JP7287491B2 - Light source device - Google Patents

Description

The present invention relates to a light source device.

In recent years, the light sources used in lighting equipment have changed from incandescent lamps and mercury lamps to semiconductor light sources such as LEDs and LDs that consume less power and have a longer life than these lamps, and fluorescent light sources that use fluorescent light excited by semiconductor light sources. replacement is in progress.

Conventionally, as means for increasing the luminance of light emitted from a light source, there has been known a method in which part of the light emitted from the light source is reflected back toward the light source to increase the luminance of the light emitted in a specific direction. Here, the luminance represents the amount of luminous flux per unit solid angle per unit area in the light emitting portion of the light source.

In Patent Document 1 below, a luminescent spot of a discharge lamp is positioned at the center of curvature of a reflector having a spherical inner surface, and light emitted from the luminescent spot toward the reflector is reflected by the reflector and returns to the luminescent spot. A light source device is described.

JP 2006-301152 A JP 2009-158309 A WO2018/043557

As described above, as a means for increasing the brightness of the light source, a configuration is being studied in which part of the light emitted from the light source is reflected back toward the light source. In addition, as described in Patent Document 1, it is theoretically possible to return all of the light emitted from the light emitting point (bright point) of the discharge lamp back to the light emitting point by the spherical reflecting mirror. be.

On the other hand, as described in Patent Document 2 and Patent Document 3, it is difficult to control emitted light from a light source section having a light emitting region 201 that is spread out. FIG. 18 is a schematic cross-sectional view of the hemispherical mirror 200 cut along a plane including the center C1. As shown in FIG. 18, light emitted from an arbitrary point within the light emitting region 201 except for the center C1 is reflected by the mirror 200, and the region forms a chord of a semicircle according to each emission angle. It diverges to the whole R1.

Therefore, when the light emitted from the light emitting surface is reflected by a spherical reflecting mirror, it is difficult to return all the reflected light to the light emitting surface. It was difficult to increase the brightness.

SUMMARY OF THE INVENTION In view of the above problems, it is an object of the present invention to provide a light source device capable of increasing the utilization efficiency of light emitted from a light-emitting body and increasing the brightness in the area from which the light is emitted.

The light source device of the present invention is
a first reflecting portion having a concave reflecting surface along at least a portion of a body of revolution formed by rotating a semi-ellipse with the major axis of the ellipse as the chord, with the minor axis of the ellipse as the axis of rotation;
a light extraction portion that emits light to the outside of the first reflection portion;
An area surrounded by a closed curve defined by the trajectory of the focal point of the ellipse when rotated about the short axis is defined as a specific area, and light is emitted from the specific area toward the first reflecting section. or a light emitting body constituting a light supply surface that emits light by light reflection,
The light emitting body is
a light emitter that produces light emitted from the light-providing surface;
and a second reflecting portion that re-reflects the light that has been reflected by the first reflecting portion and travels toward the specific region from the specific region toward the first reflecting portion.

The rotating-body-shaped first reflecting portion can reflect the light emitted from the specific region and traveling toward the first reflecting portion so as to return to the specific region. In other words, with the above configuration, of the light emitted from the light emitting body, the light traveling toward the light extraction portion is emitted to the outside of the light source device as it is, and the light traveling toward the first reflecting portion. is reflected by the first reflecting portion and travels toward the specific area again. The shape of the rotating body and the specific region will be described later in the explanation of the first embodiment of "Mode for Carrying out the Invention".

Further, the light emitting body is formed with a second reflecting part, whereby the light reflected by the first reflecting part and proceeding toward the light emitting body is re-reflected toward the specific area. In other words, the light that is emitted from the light emitting body and does not directly proceed to the light extraction part is repeatedly reflected between the first reflecting part and the second reflecting part provided in the light emitting body, and eventually reaches the light source from the light extraction part. Radiates outward from the device.

Therefore, according to the light source device having the above configuration, almost all of the light emitted from the light emitting body is emitted from the light extraction portion toward the outside of the light source device. use efficiency is improved. Then, a light source device with expected brightness in the light extraction portion is realized. Note that the size of the specific region can be arbitrarily set by adjusting the ratio of the minor axis to the major axis of the ellipse to be rotated.

In the above light source device,
The light emitting body may have the light supply surface arranged so as to substantially coincide with the specific region in the minor axis direction.

With the above configuration, of the light emitted from the light supply surface of the light emitting body, the light traveling toward the first reflecting part is reflected between the first reflecting part and the second reflecting part of the light emitting body. The light is repeatedly reflected in between, and eventually radiates from the light extraction portion toward the outside of the light source device. Note that "substantially coincides with the specific region in the short axis direction" means that the light supply surface and the specific region are arranged on the same plane when the light supply surface and the specific region are completely coincident with each other in the short axis direction. Of course, the light supply surface 10A may be slightly spaced from the specific area Fa, including cases within ±10% of the minor axis radius of the first reflecting portion.

In the above light source device,
The first reflecting portion is a wavelength selection mirror that reflects light in a partial wavelength band of the light emitted from the specific region and traveling toward the first reflecting portion toward the specific region. It doesn't matter if it is.

Further, the light source device
A light absorbing portion that absorbs light transmitted through the first reflecting portion may be provided on the opposite side of the reflecting surface of the first reflecting portion. Furthermore, the material forming the reflecting portion itself may be a light absorbing portion that absorbs light.

In the present specification, "reflecting light in a part of the wavelength band" means reflecting light in a specific wavelength band and not only not reflecting other light at all, but also having an extremely low reflectance. Including. And, although it depends on the wavelength range, the reflectance is, for example, 30% or less, more preferably 20% or less, for light in the infrared region.

