JP6090372B2 - LED unit - Google Patents

Description

  The present invention relates to an LED unit including a reflecting mirror suitable for use in a point light source such as an LED.

Conventionally, a base material (base material) of a reflector is formed of plastic (synthetic resin), an undercoat layer is formed on the surface of the base material, and then a reflective film such as a metal thin film or a dielectric thin film is formed on the undercoat layer. The formed resin-molded reflecting mirror is widely known, and such a reflecting mirror is used in, for example, a vehicle lamp for a headlight (see, for example, Patent Document 1 and Patent Document 2).
On the other hand, in the illumination field, a plurality of reflection surfaces having different reflection directions, reflection areas, and the like are appropriately provided in the plane of the reflector according to a desired light distribution.

JP-A-8-86908 JP-A-11-221517

However, in the resin-molded reflecting mirror, even if the surface shape of each reflecting surface of the base material is formed according to the optical design value, the edge of each reflecting surface is affected by the thickness of the undercoat layer. It does not become. For this reason, there is a problem in that the edge of the irradiation area of the reflection surface is blurred because the light control according to the optical design is not performed at the edge portion of the reflection surface and unintended reflection light is generated.
When the light source is a linear light source such as a discharge lamp, blurring occurs at the edge of the irradiation area due to the characteristics of the light source, so that even if the edge of the reflecting surface is slightly different from the optical design value, the influence is small.
However, when the light source is a point light source such as an LED, an irradiation area that is faithful to the optical design can be formed, so that an irradiation area with clear brightness at the edges can be formed, but the edge of the reflecting surface as described above. If the value is different from the optical design value, blurring of the edge of the irradiation area becomes conspicuous, and a clear and sharp edge cannot be obtained.

  This invention is made | formed in view of the situation mentioned above, and it aims at providing the LED unit which can obtain an irradiation area with a sharp edge even when a point light source is used for a light source.

To achieve the above object, the present invention comprises a plurality continuously provided the reflector with a concave reflecting surface having a plurality of reflecting surfaces, the LED is arranged on each concave reflecting surface, a plurality of the concave reflective surface The irradiation areas are overlapped to form one irradiation area, and the reflection surfaces at both ends of the concave reflection surface provided continuously are directed to direct the light beams of the plurality of LEDs toward the center of the one irradiation area. In the LED unit that is a shadow reflecting surface and is fixed to the bottom surface of the caseless light case , the plurality of LEDs are arranged side by side at a predetermined interval, and the reflecting mirror is concave for each LED on one surface facing the LED. A substantially rectangular parallelepiped shape having a continuous reflecting surface is provided, and a shielding member is provided at a boundary between the reflecting surfaces of the concave reflecting surface and reflecting toward the edge of the one irradiation area in the optical design. Non part Characterized in that the morphism.

Further, the present invention includes a reflecting mirror in which a plurality of concave reflecting surfaces having a plurality of reflecting surfaces are provided , and LEDs are arranged on each concave reflecting surface, respectively , and the plurality of concave reflecting surfaces are overlapped with irradiation areas. one of the irradiated area to form, the reflective surface of both end portions of the concave reflecting surface which is continuously provided, and shadowless reflecting surface for directing light rays of a plurality of the LED in the center of said one illumination area, no In the LED unit fixed to the bottom surface of the shadow lamp case , the plurality of LEDs are arranged side by side at a predetermined interval, and the reflecting mirror is formed by continuously providing a concave reflecting surface for each LED on one surface facing the LEDs. It has a rectangular parallelepiped shape, and the concave reflecting surface is formed by forming a reflecting layer on the surface of the base material, and is a boundary between the reflecting surfaces of the concave reflecting surface, and is directed toward the edge of the one irradiation area in the optical design. Other than the reflective part Wherein forming a reflective layer, characterized in that the said portion to a non-reflective.

  According to the present invention, since no reflected light is generated at the edge and the edge of the irradiation area is not irradiated, blurring of the edge of the irradiation area is suppressed, and a sharp edge can be obtained.

