JP2015022986A - Light source device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light source device capable of emitting light in desired illumination distribution.SOLUTION: A light source device includes: a plurality of LEDs 21 for emitting light frontward; a rod lens provided so as to face a front side of the LEDs 21; and a case 10 for accommodating the LEDs 21 and the rod lens and having an opening for allowing the light emitted from the LEDs and transmitted through the rod lens to pass. The LEDs 21 include: first LEDs 21x arranged in parallel along an X direction; and second LEDs 21y arranged in parallel along the X direction. Between the first and second LEDs, a light shielding mask 50 is provided so as to stride over front surfaces 21xa, 21ya of these, and by this light shielding mask 50, spreading of light from the first and second LEDs 21x, 21y can be suppressed.

Description

  The present invention relates to a light source device that emits light such as ultraviolet light.

  As a conventional light source device, for example, one described in Patent Document 1 below is known. In such a light source device, LEDs that emit visible light are arranged in front, a translucent member made of acrylic is arranged on the front side, and a space between the LED and the translucent member is silicon. It is sealed with a transparent resin. In this light source device, visible light from the LED is emitted through the transparent resin and the translucent member.

JP 2008-186914 A

  Here, in the light source device as described above, light is usually emitted to the outside as diffused light that diffuses radially, and the illuminance distribution has an illuminance distribution such as a Gaussian distribution. In this regard, in light source devices in recent years, when application to various fields is increasingly progressing, a device capable of emitting light with a desired illuminance distribution such as a uniform illuminance distribution is required for a predetermined irradiation area. There is.

  Then, this invention makes it a subject to provide the light source device which can radiate | emit light with a desired illumination intensity distribution with respect to a predetermined irradiation area.

  In order to solve the above problems, a light source device according to the present invention includes a plurality of light emitting elements that emit light toward the front, a light transmitting member provided to face the front side of the light emitting elements, a light emitting element, and And a case having an opening through which light emitted from the light emitting element and transmitted through the light transmitting member is passed, wherein the light emitting element is arranged in parallel along a predetermined direction. 1 light emitting element and 1 or several 2nd light emitting element arranged in parallel along the predetermined direction at least, Between the 1st and 2nd light emitting elements, the front surface of the said 1st and 2nd light emitting elements A shielding member is provided so as to straddle.

  In this light source device, between the first and second light emitting elements, the shielding member provided so as to straddle these front surfaces can appropriately suppress the spread of light from the first and second light emitting elements, As a result, it is possible to emit light with a desired illuminance distribution with respect to a predetermined irradiation area. For example, it is possible to emit light to the outside with an illuminance distribution that is uniform and conforms to the outer shape of the light exit surface (similar shape). If the light exit surface is rectangular, a rectangular beam profile is preferable. Can be obtained.

  Moreover, it is preferable to further include a frame portion provided so as to cover the outer edge portion on the front surface of the light transmitting member. In this case, the spread of the light transmitted through the light transmitting member can be suppressed by the frame portion, and also in this respect, the light can be emitted to the outside with an illuminance distribution that is uniform and matched to the outer shape of the light emitting surface Become.

  Further, as a configuration that preferably exhibits the above-described effects, the frame portion may be provided at the edge of the opening in the case, and the front surface of the light transmission member may be in contact with the frame portion. Further, the front surface of the light emitting element may be in contact with the light transmitting member via a shielding member.

  ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to provide the light source device which can radiate | emit light with desired illuminance distribution.

It is a perspective view which shows the light source device which concerns on one Embodiment from the front side. It is a disassembled perspective view of the light source device of FIG. It is a rear view which shows the case front side of the light source device of FIG. It is a front view which shows the LED board of the light source device of FIG. It is a figure which expands and shows the cross section which follows the VV line | wire of FIG. (A) is a schematic view seen from the X direction for explaining light emission in the light source device of FIG. 1, and (b) is a schematic view seen from the Y direction for explaining light emission in the light source device of FIG. FIG. It is a schematic diagram which shows the beam profile of the light source device of FIG. It is the schematic diagram seen from the X direction for demonstrating the emission of the light in the light source device which concerns on other embodiment. It is the schematic diagram seen from the X direction for demonstrating the emission of the light in the light source device which concerns on reference embodiment. It is a schematic diagram for demonstrating the example of the positional relationship in the light source device of FIG.