The first reflecting portion and the second reflecting portion each reflect the light incident on the reflecting surface, absorb the light slightly, and generate heat according to the amount of the absorbed light. That is, part of the light emitted from the light emitting body and repeatedly reflected between the first reflecting portion and the second reflecting portion is gradually absorbed by each reflecting portion until it reaches the light extraction portion. is converted into heat. The heat generated by each reflecting portion increases the temperature inside the light source device.

When the temperature in the light source device rises, the luminous efficiency and conversion efficiency of the light sources such as LEDs, LDs, and fluorescent light sources mounted as light emitters in the light source device decrease. Furthermore, in a configuration in which the light emitting surface of these light sources is used as the second reflecting portion, the luminous body itself generates heat, resulting in a rapid decrease in luminous efficiency and conversion efficiency.

Here, generally, light emitted from all light sources does not show intensity only at a specific wavelength, but shows a spectrum with a certain width. For this reason, the light emitted from the light source device can be divided into light in a wavelength band that can be used as a light source and excitation light, and light that cannot be used as a light source or excitation light, or is not used, depending on the intended use and the configuration of the light source device. It can be divided into light of various wavelength bands.

Therefore, with the above configuration, the light that is first reflected by the first reflecting portion and travels toward the second reflecting portion is reflected by the first reflecting portion of the light emitted from the light emitting body. becomes part of the light For this reason, compared to the case where the first reflecting section is composed of a normal mirror, the heat generated by each reflecting section is reduced according to the amount of light not reflected by the first reflecting section.

Further, by adjusting the wavelength band of the light reflected by the first reflecting portion, the light source device can be configured to emit light in which the intensity of unnecessary wavelength bands is sufficiently reduced from the light extraction portion. .

A dichroic mirror, a bandpass filter, an IR cut filter, or the like can be used as the wavelength selection mirror, for example. Also, the light absorbing portion is formed by, for example, applying black body paint or black plating to the surface of the wavelength selection mirror opposite to the reflecting surface. Also, the wavelength selection mirror may be made of colored glass or the like, and the wavelength selection mirror itself may be configured to absorb light.

In the above light source device,
The luminous body may include the second reflecting portion.

For example, an LED, an LD, a fluorescent light source, or the like can be used as such a light emitter. A light source device using these light emitters does not need to additionally dispose a member that constitutes the second reflecting section, so that the entire device can be made small.

In the above light source device,
The second reflecting section includes a light guiding section that guides the light emitted from the light emitter to the specific region,
The light guiding section may guide the light passing through the specific region after being reflected by the first reflecting section to the light emitter.

With the above configuration, the light emitted from the light emitter is guided to the specific region regardless of the direction in which the light emitting surface of the light emitter faces. Then, the light that is reflected by the first reflecting portion and travels toward the specific region is guided toward the light emitting surface of the light emitter that constitutes the second reflecting portion.

In the above light source device,
When viewed from the minor axis direction, the light supply surface includes, within the specific region, a light emitting surface for emitting light emitted from the light emitter toward the first reflecting portion, and the light emitting surface. and the second reflecting portion extending outward.

With the above configuration, even if there is an area in which the light emitting surface of the light emitting body is not arranged in the specific area when viewed from the minor axis direction, the second reflecting section Light that has traveled to the region can be re-reflected toward the first reflecting portion.

In the above light source device,
When viewed from the minor axis direction, the light supply surface includes, within the specific region, a light emitting surface for emitting light emitted from the light emitter toward the first reflecting portion, and the light emitting surface. and the second reflecting portion extending outward.

With the above configuration, the light emitted from the light emitter toward the specific area is emitted from the specific area as it is. In addition, light that does not go directly to the specific area but is guided to the specific area by the light guide member can reach the specific area with the minimum necessary number of reflections, so the attenuation of the light intensity due to reflection can be minimized. can be reduced to

In the above light source device,
The light emitting body may include a plurality of light emitters arranged on a plane.

With the above configuration, the light source device collectively emits the light emitted from the plurality of light emitters from the light extraction portion, so that higher luminance can be achieved than in the light source device having a single light emitting portion.

In the above light source device,
The translucent member may have an outer surface along the shape of the rotating body, and the first reflecting portion may be formed on the outer surface.

With the above configuration, the light source device does not need to separately arrange a member for supporting the first reflecting section. Furthermore, since the translucent member can also serve as a lens that reduces the emission angle of the light emitted from the light extraction section, it is possible to realize a light source device with higher brightness.

In the above light source device,
The luminous body may be composed of a fluorescent member that emits fluorescence when excited light is applied from the outside.

With the above configuration, the configuration of the entire device can be freely configured by adjusting the shape of the fluorescent member, and light of a desired wavelength can be obtained by selecting the material of the fluorescent member.

In the above light source device,
The luminous body is composed of an optical member in which a phosphor is dissolved or diffused inside a bulk member, and an excitation light source is provided on the outer surface of the optical member,
The second reflecting portion may be formed on at least one of the outer surface of the optical member and the excitation light source.

In the above light source device,
The light emitter is composed of an optical member in which a phosphor is dissolved or diffused inside a bulk member, and an excitation light source and the second reflector are provided on the outer surface of the optical member,
The second reflection unit comprises an optical element having transparency to the excitation light from the excitation light source,
The excitation light may be incident on the light emitter via the second reflection section.

With the above configuration, the light emitter also includes the second reflecting portion, so that the entire light source device can be made small.

