JP2022108288A - Wavelength conversion wheel, light source device, and projection device - Google Patents

Abstract

To provide a wavelength conversion wheel that is less likely to be defective.SOLUTION: A wavelength conversion wheel 20 has a plurality of wheel members 221, a fixture 25 that fixes the plurality of wheel members 221 in a disc shape, and a wavelength conversion layer arranged on the plurality of wheel members 221.SELECTED DRAWING: Figure 2

Description

The present disclosure relates to wavelength conversion wheels, light source devices, and projection devices.

For example, Patent Literature 1 discloses a phosphor wheel (wavelength conversion wheel) in which a phosphor layer (wavelength conversion layer) that is excited by laser light and emits fluorescence is formed on a disk-shaped substrate.

JP 2015-166804 A

For example, when the wavelength conversion layer is damaged, the wavelength conversion wheel described in Cited Document 1 cannot emit light with a predetermined intensity, which can make it difficult to use. Further, for example, when manufacturing a wavelength conversion wheel, the wavelength conversion layer is divided into a plurality of segments that emit predetermined colors. Therefore, when the wavelength conversion layer is formed, there is a possibility that it may become a defective product if there is a non-uniform portion. A main object of the present disclosure is, for example, to provide a wavelength conversion wheel that is less likely to be defective.

A wavelength conversion wheel according to one aspect of the present disclosure includes a plurality of wheel members, a fixture that fixes the plurality of wheel members in a disc shape, and a wavelength conversion layer arranged on the plurality of wheel members.

It is a schematic diagram showing an example of a light source device typically. FIG. 2 is a plan view schematically showing an example of a wavelength conversion wheel rotating device; FIG. 3 is a side view of the wavelength conversion wheel rotating device of FIG. 2; FIG. 2 is a plan view schematically showing an example of a wheel substrate; 2 is a plan view schematically showing a wavelength conversion wheel of Configuration Example 1. FIG. FIG. 11 is a plan view schematically showing a wavelength conversion wheel of Configuration Example 2; FIG. 11 is a plan view schematically showing a wavelength conversion wheel of Configuration Example 3; It is a schematic diagram showing an example of a projection device typically.

The embodiments described below are merely exemplary of the present disclosure. The present disclosure is by no means limited to the following embodiments. In addition, in the following embodiments, the same constituent elements may be denoted by the same reference numerals, and detailed description thereof may be omitted.

<Embodiment 1>
<Light source device>
FIG. 1 shows a schematic diagram of an example of a light source device. FIG. 2 is a schematic plan view (xy plane) of the wavelength conversion wheel rotating device. FIG. 3 is a schematic side view (xz plane) of the wavelength conversion wheel rotating device.

The light source device 100 includes an optical system 10 , a wavelength conversion wheel rotating device 20 and a light source 30 . The light source device 100 is a device that irradiates the wavelength conversion layer 24 of the wavelength conversion wheel 21 with light emitted from the light source 30 and extracts the light emitted from the wavelength conversion layer 24 .

The light source 30 irradiates the wavelength conversion layer 24 with excitation light 31, for example. The excitation light 31 is, for example, light with a wavelength that excites the wavelength conversion material contained in the wavelength conversion layer 24 . Various ranges can be used for the wavelength band of the excitation light 31 according to the design of the light source device 100, for example. As the light source 30, for example, a blue light source can be used, preferably a blue laser diode.

The optical system 10 includes, for example, a biconvex lens 13, a dichroic mirror 11, and single convex lenses 14 and 15, as shown in FIG. The optical system 10 is composed of an input optical system for inputting the excitation light 31 emitted by the light source 30 into the wavelength conversion wheel rotating device 20 and an output optical system for outputting the light from the wavelength conversion wheel rotating device 20. .

The incident optical system, for example, causes the excitation light 31 from the light source 30 to enter the wavelength conversion layer 24 of the wavelength conversion wheel 21 via the biconvex lens 13 , the dichroic mirror 11 , and the single convex lenses 215 and 214 . The emission optical system emits the light 105 from the wavelength conversion layer 24 by the incident excitation light 31 via the single-convex lenses 14 and 15 and the dichroic mirror 11, for example. The dichroic mirror 11, for example, reflects blue light and transmits yellow and red light.