  DESCRIPTION OF EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. In the following description, the same or corresponding elements are denoted by the same reference numerals, and redundant description is omitted. Moreover, the light emission direction of LED (light emitting element) is made into the front, and the other side is demonstrated as back.

  FIG. 1 is a perspective view showing a light source device according to an embodiment from the front side, and FIG. 2 is an exploded perspective view of the light source device of FIG. As shown in FIGS. 1 and 2, the light source device 100 of the present embodiment irradiates light such as ultraviolet light and performs, for example, resin curing, ink drying, and the like. The light source device 100 is capable of emitting light with a desired illuminance distribution with respect to a predetermined irradiation area. In the following, as an example, the light source device 100 can emit light with a uniform illuminance distribution. Will be described.

  The light source device 100 includes a case 10 constituting an outer periphery, an LED substrate 20 having a plurality of LEDs (Light Emitting Diodes) 21, and a rod lens (light transmissive member) having a rectangular parallelepiped outer shape that transmits light from the LEDs 21. 30 and a heat sink 40 that dissipates heat from the LED substrate 20. The light exit surface of the rod lens 30 has a rectangular shape. The light source device 100 here has, for example, a rectangular parallelepiped outer shape having an X-direction dimension of 50 mm, a Y-direction dimension of 50 mm in width, and a front-rear direction dimension of 45 mm.

  FIG. 3 is a rear view showing the case front side of the light source device of FIG. 1. As shown in FIGS. 2 and 3, the case 10 has a rectangular parallelepiped case front side 11 and a plate-like case rear side 12, which are fixed to each other with screws or the like. The front surface 11a of the case front side 11 is formed with an opening 13 having a rectangular shape elongated in the X direction when viewed from the front. The opening 13 constitutes an emission window that emits light to the outside, and has a rectangular light emission surface that allows light emitted from the LED 21 and transmitted through the rod lens 30 to pass therethrough. The dimensions of the opening 13 here are 34 mm in the longitudinal direction and 19 mm in the lateral direction. A frame portion 60 is formed at the edge of the opening 13 (details will be described later).

  On the rear surface 11b of the case front side 11, an LED substrate housing portion 14 is formed as a recess that opens to the rear and one side in the Y direction (the lower side in the drawing). In addition, the LED board accommodation part 14 here has the depth of the one side part of the Y direction in order to make it respond | correspond to the height of the below-mentioned connector 23 in the LED board 20. A rod lens housing portion 15, which is a through hole communicating with the opening 13, is formed on the bottom surface of the LED substrate housing portion 14 so as to fit and house the rod lens 30.

  FIG. 4 is a front view showing an LED substrate of the light source device of FIG. As shown in FIG. 4, the LED substrate 20 has a rectangular plate-like substrate 22 constituting a predetermined circuit, and a plurality of LEDs 21 are arranged in parallel on the front surface 22 a of the substrate 22. The LED 21 is an ultraviolet light emitting chip type light emitting element in which a semiconductor crystal is housed in a casing having a rectangular parallelepiped outer shape and sealed with a glass plate, and emits light such as high output ultraviolet light forward. The LED 11 has a square shape when viewed from the front surface 12a, and has a width of, for example, 7 mm long × 7 mm wide.

  The LEDs 21 here are provided in two rows in the Y direction and five in the X direction (a total of 10). That is, the LEDs 21 are juxtaposed along the X direction so as to be close to each other and the plurality of first LEDs (first light emitting elements) 21x arranged along the X direction (predetermined direction) so as to be close to each other. A plurality of second LEDs (second light emitting elements) 21y, and these first and second LEDs 21x and 21y are adjacent (or close) to each other with a predetermined pitch (predetermined distance) apart from each other in the Y direction. .