ADVANTAGE OF THE INVENTION According to this invention, the light source device which can raise the utilization efficiency of the light emitted from a light-emitting body, and can raise the brightness|luminance in a light emission region is implement|achieved.

It is a sectional view showing typically the composition of a first embodiment of a light source device. It is a top view when the light source device of FIG. 1A is seen from a Z direction. FIG. 1B is a plan view of the light source device from which the first reflecting portion of FIG. 1A is removed, as viewed in the Z direction; FIG. 10 is a perspective view schematically showing an operation of forming a body of revolution shape when rotating a semi-ellipse with a minor axis as a rotation axis. FIG. 3 is a plan view when the rotation operation of FIG. 2 is viewed from the Z direction; FIG. 3 is a schematic cross-sectional view of the mirror of FIG. 2 cut along a plane including a short axis; It is a sectional view showing typically an example of another composition of a first embodiment of a light source device. It is a sectional view showing typically an example of another composition of a first embodiment of a light source device. It is a sectional view showing typically composition of a second embodiment of a light source device. It is a sectional view showing typically composition of a third embodiment of a light source device. FIG. 8B is a plan view of the light source device of FIG. 8A with the first reflector removed and viewed from the Z direction; It is a sectional view showing typically composition of a fourth embodiment of a light source device. It is a sectional view showing typically another composition of a fourth embodiment of a light source device. It is a sectional view showing typically composition of a fifth embodiment of a light source device. It is a sectional view showing typically composition of a sixth embodiment of a light source device. It is a sectional view showing typically composition of a seventh embodiment of a light source device. It is a sectional view showing typically the composition of another embodiment of a light source device. It is a sectional view showing typically the composition of another embodiment of a light source device. It is a sectional view showing typically the composition of another embodiment of a light source device. It is a sectional view showing typically the composition of another embodiment of a light source device. It is a schematic cross-sectional view when the configuration of another embodiment of the light source device is viewed from the Z direction. FIG. 4 is a schematic cross-sectional view of a hemispherical mirror cut along a plane including the center;

Hereinafter, the light source device of the present invention will be described with reference to the drawings. It should be noted that the following drawings are all schematic illustrations, and the dimensional ratios and numbers in the drawings do not necessarily match the actual dimensional ratios and numbers.

[First embodiment]
FIG. 1A is a cross-sectional view schematically showing the configuration of the first embodiment of the light source device 1. FIG. FIG. 1B is a plan view of the light source device 1 of FIG. 1A as seen from the Z direction. FIG. 1C is a plan view of the light source device 1 from which the first reflecting portion 11 of FIG. 1A, which will be described later, is removed, as viewed in the Z direction. As shown in FIGS. 1A to 1C, the first embodiment of the light source device 1 includes a light emitting body 10 and at least a part of a rotating body whose rotation axis is a short axis of a semi-ellipse whose major axis is a chord. and a light extraction part 12 for extracting light to the outside of the light source device 1 .

Here, a body of revolution obtained by rotating an ellipse around its minor axis is called an oblate sphere. Therefore, the reflecting surface 11A of the first reflecting portion 11 has a shape that conforms to the outer shape of this oblate sphere. In the following description, the direction of the short axis of the semi-ellipse and the body of revolution is the Z direction, and the plane orthogonal to the Z direction is the XY plane. At this time, FIG. 1A corresponds to a cross-sectional view when the first embodiment of the light source device 1 is cut along the YZ plane at a predetermined X coordinate position.

In this specification, to distinguish between positive and negative directions when expressing directions, positive and negative signs are added, such as “+Z direction” and “−Z direction”. Moreover, when a direction is expressed without distinguishing between positive and negative directions, it is simply described as “Z direction”.

FIG. 2 is a perspective view schematically showing the operation of forming a body of revolution when rotating a semi-ellipse with the minor axis Sx as the rotation axis. FIG. 3 is a plan view of the rotational movement of FIG. 2 as seen from the Z direction. As shown in FIGS. 2 and 3, when the semi-ellipse is rotated around the minor axis Sx, a body of revolution is formed and the focal point F of the semi-ellipse draws a circle around the minor axis Sx. Draw a trajectory line. In this specification, an area surrounded by a closed curve defined by the trajectory of this focal point F is called a specific area Fa. In FIG. 2, the specific area Fa is indicated by hatching.

As shown in FIGS. 1A to 1C, the light emitting body 10 has a light supply surface 10A for emitting light from within the specific area Fa toward the first reflecting portion 11 side. More specifically, in the first embodiment, the light emitting body 10 includes the light emitting body 10L and the second reflecting section 10C, and includes the light guide section 13 forming a part of the second reflecting section 10C. With this configuration, the light emitting body 10 emits light from the specific area Fa toward the first reflecting portion 11 by light emission or light reflection.

As shown in FIG. 1A, the light emitting body 10 has a second reflection that re-reflects the light reflected by the first reflecting portion 11 and incident on the specific region Fa from the specific region Fa toward the first reflecting portion 11. A part 10C is provided. In addition, the second reflecting section 10</b>C of the light source device 1 of the first embodiment is configured by combining with the light guiding section 13 .

The light guiding portion 13, which constitutes a part of the second reflecting portion 10C, guides the light that has been reflected by the first reflecting portion 11 and has entered the specific region Fa, and again passes through the specific region Fa to the first reflecting portion Part of the role of re-reflection towards 11. Here, the light reflected by the first reflecting portion 11 and passing through the specific area Fa is guided to the light emitting surface of the light emitter 10L, and the light reflected again by the light emitting surface is directed toward the specific area Fa again. It has the function of guiding light. It also has a function of guiding the light emitted from the light emitting surface of the light emitter 10L to the specific area Fa. This light guide section 13 can be configured by, for example, a cylindrical mirror, a rod lens, or the like.