For example, when light of a specific wavelength (excitation light) is incident, the wavelength conversion layer 24 emits light of a wavelength different from the excitation light, typically light of a longer wavelength than the excitation light. Wavelength conversion layer 24 includes, for example, a wavelength conversion material. For example, when light of a specific wavelength (excitation light) is incident on the wavelength conversion material, the wavelength conversion material emits light of a wavelength different from the excitation light, typically light of a longer wavelength than the excitation light. The wavelength converting material is preferably an inorganic wavelength converting material, eg a phosphor.

Materials for the wavelength conversion material include, for example, YAG:Ce (Y ₃ Al ₅ O ₁₂ :Ce ³⁺ ), CaAlSiN ₃ :Eu ²⁺ , Ca-α-SiAlON: Eu ²⁺ , β-SiAlON: Eu ²⁺ , Lu ₃ Al _5O12 :Ce3 ⁺ ( _LuAG :Ce), ₍ Sr, Ca, Ba, Mg) _{10 (} PO4) _6C12 :Eu, _BaMgAl10O17 : _Eu2 ⁺ , ₍ Sr _, Ba) _3MgSi2O8 : Eu ²⁺ and the like. A material for the wavelength conversion material is appropriately selected according to the emission colors of the wavelength conversion layer 24 and the segments 241 .

The shape of the wavelength conversion material is not particularly limited, and may be, for example, particulate, spherical, ellipsoidal, acicular, polygonal prismatic, cylindrical, or the like. The average particle size of the wavelength conversion material is, for example, preferably several μm or more and several tens of μm or less, more preferably 1 μm or more and 50 μm or less, and even more preferably 5 μm or more and 30 μm or less. The wavelength conversion material may be of one type or a mixture of multiple types.

The thicknesses of the wavelength conversion layer 24 and the segments 241 are, for example, preferably 20 μm to 200 μm, more preferably 50 μm to 100 μm. If the thickness of the wavelength conversion layer 24 and the segments 241 is small, the excitation light absorption of the wavelength conversion material may be insufficient, resulting in low luminous efficiency. On the other hand, if the thickness of the wavelength conversion layer 24 is thin, the heat generated by absorption of the excitation light by the wavelength conversion material is less likely to escape to the wheel substrate 23, and the temperature of the wavelength conversion layer 24 may rise. The wavelength conversion material may decrease in emission intensity as the temperature increases.

The wavelength conversion wheel rotating device 20 includes, for example, a wavelength conversion wheel 21 , a rotating shaft 26 and a driving device 27 .

The wavelength conversion wheel 21 has, for example, a plurality of wheel members 221 and wheel fixtures 25 .

The wheel fixture 25 fixes, for example, a plurality of wheel members 221 in a disc shape. The wheel fixtures 25, for example, fix each wheel member 221 by sandwiching it in the thickness direction. The method of fixing each wheel member 221 to the wheel fixture 25 is not particularly limited, and may be fixed by screwing, for example.

Also, in other words, the wavelength conversion wheel 21 has a disc shape by being fixed by a wheel fixture 25, for example. In addition, for example, in the wavelength conversion wheel 21, the wheel members 221 adjacent to each other may be adhered with an adhesive. Thereby, in the wavelength conversion wheel 21, it is possible to suppress the displacement between adjacent wheel members 221. FIG.

Also, the wavelength conversion wheel 21 is fixed to a rotating shaft 26 . The method of fixing the wavelength conversion wheel 21 to the rotating shaft 26 is not particularly limited, and may be fixed using the wheel fixture 25, or may be fixed with an adhesive or the like.

The driving device 27 is, for example, a motor or the like controlled by electric signals, and is connected to the rotating shaft 26 .

The wavelength conversion wheel rotating device 20 rotates (rotates and stops) the wavelength conversion wheel 21 through a rotating shaft 26 connected to a driving device 27, for example. As a result, the position irradiated with the excitation light on the wavelength conversion layer 24 of the wavelength conversion wheel 21 is changed, preventing the wavelength conversion layer 24 from being excessively heated and increasing the temperature of the wavelength conversion material contained in the wavelength conversion layer 24. Quenching can be suppressed.