It is a figure which shows the structure of the dental LED operating light which concerns on embodiment of this invention, (A) is the figure seen from the bottom face, (B) is sectional drawing in the II line | wire of (A). It is a figure which shows typically an irradiation area with the structure of the LED unit for shadowless. It is a figure which shows the three surfaces of the front, a plane, and side surface of an LED unit for shadowless. It is a figure which shows typically the directivity direction of the reflected light in a concave reflective surface. It is a figure which shows the manufacturing process of a reflective mirror. It is a schematic diagram which expands and shows the cross section of the boundary of the reflective surfaces of a reflective mirror. It is a figure which shows the comparative example of a reflective mirror typically. It is a figure which shows an example of the characteristic of the LED unit for shadowless.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, a shadowless lamp used for dental treatment is illustrated as an example of a lighting fixture including the LED unit according to the present invention.
FIG. 1 is a diagram showing a configuration of a dental LED surgical light 1 according to the present embodiment, FIG. 1 (A) shows a bottom surface, and FIG. 1 (B) is taken along line II in FIG. 1 (A). It is a figure which shows a cross section.
As shown in the figure, the dental LED surgical lamp 1 is formed of, for example, a resin that covers a horizontally long case body (lamp body) 2 having a bottom opening as a rectangular irradiation opening 2A and the irradiation opening 2A of the case body 2. A transparent cover 3 is provided. As shown in FIG. 1B, the case body 2 includes a bottomed middle case 5 and an upper case 6 that covers the upper side of the middle case 5, and can be surrounded by the middle case 5 and the upper case 6. The space 8 contains an LED drive circuit, a power supply circuit, a heat sink, etc. (not shown). A shadowless LED unit (hereinafter referred to as “shadowless LED unit”) 10 is fixed to the bottom surface 5 </ b> A of the middle case 5.
The transparent cover 3 is configured to suppress light diffusion and deflection during transmission depending on its shape, material, and the like. Moreover, in the lighting fixture which can be used by exposing the LED unit 10, it is not necessary to provide a cover member corresponding to the transparent cover 3.

The shadowless LED unit 10 alone is configured to cause a shadowless effect in the irradiation area. For this reason, the structure for attaching the shadowless LED unit 10 to the case body 2 does not include a structure for tilting the shadowless LED unit 10 as shown in FIG. As a result, the operation of attaching the shadowless LED unit 10 to the case body 2 becomes easy, and the assemblability can be improved.
Hereinafter, the structure of the shadowless LED unit 10 will be described in detail.

FIG. 2 is a diagram schematically showing the configuration and irradiation area of the shadowless LED unit 10, FIG. 2A is a perspective view of the shadowless LED unit 10, and FIG. 2B is a schematic diagram of the irradiation area. It is. FIG. 3 is a view showing three surfaces of the shadowless LED unit 10 including a front surface, a plane surface, and a side surface.
As shown in these drawings, the shadowless LED unit 10 includes a rectangular parallelepiped reflecting mirror 12 and four LEDs 16 arranged around the reflecting mirror 12, and each LED 16 is provided on one surface of the reflecting mirror 12. A concave reflecting surface 14 is formed so as to face the surface.

  The concave reflecting surface 14 is broadly divided and formed by connecting four first to fourth concave reflecting surfaces 14A to 14D vertically and horizontally. Each of the first to fourth concave reflecting surfaces 14A to 14D is formed by providing a parabolic recess on each of the four surfaces of the reflecting mirror 12 divided into four equal parts. And LED16 is opposingly arranged for every 1st-4th concave reflective surface 14A-14D. The reflected light from the first to fourth concave reflecting surfaces 14A to 14D irradiates a rectangular predetermined range (predetermined size) extending in the X direction at a predetermined distance from each other, as shown in FIG. 2B. Thus, irradiation areas 20A to 20D are formed, and the irradiation areas 20A to 20D are overlapped to form one irradiation area 20.