  The predetermined pitch of the first and second LEDs 21x and 21y here is set so as to be emitted from the light source device 100 with a uniform illuminance distribution (also simply referred to as “uniform illuminance distribution”) to the irradiation area. For example, in the present embodiment, the thickness is set to 15 mm as preferable from the relationship with the thickness (dimension in the front-rear direction) of the rod lens 30. On the other hand, the interval between the plurality of LEDs 21 in the X direction is set to be narrower than the predetermined pitch, for example, 7 mm.

  Further, on the front surface 22 a of the substrate 22, a connector 23 for electrically connecting to the substrate 22 is provided on one side (the lower side in the drawing) of the LED 21 in the Y direction. Such an LED substrate 20 is fixed to the front surface 12a of the case rear side 12 with screws or the like.

  FIG. 5 is an enlarged view showing a cross section taken along the line V-V in FIG. 1. As shown in FIGS. 2 and 5, the rod lens 30 is a rectangular light transmission member having a rectangular parallelepiped shape elongated in the X direction, and is formed to include quartz. The rod lens 30 has a function as a lens or a mixing member.

  The rod lens 30 is provided so as to face the front side of the LED 21, and repeatedly and totally reflects the light emitted from the LED 21, and makes the light amount uniform while increasing the peak light amount of the light. The outer surface of the rod lens 30 is mirror-polished. The thickness of the rod lens 30 is set to a predetermined length set so as to be emitted from the light source device 100 with a uniform illuminance distribution. For example, the relationship with the distance (pitch) between the first and second LEDs 21x and 21y. Therefore, it is preferably 15 mm in this embodiment.

  Such a rod lens 30 is inserted and fitted into the rod lens accommodating portion 15 on the case front side 11 from the rear. Thereby, the rod lens 30 is disposed so that the front surface 30a abuts on the frame portion 60 of the case 10 and the rear surface 30b abuts on the front surface 21a of the LED 21 (see FIG. 7). As a result, the LED 21 faces the outside from the opening 13 through the rod lens 30.

  Returning to FIG. 1, the heat sink 40 includes a plurality of fins 41 having a rectangular flat plate shape. The plurality of fins 41 are erected on the rear surface 12b of the case rear side 12 so as to be arranged with a gap.

  Here, the light source device 100 of the present embodiment includes a light shielding mask (shielding member) 50 provided between the first and second light emitting elements, as shown in FIGS. The light shielding mask 50 has a shielding property for shielding light from the LED 21 and is made of, for example, aluminum. The light shielding mask 50 has a long sheet shape or plate shape in the X direction. Here, the light shielding mask 50 has a longitudinal direction of 35 mm, a lateral direction of 11 mm, and a thickness of 0.1 mm.

  The light shielding mask 50 is provided so as to straddle the front surfaces 21xa and 21ya as irradiation surfaces of the first and second LEDs 21x and 21y. That is, the light shielding mask 50 is disposed so as to be bridged between the front surfaces 21xa and 21ya. Specifically, the light shielding mask 50 covers a part of the front side 21xa of the plurality of first LEDs 21x on the second LED 21y side (lower side) and a part of the front side 21ya of the plurality of second LEDs 21y on the second LED 21y side (upper side). It is provided to cover.

  Such a light shielding mask 50 is fixed and attached to the case front side 11 with screws 51. Accordingly, the light shielding mask 50 is in contact with the front surface 21 a of the LED 21 and is interposed between the LED 21 and the rod lens 30 in a state of being in contact with the rear surface 30 b of the rod lens 30. In other words, the front surface 21 a of the LED 21 is brought into contact with the rod lens 30 through the light shielding mask 50.