Therefore, the light emitted from the light emitter 10L is repeatedly reflected between the first reflecting portion 11 and the second reflecting portion 10C via the specific area Fa, and eventually reaches the outside of the light source device 1 from the light extraction portion 12. radiated toward

In the Z direction, the light supply surface 10A is arranged on the same plane as the specific area Fa. Here, "arranged on the same plane" means that a deviation of the order of a manufacturing error has a slight effect and is permissible. Further, if the light emitting body 10 is arranged to emit light in the direction toward the first reflecting portion 11 from the specific region Fa, the light supply surface 10A and the specific region Fa are not necessarily arranged on the same plane. I don't mind. In this case, in the Z direction, the light supply surface 10A may be slightly separated from the specific area Fa, and if the separation distance is within ±10% with respect to the minor axis radius of the first reflecting portion, the present invention You can enjoy the effect of, and you can allow it.

The luminous body 10L may have a minute uneven surface on its luminous surface, or a reflective surface that reflects the light propagated inside the luminous body 10L may be formed inside the luminous body 10L or on the back side of the luminous body 10L. Also in the case where the can be admitted. Moreover, of course, the second reflecting portion 10C may be provided separately from the light emitter 10L.

The first reflecting portion 11 is formed in a concave shape along the shape of a rotating body whose rotation axis is the minor axis of a semi-ellipse whose chord is the major axis Lx. Note that the first reflecting portion 11 only needs to have a function of reflecting light emitted from the light emitting body 10, and its member is not particularly limited. be done.

In the light source device 1 of the first embodiment, the light extraction portion 12 is formed in a partial area of the first reflection portion 11 . More specifically, when the light source device 1 of the first embodiment is viewed from the Z direction, a circular light extraction portion 12 is formed near the center of the first reflection portion 11 .

The light extraction part 12 may be composed of a simple opening, or may be covered with a member having transparency to the light emitted from the light emitting body 10 . In the latter case, for example, it can be made of resin, glass, or the like.

Next, referring to FIGS. 2 to 4, the features of the shape of the rotating body whose rotation axis is the minor axis Sx of the semi-ellipse with the long axis Lx as its chord, a mirror formed along the concave shape of the rotating body. 20. FIG. 4 is a schematic cross-sectional view of the mirror 20 of FIG. 2 cut along a plane including the minor axis Sx. As shown in FIGS. 2 to 4, a cross section 20A obtained by cutting the mirror 20 along an arbitrary plane parallel to the minor axis Sx has a semi-elliptical shape having a minor axis Sx and a major axis Lx. There are two focal points (F1, F2).

First, consider light traveling on cross-section 20A of mirror 20 . As indicated by the dashed line in FIG. 4, the light from the focal point F1 is reflected by the mirror 20 in a direction folded back by the normal line of the reflecting surface at the point N1, and travels toward the other focal point F2. Also, the light from the focal point F2 is reflected by the mirror 20 and travels toward the focal point F1 again.

4, the light emitted from the area between the focal points (F1, F2) is reflected by the mirror 20 in a direction folded back by the normal line of the reflecting surface at the point N1, Again proceed towards the area between foci (F1, F2). That is, in the section 20A, the light emitted along the section 20A from the area between the focal points (F1, F2) is reflected again by the mirror 20 to the area between the focal points (F1, F2).

As shown in FIGS. 2 and 3, the reflective surface formed in the shape of a body of revolution formed by rotating a semi-ellipse with the major axis Lx as its chord and the minor axis Sx as the axis of rotation can be formed in any position passing through the minor axis Sx. It has the same effect on the cross section 20A. That is, in any cross section 20A passing through the short axis Sx, as described above, the light emitted from the area between the focal points (F1, F2) is re-directed by the mirror 20 to the area between the focal points (F1, F2). It will be reflected in the area.

In addition, the inventors conducted further intensive studies and discovered an optical effect that light emitted from an arbitrary light-emitting point within a specific area always returns to the specific area, even for light rays that do not pass through the cross section 20A. . That is, the reflective surface formed in the shape of a body of revolution formed by rotating a semi-ellipse with the major axis Lx as the chord and the minor axis Sx as the axis of rotation is a closed curve defined by the trajectory of the focus (F1, F2) of the ellipse. In the specific area Fa surrounded by , in principle, all light rays emitted from this specific area Fa are reflected by the reflecting surface and returned to the specific area again, and this is also confirmed by optical simulation confirmed.

Therefore, the mirror 20 formed in the shape of a body of revolution formed by rotating a semi-ellipse with the major axis Lx as its chord about the minor axis Sx is the focal point when the cross section 20A is rotated about the minor axis Sx. When passing through the specific area Fa surrounded by the closed curve defined by the trajectory of (F1, F2), such light is reflected by the mirror 20 after passing through the specific area Fa, and is reflected again by the specific area Fa. Proceed into Fa.

That is, the light traveling from the specific area Fa toward the first reflecting section 11 is reflected by the first reflecting section 11 and travels toward the specific area Fa, as shown in FIG. 1A. Then, the light reflected from the first reflecting portion 11 toward the specific region Fa travels again from the specific region Fa toward the first reflecting portion 11 side by the second reflecting portion 10C provided in the light emitting body 10 . As a result, reflection is repeated between the first reflecting portion 11 and the specific area Fa.