Specifically, the irradiation areas 20A and 20B of the first and second concave reflecting surfaces 14A and 14B arranged side by side on one side of the reflecting mirror 12 irradiate the same irradiation range 21A, respectively. Furthermore, the irradiation areas 20C and 20D of the third and fourth concave reflecting surfaces 14C and 14D respectively irradiate the same irradiation range 21B. Thereby, the illumination intensity in irradiation range 21A, 21B is raised. Further, the irradiation ranges 21A and 21B are arranged so as to be shifted in the Y direction while partially overlapping each other, whereby the irradiation area 20 is expanded in the Y direction. In the dental LED surgical light 1, the X direction is directed to the left and right directions of the patient's face, and the Y direction is directed to the vertical direction of the face, so that the patient's mouth can be well illuminated without illuminating the eyes of the patient. Can do.
Further, each irradiation range 21A, 21B is configured to obtain a shadowless effect. Since the first and second concave reflecting surfaces 14A and 14B and the third and fourth concave reflecting surfaces 14C and 14D have the same configuration, in the following description, the first and second concave reflecting surfaces 14A and 14B are used. This will be described as a representative.

FIG. 4 is a diagram schematically showing the direction of the reflected light on the first and second concave reflecting surfaces 14A and 14B.
The series of concave reflecting surfaces 14 including the first and second concave reflecting surfaces 14A and 14B are formed with shadowless reflecting surfaces 18 at both ends thereof. Each non-shadow reflection surface 18 directs the reflected light 22A of the LED 16 to the central portion O of the irradiation range 21A so that the light rays intersect before reaching the irradiation range 21A to irradiate the central region Ra of the irradiation range 21A. It is the reflective surface provided in. Thereby, a shadowless effect is obtained in the central region Ra.

Further, the first and second concave reflecting surfaces 14A and 14B are respectively provided with a full range irradiation reflecting surface 17 and unevenness preventing reflecting surfaces 19A to 19C in the remaining portions of the shadowless reflecting surface 18. ing.
The entire range irradiation reflecting surface 17 irradiates the entire region Rc of the irradiation range 21 </ b> A with the reflected light 22 </ b> B of the LED 16. In the first and second concave reflecting surfaces 14 </ b> A and 14 </ b> B, the full range irradiation reflecting surface 17 is provided at the front position where the amount of radiated light of the LED 16 is the largest. The reflection surfaces 19A to 19C for preventing unevenness irradiate the left and right half regions Rb including the remainder of the central region Ra with reflected light 22C, 22D, etc., and eliminate the uneven illuminance in the left and right half regions Rb Each region of the non-uniform reflection surfaces 19A to 19C is defined.

  Also in the irradiation range 21B by the third and fourth concave reflecting surfaces 14C and 14D, as in the irradiation range 21A, there is no overall illuminance unevenness, and a shadowless effect is obtained in the central region Ra. These irradiation ranges 21A , 21B is obtained by the shadowless LED unit 10.

The shadowless LED unit 10 is manufactured by assembling the LED 16 to the reflecting mirror 12. Specifically, the plate-like LED mounting plate 30 is screwed and fixed to each of the side surfaces extending in the longitudinal direction of the reflecting mirror 12 at positions facing the first to fourth concave reflecting surfaces 14A to 14D, respectively. The LED 16 is attached to each LED mounting plate 30. At this time, although LED16 can be arrange | positioned facing the 1st-4th concave-surface reflective surfaces 14A-14D by attaching LED16 to the inner surface of the LED attachment plate 30, in this embodiment, it is as follows. That is, as shown in FIG. 3, the LED mounting plate 30 is provided with an LED fixing portion 32 overhanging the concave reflecting surface 14, and the LED 16 is fixed to the LED fixing portion 32 with screws. Thereby, since LED16 radiates | emits light from the position which overhanged each 1st-4th concave reflective surface 14A-14D, compared with the case where LED16 is fixed in the inner surface of LED mounting plate 30, reflection for shadowlessness Since the amount of light incident on the surface 18 can be increased, the shadowless effect can be enhanced.
Moreover, in the shadowless LED unit 10 manufactured in this way, a shadowless effect can be obtained by itself, and therefore when the dental LED shadowless lamp 1 is assembled to the case body 2, the shadowless LED unit 10 is used. Only by fixing the LED unit 10 to the case body 2 as it is, a surgical light is formed.