  In addition, the light source device 100 of the present embodiment includes a frame portion 60 provided so as to cover the outer edge portion 30a1 of the front surface 30a of the rod lens 30. The frame part 60 constitutes the lens frame of the rod lens 30 and is provided at the edge of the opening 13 on the case front side 11. That is, the frame portion 60 is provided so as to protrude inward at the front end of the inner surface of the rod lens housing portion 15. The rear surface 60b of the frame portion 60 is in contact with the front surface 30a with the rod lens 30 being abutted against it.

  In the light source device 100 configured as described above, for example, power is supplied to each LED 21 of the LED substrate 20 via the connector 23, and light is emitted forward from these LEDs 21. This light is guided to the rod lens 30 and repeats total reflection in the rod lens 30, and the peak light quantity is increased and uniformed, and then output forward from the opening 13 on the case front side 11 as output light, The irradiated object is irradiated.

  At this time, as shown in FIG. 6A, the light from the first LED 21x spreads to the second LED 21y side by the light shielding mask 50 provided across the front surfaces 21xa and 21ya between the first and second LEDs 21x and 21y. Can be masked, and the light from the second LED 21y can be masked from spreading toward the first LED 21x. As a result, the light from the first and second LEDs 21x and 21y is prevented from spreading, the amount of light spreading from the light exit surface formed by the opening 13 is reduced, and the irradiation area at a position a predetermined distance ahead is reduced. It is possible to emit the light to the outside (collimated emission) in a state of being collimated to form a rectangular light beam. Therefore, according to the present embodiment, the light can be emitted to the outside with a rectangular shape and uniform illuminance distribution.

  In addition, as shown in FIGS. 6A and 6B, the light transmitted through the rod lens 30 can be emitted to the outside while being prevented from spreading by the frame portion 60. Thereby, the light can be made into a rectangular shape which is the shape of the light emitting surface, and the illuminance distribution can be made more uniform.

  FIG. 7 is a schematic diagram showing a beam profile of the light source device of FIG. In the figure, the X position means the position in the X direction, and 0 means the center of the opening 13 in the X direction. The Y position means the position in the Y direction, and 0 means the center of the opening 13 in the Y direction. As shown in FIG. 7, in this embodiment, regarding the illuminance (intensity), rectangular beam profiles Px and Py can be obtained in both the X direction and the Y direction, and the illuminance distribution can be made uniform. Yes.

  FIG. 8 is a schematic diagram viewed from the X direction for explaining light emission in a light source device according to another embodiment. As illustrated in FIG. 8, the light source device 100 may not include the frame portion 60. Even in this case, as shown in the figure, the light can be emitted to the outside with a uniform illuminance distribution having a rectangular shape.

  FIG. 9 is a schematic view seen from the X direction for explaining light emission in the light source device according to the reference embodiment. As shown in FIG. 9A, in the light source device that does not include the light shielding mask 50 and the frame portion 60, the light from the first and second LEDs 21x and 21y spreads from the light exit surface and is easily emitted to the outside as diffused light. It can be seen that it is difficult to obtain uniform light in a rectangular shape with respect to the irradiation area located in front of the predetermined distance. That is, an unintended irradiation area with a low light amount is generated around the desired irradiation area.

  Further, as shown in FIG. 9B, in a light source device that does not include the light shielding mask 50 and the frame portion 60, a rod lens having a thickness that is ½ of the thickness of the rod lens 30 instead of the rod lens 30. When 30 'is used, it turns out that the light from 1st and 2nd LED21x, 21y spreads from a light-projection surface, and is radiate | emitted outside. That is, it can be seen that the thickness of the rod lens 30 also includes an element that affects the above-described effect of emitting the light with a uniform illuminance distribution having a rectangular shape.

  On the other hand, the thickness of the rod lens 30 of the present embodiment is set to a predetermined length so as to be emitted with a uniform illuminance distribution having a rectangular shape matching the shape of the light emitting surface. The embodiment is effective in realizing the above-described effects.