In the light source device 1 shown in FIGS. 1A to 1C, the light emitting body 10 arranged in the specific area Fa emits light from the light supply surface 10A toward the first reflecting portion 11 or the light extracting portion 12. Of the light emitted from the light emitting body 10 , the light traveling toward the light extraction portion 12 is emitted outside the light source device 1 as it is.

Of the light emitted from the light supply surface 10A of the light emitting body 10, the light traveling toward the first reflecting portion 11 is reflected by the first reflecting portion 11 toward the specific area Fa. The light returned to the specific region Fa travels again from the specific region Fa toward the first reflecting portion 11 side by the second reflecting portion 10C formed on the light emitting body 10, and then travels toward the first reflecting portion 11 and Reflection is repeated between the second reflecting portion 10C.

The light repeatedly reflected between the first reflecting portion 11 and the second reflecting portion 10</b>C eventually travels toward the light extraction portion 12 and is emitted toward the outside of the light source device 1 . That is, although the intensity of the light emitted from the light supply surface 10A of the light emitting body 10 is slightly attenuated by reflection, in principle all the light emitted from the light supply surface 10A is returned to the light supply surface 10A. and can be reused from the light supply surface 10A as reflected light. Therefore, the brightness in the area of the light supply surface 10A can be improved compared to the conventional configuration.

Note that the shape of the second reflecting portion 10C is not limited to the configuration shown in FIGS. 1A to 1C. For example, FIG. 5 is a cross-sectional view schematically showing an example of another configuration of the first embodiment of the light source device 1. As shown in FIG. As shown in FIG. 5, a light emitting surface is configured on a plane different from the XY plane, and light emitted from the light emitting surface is guided to the specific area Fa by the light guide portion 13 provided in the second reflecting portion 10C. can be configured. More specifically, the light emitted from the light emitting surface and traveling in the Y direction travels toward the first reflecting portion 11 after the traveling direction is changed to the Z direction while being guided through the light guide portion 13 . . After the light reflected by the first reflecting portion 11 enters the specific region Fa, the traveling direction of the light is changed to the Y direction while being guided through the light guiding portion 13, and the light emitting body 10L (the second reflecting portion 10C ).

FIG. 6 is a cross-sectional view schematically showing an example of another configuration of the first embodiment of the light source device 1. As shown in FIG. As shown in FIG. 6, the light source device 1 includes the light supply surface of the light emitting body 10 so as to face the specific area Fa when viewed in the Z direction from the first reflecting portion 11 side toward the light emitting body 10 side. 10A may be arranged and the light emitting body 10 may be configured to be larger than the specific area Fa. In addition, it is more preferable that the range of the light emitting surface 10B provided in the light supply surface is entirely accommodated in the specific area Fa. Further, it is desirable that the second reflecting portion 10C is formed so as to extend over the entire area within the specific area Fa when viewed from the Z direction.

[Second embodiment]
The configuration of the second embodiment of the light source device 1 of the present invention will be described, focusing on the points different from the first embodiment.

FIG. 7 is a cross-sectional view schematically showing the configuration of the second embodiment of the light source device 1. As shown in FIG. As shown in FIG. 7, in the second embodiment of the light source device 1, the light supply surface 10A is composed of the light emitting surface 10B and the second reflecting portion 10C (10C3). The light reflected by the reflecting portion 11 and traveling toward the light emitting body 10 side is re-reflected toward the first reflecting portion 11 side. In addition, in the second embodiment, the light guide section 13 of the second reflection section 10C is composed of a cylindrical mirror, but they may be composed of different members separately.

The light guide section 13 has a function of guiding the light emitted from the light emitting surface of the light emitter 10L to the specific area Fa. In addition, the second reflecting portion 10C is positioned within the specific area Fa when viewed from the Z direction.

As described above, in the first embodiment of the light source device 1, the light traveling toward the specific area Fa after being reflected by the first reflecting portion 11 is reflected again by the second reflecting portion 10C provided in the light emitter 10L. It is reflected toward the specific area Fa. On the other hand, in the second embodiment of the light source device 1, part of the light reflected by the first reflector 11 and traveling toward the specific area Fa is reflected by the second reflector 10C3 forming the light supply surface 10A. The light is reflected so as to travel from the specific area Fa toward the first reflecting portion 11 side.

[Third embodiment]
The configuration of the third embodiment of the light source device 1 of the present invention will be described, focusing on the points different from those of the first and second embodiments.

FIG. 8A is a cross-sectional view schematically showing the configuration of the third embodiment of the light source device 1. FIG. 8B is a plan view of the light source device 1 of FIG. 8A with the first reflecting section 11 removed and viewed in the Z direction. As shown in FIGS. 8A and 8B, in the third embodiment of the light source device 1, the light emitting body 10 is a light emitting body 10L having a light supply surface 10A.

In addition, when viewed from the Z direction, in the specific region Fa, the second reflecting portion 10C extends even in a region 10S that does not overlap with the light emitting surface 10P, which is the light emitting surface of the light emitter 10L, to extend the light supply surface 10A. In this way, it is possible to effectively utilize even the light not directed toward the light emitting surface 10P among the lights reflected from the first reflecting portion 11 into the specific area Fa. Further, it is more desirable that the second reflecting portion 10C be formed so as to extend over the entire area within the specific area Fa when viewed from the Z direction.

[Fourth embodiment]
The configuration of the fourth embodiment of the light source device 1 of the present invention will be described, focusing on the points different from those of the first, second, and third embodiments.