Here, in order to reduce weight and cost, the reflector 12 is made of a resin molded product as a base material (base material).
Specifically, as shown in FIG. 5, a base material 50 of the reflecting mirror 12 having a concave surface that becomes the first to fourth concave reflecting surfaces 14A to 14D by molding a synthetic resin (see FIG. 6). Is formed (step S1). On each of the concave surfaces of the base material 50, the non-shadow reflection surface 18, the full-range irradiation reflection surface 17, and the non-uniformity reflection surfaces 19A to 19C are also partitioned in the mold forming stage.
In the following description, each of the first to fourth concave reflecting surfaces 14A to 14D, the shadowless reflecting surface 18, the full-range irradiation reflecting surface 17, and the unevenness preventing reflecting surfaces 19A to 19C is particularly described. When there is no need to distinguish between them, it is simply referred to as a “reflecting surface” and denoted by reference numeral 60.

  In the base material 50 after molding, the boundary K between the reflective surfaces 60 among the edges of each reflective surface 60 will be described in detail later, but the roughness at the boundary K at the base material molding stage. The boundary K is made light diffusive. That is, as shown in FIG. 5, a die having a die face that increases the roughness of the boundary K between the reflecting surfaces 60 is designed and manufactured in advance (step S0), and a resin is used using this die. By molding, the roughness of the boundary K in the base material 50 is increased at the stage of molding the base material 50. This eliminates the need for a separate process such as sandblasting the surface of the base material 50 after molding, so that the roughness of the boundary K can be increased easily and accurately.

  Next, as shown in FIG. 5, in order to increase the smoothness of the surface of the base material 50, an undercoat layer 51 (FIG. 6) made of, for example, a silicon-based inorganic thin film is formed on the surface (step S2). A metal material such as aluminum is vapor-deposited on the coat layer 51 to form a reflective layer 52 (FIG. 6) that is much thinner than the undercoat layer 51 (step S3). The reflective layer 52 may be a dielectric multilayer film instead of vapor deposition of a metal film. Thereafter, in order to improve the corrosion resistance and scratch resistance of the reflective layer 52, a topcoat layer 53 (FIG. 6) made of, for example, an inorganic thin film is formed on the reflective layer 52 (step S4). Manufactured.

In this reflecting mirror 12, since the undercoat layer 51 is interposed between the base material 50 and the reflective layer 52, the surface shape of the base material 50 can be mold-molded so as to accurately match the optical design value. If no measures are taken, the shape of the edge 60A of the reflective surface 60 differs from the shape of the edge 50A of the base material 50 due to the influence of the thickness of the undercoat layer 51, as shown in FIG. End up.
In the present embodiment, each of the shadowless reflection surface 18, the full-range irradiation reflection surface 17, and the unevenness prevention reflection surfaces 19A to 19C is defined in the concave surfaces of the first to fourth concave reflection surfaces 14A to 14D. Therefore, at the boundary K between the shadowless reflecting surface 18, the entire range irradiating reflecting surface 17, and the unevenness preventing reflecting surfaces 19A to 19C, as shown in FIG. A step is generated in which the portion 60A is vertically displaced. As described above, the edge shape of the edge 60A of the reflection surface 60 is blunted, and the reflected light M2 is generated in a direction different from the reflected light M1 expected from the optical design value.

The reflected light M2 at the edge 60A of the reflecting surface 60 is originally light that irradiates the edge of the irradiation area of the reflecting surface 60. Therefore, when the reflected light M2 is directed in a direction different from the original, the edge of the irradiation area Blur will occur. In particular, in the dental LED surgical light 1, when the reflected light M2 is directed to the outside of the irradiation area, the irradiation area is widened, and the irradiation light easily reaches the eyes of the patient.
Note that the problem at the edge 60A of the reflection surface 60 is not limited to the case where the reflection surfaces 60 are connected with a step, and for example, as shown in FIG. This is a problem that generally arises when two reflecting surfaces 60 are connected at the boundary K, such as when they are arranged in a line.

  Therefore, in the present embodiment, as described above, the roughness of the edge 60A of the reflecting surface 60 is increased by increasing the roughness of the edge 50A in advance at the stage of molding the base material 50. Thereby, as shown in FIG. 6, the reflected light M2 at the edge 60A of the reflecting surface 60 is scattered by diffusion and directed in a random direction. For this reason, since the reflected light M2 is diffused widely with reference to the edge in the irradiation area, the amount of light per unit area of the reflected light M2 can be suppressed, and the occurrence of blurring due to the reflected light M2 can be made inconspicuous.