  Further, as shown in FIG. 9C, in the light source device that does not include the light shielding mask 50 and the frame portion 60, when the pitch between the first and second LEDs 21x and 21y is narrower than the predetermined pitch, the first and first It can be seen that the light from the 2LEDs 21x and 21y spreads from the light emitting surface and is emitted to the outside. That is, it can be seen that the pitch between the first and second LEDs 21x and 21y also includes an element that affects the above-described effect.

  On the other hand, as described above, the pitch between the first and second LEDs 21x and 21y in the present embodiment is set to a predetermined pitch that is emitted with a uniform illuminance distribution having a rectangular shape that matches the shape of the light emitting surface. In this respect as well, the present embodiment is effective for realizing the above-described effects.

FIG. 10 is a schematic diagram for explaining an example of the positional relationship in the light source device of FIG.
In the present embodiment, the following relationship is provided to emit light with a uniform illuminance distribution having a rectangular shape that matches the shape of the light emitting surface with respect to the irradiation area on the irradiation object. That is, with reference to FIG. 10, when the pitch of the LEDs 21x and 21y is P and the thickness of the rod lens 30 is D, the thickness D has the relationship of the following formula (1). The constant α is preferably 0.8 to 1.2, and is 1.0 here.
D = αP (α: constant) (1)

Further, when a desired irradiation area on the irradiation object, that is, a necessary irradiation width is x and an irradiation window width of each LED 21 is L, the pitch P has a relationship of the following expression (2). . The constant β is preferably 0.8 to 1.2, and the constant γ is preferably 0.5 to 2.0.
P = βx−γL (β, γ: constant) (2)

Further, when the light beam angle irradiated by masking the LED 21 with the light shielding mask 50 is θ and the irradiation distance to the irradiated object is y, the light beam angle θ has the relationship of the following expression (3). Yes. That is, the light shielding mask 50 is provided so as to have a light beam angle according to the following expression (3). Incidentally, the width W of the rod lens 30 here has a relationship of “W = βx” and “W = P + γL”.
tan θ = (P + x) / (2 (y + αP)) (3)

  The preferred embodiments of the present invention have been described above. However, the present invention is not limited to the above-described embodiments. The present invention is modified without departing from the gist described in each claim or applied to other embodiments. It may be a thing.

  For example, in the above embodiment, the LEDs 21 are arranged in two rows of the first and second LEDs 21x and 22y, and the light shielding mask 50 is provided between the first and second LEDs 21x and 22y. However, the present invention is not limited to this. is not. The point is that it includes at least one or a plurality of first light emitting elements arranged in parallel along a predetermined direction and one or a plurality of second light emitting elements arranged in parallel along a predetermined direction. It is only necessary to have a feature that a shielding member is provided between the two light emitting elements so as to straddle the front surfaces of the first and second light emitting elements, and this feature includes at least the configuration exemplified below. .

  That is, for example, the LEDs 21 may be arranged in three or more rows, and in this case, the light shielding mask 50 is provided in at least one of the plurality of LED 21 rows. In this case, the light shielding mask 50 may be provided so as to cover the entire region between the LED 21 rows, or the light shielding mask 50 may be provided so as to partially cover the LED 2 rows. Further, the light shielding mask 50 may be divided into a plurality of parts, or may be integrally formed.

  The light shielding mask 50 may have an opening, and the LED 21 may be exposed from the opening. In other words, an opening may be provided in a region corresponding to the LED 21 in the light shielding mask 50 so that the LED 21 is not hidden behind the light shielding mask 50. In this case, it is possible to suppress the light from the LED 21 from being completely blocked by the light blocking mask 50 and maintain the integrated light quantity. Moreover, the number of 1st and 2nd LED21x, 22y is not limited, and each should just be 1 or multiple. For example, when the LEDs 21 are arranged in a plurality of rows, each LED 21 row may have the same number of LEDs 21 or a different number of LEDs 21.

  Moreover, in the said embodiment, although the square rod lens 30 was provided, the external shape of the rod lens 30 is not limited. Furthermore, the light transmissive member is not limited to the rod lens 30, and other light transmissive members may be used as long as they are members that transmit light.