FIG. 9A is a cross-sectional view schematically showing the configuration of the fourth embodiment of the light source device 1. FIG. FIG. 9B is a cross-sectional view schematically showing another configuration of the fourth embodiment of the light source device 1. FIG. As shown in FIGS. 9A and 9B , in the light source device 1 of the fourth embodiment, a translucent member 50 is filled between the first reflecting section 11 and the light emitting body 10 . Further, in FIG. 9A, the light supply surface 10A and the specific area Fa are arranged so as to match in the Z direction. Although the light emitting body 10 shown in FIG. 9A is composed of the light emitting body 10L and the second reflecting portion 10C, it is not limited to this, and the light emitting body 10 described in other embodiments is applied. I don't mind if you let me.

The light-transmitting member 50 has the shape of a rotating body formed by rotating a semi-ellipse with the major axis Lx as a chord and the minor axis Sx as the rotation axis, that is, has an outer surface along the first reflecting portion 11 . and the light reflected by the first reflecting section 11. For example, it is made of a material such as epoxy, transparent silicone, acrylic, optical glass, quartz glass or other resin, or glass. be.

Further, as shown in FIGS. 9A and 9B , the light-transmitting member 50 may have a curved surface at the light extraction portion 12 . Since the translucent member 50 forms a curved surface in the light extraction portion 12, the divergence angle of the light emitted from the light extraction portion 12 can be narrowed and used.

The light source device 1 of FIG. 9A exemplifies a configuration in which the translucent member 50 is filled between the first reflecting portion 11 and the light supply surface 10A of the light emitting body 10 . Further, the light source device 1 of FIG. 9B exemplifies a configuration in which the translucent member 50 is filled between the first reflecting portion 11 and the light emitting body 10 sealed with the sealing member 51 .

The configurations shown in FIGS. 9A and 9B are configured so that the light supply surface 10A of the light emitting body 10 and the specific area Fa are arranged on the same plane. Fa may not be on the same plane. 9B, the sealing member 51 is transparent to the light emitted from the light emitting body 10 and the light reflected by the first reflecting portion 11, similarly to the translucent member 50. , such as epoxy, transparent silicone, acrylic, optical glass, resin such as quartz glass, or glass.

[Fifth embodiment]
The configuration of the fifth embodiment of the light source device 1 of the present invention will be described, focusing on the points different from those of the first to fourth embodiments.

FIG. 10 is a cross-sectional view schematically showing the configuration of the fifth embodiment of the light source device 1. As shown in FIG. As shown in FIG. 10, the light emitting body 100 of the fifth embodiment includes a fluorescent plate 100L corresponding to a light emitter and an excitation light source 100E that emits light for exciting the phosphor contained in the fluorescent plate 100L.

When excitation light is incident on the fluorescent plate 100L from an excitation light source 100E arranged on the opposite side of the first reflecting portion 11, the phosphor contained in the fluorescent plate 100L is excited, and light is emitted from the light supply surface 100A. In the fifth embodiment, the fluorescent screen 100L is positioned within the specific area Fa when viewed from the Z direction.

The light supply surface 100A of the fluorescent plate 100L also functions as a second reflecting portion 100C that re-reflects the light that is reflected by the first reflecting portion 11 and travels toward the specific area Fa toward the first reflecting portion 11 side. concurrently. In addition, although not shown, a second reflecting portion 100C may be separately provided on the back side of the fluorescent plate 100L, which is expected to have the effect of increasing the amount of light re-reflected toward the first reflecting portion 11. can. As shown in FIG. 10, in the fifth embodiment, the light supply surface 100A of the fluorescent plate 100L is arranged on the same plane as the specific area Fa, but the light supply surface 100A and the specific area Fa are not necessarily the same. It does not matter if it is not on a plane.

For example, an LED, an LD, or the like can be used as the excitation light source 100E. Further, as shown in FIG. 10, the light source device 1 of the fifth embodiment is configured such that the light emitted from the excitation light source 100E is directly incident on the fluorescent plate 100L. The light emitted from the light source 100E may be guided by a light guide member or the like and incident on the fluorescent plate 100L.

Alternatively, the light supply surface 100A of the fluorescent plate 100L may be composed of, for example, a light emitting surface for emitting light from the fluorescent plate 100L and a second reflecting portion 100C provided therearound, as shown in FIG. good. Specifically, when viewed from the Z direction, the second reflecting portion 100C may be formed in a region 100S where the light emitting surface of the fluorescent plate 100L does not overlap within the specific region Fa. Of the light reflected on the surface, the light not directed toward the light emitting surface can also be reflected again, and the light can be used effectively. Furthermore, it is more desirable that the second reflecting portion 100C be formed so as to extend over the entire area within the specific area Fa when viewed from the Z direction.

[Sixth embodiment]
The configuration of the sixth embodiment of the light source device 1 of the present invention will be described, focusing on the points different from those of the first to fifth embodiments.

FIG. 11 is a cross-sectional view schematically showing the configuration of the sixth embodiment of the light source device 1. As shown in FIG. As shown in FIG. 11, the luminous body 110 of the sixth embodiment includes a fluorescent member 111 in which a fluorescent substance 110F is dissolved or diffused inside a bulk member (mass with a large volume, block-shaped member). , and an excitation light source 110 E on the outer surface of the fluorescent member 111 . Fluorescent member 111 contains phosphor 110F that is excited to emit fluorescence when light emitted from excitation light source 110E is incident thereon. Furthermore, on the light supply surface 110A arranged on the first reflecting portion 11 side of the fluorescent member 111, a second reflecting portion that re-reflects the light traveling toward the specific area Fa toward the first reflecting portion 11 side is provided. 110C is configured.