  Here, the roughness of the edge portion 60A over the entire circumference of each reflecting surface 60 may be increased, but for the portion where the reflected light M2 of the edge portion 60A is not extracted to the outside, processing for increasing the roughness is performed. There is no need to apply. That is, in this embodiment, as shown in FIG. 6, the light P of the LED 16 is irradiated, and the reflected light M2 at the edge 60A is extracted outside without being shielded by the wall surface of the case body 2. The roughness is increased only for the edge portion 60A.

  FIG. 8 is a diagram showing an example of the characteristics of the shadowless LED unit 10, FIG. 8A shows the illuminance distribution in the irradiation area 21, and FIG. 8B shows the irradiation area 21 in the X direction (see FIG. 8). 2 (B)) shows the illuminance distribution of the cross section cut, and FIG. 8 (C) shows the illuminance distribution of the cross section obtained by cutting the irradiation area 21 in the Y direction (FIG. 2 (B)). The dimensions of the concave reflecting surface 14 of the reflecting mirror 12 are 180 mm in the X direction and 90 mm in the Y direction (each of the first to fourth concave reflecting surfaces 14A to 14D is 90 mm in the X direction and 45 mm in the Y direction). The position of the area 21 is set to a position separated from the shadowless LED unit 10 by a distance of 700 mm directly below.

  As shown in these drawings, according to the shadowless LED unit 10, the substantially rectangular irradiation area 21 having a length (Y direction) of about 80 mm and a width (X direction) of about 200 mm due to the reflected light from each reflection surface 60. Is obtained. Moreover, about the X direction of the irradiation area 21, it turns out that the substantially uniform illumination intensity distribution is obtained by the reflective surface 17 for whole range irradiation, and the reflective surfaces 19A-19C for unevenness prevention. Further, in the Y direction of the irradiation area 21 (that is, the direction from the mouth toward the eyes), the illuminance at a location outside this range is reduced while securing an illuminance of about 30000 lux in a range of ± 40 mm. .

  In particular, in the shadowless LED unit 10, the roughness of the edge 60 </ b> A of each reflecting surface 60 of the reflecting mirror 12 is increased, and the reflected light M <b> 2 at the edge 60 </ b> A is reflected around the irradiation area 21 (FIG. 8A). Since the amount of light per unit area of the reflected light M2 is very low by being diffused over a wide range, the roughness of the edge 60A of each reflecting surface 60 is not increased at the edge E of the irradiation area 21. Compared to (indicated by the dotted lines in FIGS. 8A and 8B), the contrast can be made clearer, and a sharp edge E can be obtained. As a result, the amount of light reaching the patient's eyes can be reduced, and only the mouth can be illuminated with high illuminance.

  As described above, according to the present embodiment, the reflecting mirror 12 included in the shadowless LED unit 10 is configured to increase the roughness of the surface of the edge 60A of the reflecting surface 60. Therefore, the edge 60A of the reflecting surface 60 The reflected light M2 is diffused over a wide range, and the amount of light per unit area in the irradiation area 21 becomes very small. Thereby, since the light quantity which irradiates the edge E of the irradiation area 21 is very reduced, or the edge is not irradiated, blurring of the edge E of the irradiation area 21 is suppressed, and a sharp edge E can be obtained. .

Further, according to the present embodiment, the reflecting mirror 12 is configured by connecting a plurality of reflecting surfaces 60 with overlapping irradiation ranges, and the surface roughness of the edge portion 60 </ b> A corresponding to the boundary K of each reflecting surface 60 is increased. According to this configuration, even if the light amount of the reflected light M2 at the edge portion 60A of the reflective surface 60 decreases in the irradiation area, the light amounts of the reflected light M2 in the irradiation area 21 are overlapped by overlapping the irradiation ranges of the respective reflective surfaces 60. Can compensate for the decline.
In addition, if the range which raises surface roughness in 60 A of edge parts is enlarged, since an irradiation area will reduce correspondingly, it will become a factor of the illumination intensity nonuniformity in the overlap part of the irradiation range of each reflective surface 60. Therefore, it is desirable that the range in which the surface roughness is increased in the edge portion 60A is set so as not to cause uneven illumination.