  Moreover, in the said embodiment, although demonstrated as what can be radiate | emitted by the rectangular uniform illumination intensity distribution when a light-projection surface is a rectangular shape, it is not limited to this, According to the shape of a light-projection surface (similarity) It can be emitted with a uniform illuminance distribution, for example, when the light exit surface is square, circle, ellipse, oval, flat circle, square circle, square, circle, ellipse, oval, flat circle, The light can be emitted with a uniform circular illuminance distribution. Furthermore, the present invention can not only emit light with a uniform illuminance distribution but also emit light with a desired illuminance distribution. For example, by providing an opening (non-shielding portion) in the light shielding mask 50, the value of the region where the opening is formed is reduced while the value of the region where the opening is not formed in the beam profile is made uniform. be able to.

  Moreover, the following structure is mentioned as another specific structure of the said embodiment, for example. That is, N (N: integer) first and second LEDs 21x and 22y are provided so as to be arranged in the X direction from a predetermined position in the X direction, and a light shielding mask 50 is provided between them. At the same time, M third LEDs (M: integer) are provided between the first and second LEDs 21x and 22y so as to be arranged in the X direction from the predetermined position in the X direction. The light-shielding mask 50 includes a configuration in which an opening is formed at a position corresponding to the third LED so that light from the third LED is not blocked. In this case, it is possible to obtain a beam profile in which the edge on one end side of the rectangular shape is gently inclined (blunted). In this case, the amount of light can be improved by the third LED. N may be 3 or more, and M may be 2 or more (provided that M <N).

  Moreover, although the said embodiment was provided with LED21 as a light emitting element, it may replace with this or may add another light emitting element. Moreover, although the said embodiment provided the light shielding mask 50 as a shielding member, it is not limited to this, The shielding member of various shapes and materials can be used if it can shield light (light shielding).

  In the above embodiment, the beam profile can be adjusted as desired by changing the size of the rod lens 30. For example, instead of the rod lens 30, by using a long rod lens in which at least one of one end side and the other end side in the X direction (longitudinal direction) of the rod lens 30 is extended, one end side in the rectangular beam profile is used. And at least one edge on the other end side can be adjusted to be gently inclined (dull). Incidentally, as the extension amount of the rod lens 30 is increased, the degree of inclination (the degree of dullness) of the edge of the beam profile can be increased.

  DESCRIPTION OF SYMBOLS 10 ... Case, 13 ... Opening, 21 ... LED (light emitting element), 21x ... 1st LED (1st light emitting element), 21xa ... Front side of 1st LED (front side of 1st light emitting element), 21y ... 2nd LED (2nd light emission) Element), 21ya: front surface of second LED (front surface of second light emitting element), 30: rod lens (light transmitting member), 30a: front surface of rod lens (front surface of light transmitting member), 50: light shielding mask (shielding member) , 60 ... frame part, 100 ... light source device.

Claims (4)

A plurality of light emitting elements that emit light toward the front;
A light transmissive member provided to face the front side of the light emitting element;
A case having an opening for accommodating the light emitting element and the light transmitting member and allowing the light emitted from the light emitting element to pass through the light transmitting member;
The light emitting element is
One or a plurality of first light emitting elements arranged in parallel along a predetermined direction;
Including at least one or a plurality of second light emitting elements arranged in parallel along the predetermined direction,
Between the said 1st and 2nd light emitting elements, the shielding member is provided so that the front surface of the said 1st and 2nd light emitting elements may be straddled, The light source device characterized by the above-mentioned.   The light source device according to claim 1, further comprising a frame portion provided so as to cover an outer edge portion on a front surface of the light transmission member. The frame portion is provided at the edge of the opening in the case,
The light source device according to claim 2, wherein a front surface of the light transmission member is in contact with the frame portion.   The light source device according to claim 1, wherein a front surface of the light emitting element is in contact with the light transmitting member via the shielding member.

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