It should be noted that the second reflecting portion 110C does not necessarily need to be formed on the light supply surface 110A, and may be formed on another part of the light emitter 110. FIG. For example, a configuration in which the second reflecting portion 110C is formed on the outer surface of the fluorescent member 111 or the excitation light source 110E is conceivable.

The excitation light source 110E is a light source that emits light toward the fluorescent member 111, and may be an LED, an LD, or the like, for example.

As described above, the fluorescent member 111 guides the fluorescence emitted from the phosphor 110F to the light supply surface 110A arranged in the specific area Fa, and the light is emitted from the light supply surface 110A. Of the light emitted from the light supply surface 110A of the light emitter 110, the light traveling toward the first reflecting portion 11 is reflected by the first reflecting portion 11 into the specific area Fa. The light returned to the specific region Fa travels again from the specific region Fa toward the first reflecting portion 11 side by the second reflecting portion 110C formed on the light emitter 110, and then travels toward the first reflecting portion 11 and the first reflecting portion 11. Reflection is repeated between the two reflecting portions 110C.

Here, the fluorescent member 111 is a member that guides the fluorescence emitted from the fluorescent substance 110F to the light supply surface 110A and contains the fluorescent substance 110F. A so-called fluorescent rod lens or the like is sealed.

FIG. 11 shows a rectangular parallelepiped fluorescent member 111 having a square side cross-section, but the fluorescent member 111 may have a polygonal or cylindrical shape as long as it has a light supply surface 110A and a second reflecting portion 110C. , a hemispherical shape, or any other shape.

Also, the light supply surface 110A of the light emitter 110 may be composed of a light emitting surface and a second reflecting portion 110C extending around it, as shown in FIG. 8B, for example. More specifically, the second reflecting portion 110C may be formed in a region 110S that does not overlap the light emitting surface within the specific region Fa when viewed from the Z direction, so that the first reflecting portion 11 reflects light into the specific region Fa. Of the light directed toward the light emitting surface, the light that is not directed toward the light emitting surface can also be effectively utilized. Furthermore, it is desirable that the second reflecting portion 110C be formed so as to extend over the entire area within the specific area Fa when viewed from the Z direction.

Furthermore, a second reflector is provided on the outer surface of the light emitter 110, and the second reflector may be provided with an optical element having transparency to the excitation light from the excitation light source 110E. Optical elements are, for example, dichroic filters, dichroic prisms, and the like.

[Seventh embodiment]
The configuration of the seventh embodiment of the light source device 1 of the present invention will be described, focusing on the points different from those of the first to sixth embodiments.

FIG. 12 is a cross-sectional view schematically showing the configuration of the seventh embodiment of the light source device 1. As shown in FIG. As shown in FIG. 12, the first reflecting portion 11 of the seventh embodiment is formed by applying a black body paint that absorbs light transmitted through the first reflecting portion 11 on the side opposite to the reflecting surface 11A. A section 14 is provided.

Further, the first reflecting portion 11 of the seventh embodiment is formed along the shape of a rotating body formed by rotating a semi-ellipse with the major axis Lx as the chord and the minor axis Sx as the rotation axis. It is a dichroic mirror corresponding to a wavelength selection mirror in which a dielectric multilayer film is formed on the second side.

With the above configuration, the light emitted from the light emitting body 10 and traveling toward the first reflecting portion 11 has a part of the light in the wavelength band reflected by the first reflecting portion 11, and the light that is not reflected is the first It is absorbed by the reflecting portion 11 or transmitted through the first reflecting portion 11 and absorbed by the light absorbing portion 14 . Therefore, the amount of light traveling toward the second reflecting portion 10C is reduced, the amount of heat generated in the light emitter 10L is reduced, and a decrease in the luminous efficiency and conversion efficiency of the light emitter 10L is suppressed.

In addition, in FIG. 12 , the light absorbing portion 14 is formed over the entire outer surface of the first reflecting portion 11 , but may be formed only on a part of the first reflecting portion 11 . Further, in the case where the light transmitted through the first reflecting section 11 does not affect the subsequent optical system, the light absorbing section 14 may not be provided.

[Another embodiment]
Another embodiment will be described below.

<1> FIG. 13 is a cross-sectional view schematically showing the configuration of another embodiment of the light source device 1. As shown in FIG. As shown in FIG. 13, the light source device 1 may be composed of a light emitting body 10 having a plurality of light emitters 10L.

In addition, in FIG. 13, although the light source device 1 of the fourth embodiment includes a plurality of light emitters 10L, the same applies to each light source device 1 of other embodiments.

<2> FIG. 14 is a cross-sectional view schematically showing the configuration of another embodiment of the light source device 1. As shown in FIG. As shown in FIG. 14, the light guide portion 13 narrows the light distribution range of the light emitted from the light emitting body 10, and the first reflecting portion 11 is provided only at the portion where the light emitted from the light emitting body 10 reaches. It does not matter if they are formed. By configuring in this way, the size of the first reflecting portion 11 is not unnecessarily large, so that the light source device 1 as a whole can be miniaturized. Note that the light source device 1 of the present embodiment is not limited to the configuration of FIG. 14, and may adopt a configuration that narrows the light distribution range of the light emitted from the light emitting body 10 using other optical members.

<3> FIG. 15 is a cross-sectional view schematically showing the configuration of another embodiment of the light source device 1. As shown in FIG. In each embodiment of the light source device 1 described above, the light extraction section 12 is configured to emit light in the Z direction. It may be formed so as to For example, as shown in FIG. 15, the light extraction part 12 may be formed so as to emit light in a direction perpendicular to the Z direction.