In addition, according to the present embodiment, the base material 50 in which the roughness of the edge portion 60 </ b> A is increased in advance is formed, and the undercoat layer 51 and the reflective layer 52 are formed on the surface of the base material 50. As a result, after the reflecting mirror 12 is manufactured, it is not necessary to perform another process such as increasing the surface roughness of the edge 60A by sandblasting or the like, so that the manufacturing becomes easy.
In particular, by processing the shape of the die face of the mold for molding the base material 50 to increase the roughness of the edge portion 60A, the roughness of the edge portion 60A can be accurately increased.

  The above-described embodiments merely show one aspect of the present invention, and can be arbitrarily modified and applied within the scope of the present invention.

For example, in the above-described embodiment, the case where a plurality of reflecting surfaces 60 are connected to the reflecting mirror 12 is illustrated, but the present invention is not limited to this, and a single reflecting surface 60 may be used.
In addition, for example, the configuration in which the roughness of the edge 60A of the reflecting surface 60 is increased to diffuse the reflected light M2 over a wide range is not limited to this, but the configuration is not limited to this, and the reflected light M2 is not generated by making the edge 60A non-reflective. Also good. Specifically, a shielding member is provided so as to cover the edge 60A of the reflection surface 60, or the reflection layer 52 is not formed on the edge 60A by masking the edge 60A of the reflection surface 60 when forming the reflection layer 52. You may do it.

  In addition, for example, in the above-described embodiment, a surgical light is illustrated as an example of a lighting fixture including the reflecting mirror 12. However, the present invention is not limited thereto, and the present invention suppresses the amount of light other than the irradiation area 21, and the irradiation area 21. For example, it can be applied to an arbitrary lighting device such as a reading lamp in a bedroom or a hospital where it is desired to sharpen the edge E of the lamp.

DESCRIPTION OF SYMBOLS 1 Dental LED shadowless lamp 2 Case body M1, M2 Reflected light 10 Shadowless LED unit 12 Reflective mirror 14, 14A-14D Concave reflective surface (reflective surface)
16 LED (point light source)
17 Reflective surface for full range irradiation (reflective surface)
18 Shadowless reflective surface (reflective surface)
19A Reflective surface for prevention (reflective surface)
30 LED mounting plate 32 LED fixing part 50 base material 50A edge 51 undercoat layer 52 reflective layer 53 topcoat layer 60 reflective surface 60A edge K boundary

Claims (2)

Comprising a plurality continuously provided the reflector with a concave reflecting surface having a plurality of reflecting surfaces, the LED is arranged on each concave reflecting surface, a plurality of the concave reflective surface, overlapping irradiation area forms one illumination area The reflection surfaces at both ends of the concave reflection surface that are continuously provided are used as shadowless reflection surfaces that direct the light beams of the plurality of LEDs toward the center of the one irradiation area, and In the LED unit fixed to the bottom ,
The plurality of LEDs are arranged side by side at a predetermined interval,
The reflecting mirror has a substantially rectangular parallelepiped shape in which a concave reflecting surface is continuously provided for each LED on one surface facing the LED,
An LED characterized in that a shielding member is provided in a portion that reflects toward the edge of the one irradiation area in the optical design and is made non-reflective at a boundary between the reflecting surfaces of the concave reflecting surface. unit. Comprising a plurality continuously provided the reflector with a concave reflecting surface having a plurality of reflecting surfaces, the LED is arranged on each concave reflecting surface, a plurality of the concave reflective surface, overlapping irradiation area forms one illumination area The reflection surfaces at both ends of the concave reflection surface that are continuously provided are used as shadowless reflection surfaces that direct the light beams of the plurality of LEDs toward the center of the one irradiation area, and In the LED unit fixed to the bottom ,
The plurality of LEDs are arranged side by side at a predetermined interval,
The reflecting mirror has a substantially rectangular parallelepiped shape in which a concave reflecting surface is continuously provided for each LED on one surface facing the LED,
The concave reflecting surface is formed by forming a reflecting layer on the base material surface,
The boundary between the reflecting surfaces of the concave reflecting surface, wherein the reflecting layer is formed other than the portion that reflects toward the edge of the one irradiation area in the optical design, and the portion is made non-reflecting. LED unit to do.

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