex lenses 33a-1 and 33a-2 are provided, more than three types of fan-shaped convex lenses can also be provided. In this case, the number of the outer fan-shaped convex lenses is also made larger than the number of the inner fan-shaped convex lenses, so that the diffusion efficiency of light becomes larger.

[0043] exist Figure 6 In (B), replace Figure 6 The fan-shaped convex lens 33a-1 of (A) is replaced by a hexagonal convex lens 33a-1'. As a result, the light diffusion effect of the central part of the diffusion part 33 can be improved, and the effect of eliminating uneven brightness and color in the central part of the diffusion part 33 can be further improved. In addition, a circular or other polygonal convex lens can be provided instead of the hexagonal convex lens 33a-1'.

[0044] Figure 7 It is used to illustrate Figure 1 , Figure 3 Diagram of a collimating lens collimating light.

[0045] exist Figure 1 , Figure 3 In Figure 7 As shown in (A), Fig. 9 The collimating lens 2 is constructed in the same manner as in the case of Figure 7 As shown in (B), the light source 1 is incident on the inner concave surface 211 of the incident surface 21, and passes through the inner convex surface 221 of the emitting surface 22 to generate a light beam approximately directly above the emitting surface 22 and aligned with the optical axis A. X Therefore, when the collimated light of the collimating lens 2 is projected, as shown in FIG. Fig. 9 As shown in (C), annular stray light is generated around the projection light pattern.

[0046] In contrast, in Figure 7 In the collimating lens 2' formed as in (D), a concave portion 223 is provided on the inner convex surface 221 of the emitting surface 22'. Figure 7 As shown in (E), the light incident from the inner convex surface 211 leaks from the concave portion 223 through the inner convex surface 221 to the positive side of the emitting surface 22 of the collimating lens 2' as leakage light L4. As a result, if the collimated light of the collimating lens 2' is used as the projection light, Figure 7 As shown in (F) of FIG. 1 , there is no ring-shaped stray light in the projection light pattern.

[0047] Figure 8 It is a perspective view showing a spotlight device using lighting devices 81, 82, ..., 89 of the present invention.

[0048] like Figure 8 As shown, each lighting device 81, 82, ..., 89 irradiates in approximately the same direction, so that the spotlight device reaches about 1 km. In this case, each lighting device 81, 82, ..., 89 is Figure 1 , Figure 2 , Figure 3 , Figure 6 The lighting device can also make the collimating lenses 2 (2') the same and the diffusion lenses different.

[0049] Furthermore, the present invention is also applicable to any modifications within the obvious scope of the above-mentioned embodiments.

[0050] Industrial Applicability

[0051] The lighting device of the present invention can be used as a projector, a searchlight, a landscape lighting device, a wall lighting device, etc. in addition to a spotlight device.

[0052] Description of Reference Numerals

[0053] 1: Light source

[0054] 2.2': Collimating lens

[0055] 21:Entrance surface

[0056] 211: Inner concave surface

[0057] 212: Outer convex surface

[0058] 22, 22': ejection surface

[0059] 221: medial convex surface

[0060] 222: Outer cone side

[0061] 223: concave part

[0062] 101: Hexagonal convex lens

[0063] 3A, 3B, 3B': Diffusion lens

[0064] 31, 31': diffusion part

[0065] 31a: Hexagonal convex lens

[0066] 31'a: fan-shaped convex lens

[0067] 32: Non-diffusion part

[0068] 33, 33': Diffusion

[0069] 33a, 33a-1, 33a-2: fan-shaped convex lens

[0070] 33a-1': Sector convex lens

[0071] 34: Non-diffusion part

[0072] 8: Spotlight device

[0073] 81, 82,…,89: Lighting device

[0074] L1: Central collimated light (center light)

[0075] L2: Peripheral collimated light (peripheral light)

[0076] A X : Optical axis

[0077] R1, R1': Diffusion area

[0078] R2, R2': non-diffusion area.

Claims

1. A lighting device, comprising: Light source (1); a collimating lens (2, 2'), which is located on the optical axis (Ax) of the light source (1) and is used for allowing the emitted light from the light source (1) to enter and emitting collimated light (L1, L2); and a diffusion lens (3A, 3A') located on the emission surface side of the collimating lens (2, 2') for allowing the collimated light (L1, L2) to enter and diffusing the collimated light (L1, L2); The diffusion lens (3A, 3A') has: a diffusion part (31, 31') for diffusing the central light (L1) of the collimated light emitted from the central part of the emission surface (22) of the collimating lens (2, 2'); and a non-diffusing portion (32) for transmitting peripheral light (L2) of the collimated light emitted from the emission surface (22) of the collimating lens (2, 2') at an outer side than the central portion without diffusion; The collimating lens (2, 2') has: An incident surface (21) having an inner concave surface (211) disposed at the center and an outer convex surface (212) disposed outside the inner concave surface (211); An emission surface (22, 22') having an inner convex surface (221) disposed at the center and an outer conical side surface (222) disposed outside the inner convex surface (221); and a peripheral surface (23) connecting the end surface of the incident surface (21) and the end surface of the emitting surface (22, 22'), A recess (223) is provided at the center of the inner convex surface (221) of the emission surface.

2. The lighting device according to claim 1, wherein: The diffusion part (31) includes an array of a plurality of circular or polygonal convex lenses (31a).

3. The lighting device according to claim 1, wherein: The diffusion part (31') includes an array of a plurality of fan-shaped convex lenses (31'a) arranged along the radial direction of the optical axis (Ax) with the optical axis (Ax) of the diffusion lens (3A') as the center.

4. The lighting device according to claim 1, wherein: The light source (1) has a planar light emitting surface on the optical axis (Ax) of the collimating lens (2, 2').

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