<4> FIG. 16 is a cross-sectional view schematically showing the configuration of another embodiment of the light source device 1. As shown in FIG. As shown in FIG. 16, the light supply surface 10A of the light emitting body 10 constitutes part of the second reflecting part 10C so as to coincide with the specific area Fa or between the specific area Fa and the light emitter 10L. A diffusion member 150 for diffusing light may be provided as a member for diffusing light.

According to this configuration, the diffusion member 150 scatters the light that is difficult to be emitted from the light extraction portion 12 even if the reflection is repeated between the first reflection portion 11 and the specific region Fa. It can be made to advance toward and the intensity|strength of the light emitted from the light source device 1 can be improved. In addition, the diffusion member 150 is not limited to a configuration in which it is arranged as a separate body, and may have a function of diffusing the light incident on the light supply surface 10A of the light emitting body 10 or the second reflection portion 10C itself. .

<5> FIG. 17 is a schematic cross-sectional top view of the configuration of another embodiment of the light source device 1 when viewed from the Z direction. As shown in FIG. 17, the light source device 1 includes a light absorbing member 160 that absorbs light outside the specific area Fa when viewed in the Z direction from the first reflecting portion 11 side to the light emitting body 10 side. It doesn't matter if

When light propagates to a region outside the specific region Fa due to disturbance light from the outside, an abnormal shape of the first reflecting portion 11, or the like, it may be emitted from the light extraction portion 12 as stray light. In order to suppress such stray light, it is preferable to attach the light absorbing member 160 as shown in the above configuration. Thereby, the light distribution range of the light emitted from the light source device 1 can be appropriately controlled.

<6> The configuration provided in the light source device 1 described above is merely an example, and the present invention is not limited to each illustrated configuration.

Reference Signs List 1: Light source device 10: Light emitting body 10A: Light supply surface 10B: Light emitting surface 10C: Second reflecting part 10L: Light emitter 10P: Light emitting surface 10S: Area 11: First reflecting part 11A: Reflecting surface 12: Light Extracting part 13: Light guide part 14: Light absorbing part 20: Mirror 20A: Cross section 50: Translucent member 51: Sealing member 100: Light emitting body 100A: Light supply surface 100C: Second reflecting part 100E: Excitation light source 100L: Fluorescent plate 100S: Region 110: Light emitter 110A: Light supply surface 110C: Second reflector 110E: Excitation light source 110F: Phosphor 110S: Region 111: Fluorescent member 150: Diffusion member 160: Light absorbing member 200: Mirror 201: Light emitting region F1, F2: Focal point Fa: Specific area Lx: Long axis Sx: Short axis

Claims (12)

a first reflecting portion having a concave reflecting surface along at least a portion of a body of revolution formed by rotating a semi-ellipse with the major axis of the ellipse as the chord, with the minor axis of the ellipse as the axis of rotation;
a light extraction portion that emits light to the outside of the first reflection portion;
An area surrounded by a closed curve defined by the trajectory of the focal point of the ellipse when rotated about the short axis is defined as a specific area, and light is emitted from the specific area toward the first reflecting section. or a light emitting body constituting a light supply surface that emits light by light reflection,
The light emitting body is
a light emitter that produces light emitted from the light-providing surface;
A light source device, further comprising: a second reflecting section that re-reflects light reflected by the first reflecting section toward the specific area from the specific area toward the first reflecting section. 2. The light source device according to claim 1, wherein the light supply surface of the light emitting body is arranged so as to substantially coincide with the specific region in the minor axis direction. The first reflecting portion is a wavelength selection mirror that reflects light in a partial wavelength band of the light emitted from the specific region and traveling toward the first reflecting portion toward the specific region. 3. The light source device according to claim 1, wherein: 4. The light source device according to claim 3, further comprising a light absorbing portion that absorbs the light transmitted through the first reflecting portion on the side opposite to the reflecting surface of the first reflecting portion. The light source device according to any one of claims 1 to 4, wherein the light emitter includes the second reflecting section. The second reflecting section includes a light guiding section that guides the light emitted from the light emitter to the specific region,
6. The light source device according to claim 5, wherein the light guide section guides the light passing through the specific region after being reflected by the first reflecting section to the light emitter. When viewed from the minor axis direction, the light supply surface includes, within the specific region, a light emitting surface for emitting light emitted from the light emitter toward the first reflecting portion, and the light emitting surface. 7. The light source device according to any one of claims 1 to 6, wherein the second reflecting portion extends outward. 8. The light source device according to any one of claims 1 to 7, wherein said light emitting body comprises a plurality of said light emitters arranged on a plane. 9. The translucent member according to any one of claims 1 to 8, wherein the translucent member has an outer surface along the shape of the rotating body, and the first reflecting portion is formed on the outer surface. Light source device. 10. The light source device according to any one of claims 1 to 9, wherein the luminous body is composed of a fluorescent member that emits fluorescence when excited light is applied from the outside. The luminous body is composed of an optical member in which a phosphor is dissolved or diffused inside a bulk member, and an excitation light source is provided on the outer surface of the optical member,
11. The light source device according to claim 10, wherein the second reflecting portion is formed on at least one of the outer surface of the optical member and the excitation light source. The light emitter is composed of an optical member in which a phosphor is dissolved or diffused inside a bulk member, and an excitation light source and the second reflector are provided on the outer surface of the optical member,
The second reflection unit comprises an optical element having transparency to the excitation light from the excitation light source,
11. The light source device according to claim 10, wherein excitation light is incident on said light emitter via said second reflecting portion.

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