The wheel member 221 has, for example, a wheel substrate piece 231 and a segment 241 arranged on the wheel substrate piece 231 . Each segment 241 is part of the wavelength conversion layer 24 in the wavelength conversion wheel 21 , and is divided and arranged along the circumferential direction of the wavelength conversion wheel 21 . In other words, the wavelength conversion layer 24 has a plurality of segments 241 divided and arranged along the circumferential direction of the wavelength conversion wheel 21 . Further, each segment 241 may emit the same color, or may emit different colors.

FIG. 4 is a schematic plan view (xy plane) of an example of the wheel substrate 230 on which the wavelength conversion layer 240 is formed. The wheel substrate 230 is, for example, a disc-shaped substrate having a hole 28 in the center. The wavelength conversion layer 240 is formed along the circumferential direction of the wheel substrate 230 . For example, as shown in FIG. 4, the wheel member 221 is manufactured by cutting a disk-shaped wheel substrate 230 having a wavelength conversion layer 240 formed thereon along dotted lines. In other words, the wheel substrate piece 231 corresponds to a so-called fan-shaped portion obtained by cutting the wheel substrate 230 , and the segment 241 corresponds to a portion obtained by cutting the wavelength conversion layer 240 . When fixing the plurality of wheel members 221 with the wheel fixture 25 , when fixing the wavelength conversion wheel 21 to the shaft 24 with the wheel fixture 25 , the wheel fixture 25 can be fixed through the hole 28 .

In the present embodiment, each wheel member 221, each wheel substrate piece 231, and each segment 241 have the same size, but the present invention is not limited to this. The wheel member 221 may be combined to form a disk shape. In other words, the central angle (segment angle) of the sector in each wheel substrate piece 231 may be different, and the distance of the portion through which the excitation light passes may be different in each segment 241 .

In a general wavelength conversion wheel, the wavelength conversion layer is manufactured by coating or printing a wavelength conversion layer forming material containing a wavelength conversion material on a disc-shaped substrate. may cause problems. If such a problem occurs, there is a possibility that a light source device using this wavelength conversion wheel will not be able to obtain a desired irradiation intensity, and the product will be defective. The wavelength conversion wheel 21 of this embodiment is composed of a plurality of wheel members 221 . Therefore, by using a non-defective wheel member 221 when manufacturing the wavelength conversion wheel 21, the above problem can be avoided. In addition, since each wheel member 221 can be used by cutting a non-defective portion of the wavelength conversion wheel with the above-described defect, the final wavelength conversion wheel 21 is unlikely to be defective. , can improve the non-defective product rate.

If the light source device 100 is of a reflective type, the wheel substrate piece 231 is preferably made of metal such as aluminum, copper, or iron. In this case, it is preferable that the surface of the wheel substrate piece 231 is coated with a highly reflective film such as silver. Furthermore, the wheel substrate piece 231 may be made of a material that does not consider the reflection of the excitation light and the light emitted by the wavelength conversion material, and only the surface irradiated with the excitation light may be made of a reflective material.

If the light source device 100 is of a transmissive type, the wheel substrate piece 231 is preferably made of an inorganic material such as sapphire or glass that transmits the excitation light. Moreover, since the light emitted by the wavelength conversion material is radiated in all directions, it is preferable to reflect the light emitted by the wavelength conversion material while transmitting the excitation light when it is of a transmissive type. Further, the wheel substrate piece 231 preferably has a high thermal conductivity, regardless of whether it is of a reflective type or a transmissive type, in order to suppress temperature quenching of the wavelength conversion material. Therefore, the wheel substrate piece 231 is preferably made of aluminum or sapphire. Also, the wheel substrate piece 231 may be a combination of a reflective type and a transmissive type.

<Configuration example of wavelength conversion wheel>
Configuration examples of the wavelength conversion wheel will be described below with reference to FIGS.

<First configuration example>
FIG. 5 is a plan view showing a first configuration example of the wavelength conversion wheel.

The wavelength conversion wheel 21-1 includes, for example, a plurality of wheel members 221R, 221G and 221Y.

The wheel members 221R, 221G, and 221Y have, for example, a wheel substrate piece 231 and segments 241R, 241G, and 241Y, which are wavelength conversion layers arranged on the wheel substrate piece 231, respectively. The segments 241R, 241G, and 241Y are wavelength conversion layers that emit different colors of red, green, and yellow by excitation light. The wavelength conversion wheel 21-1 in this configuration example corresponds to, for example, the wavelength conversion wheel 21 shown in FIG.

In the wavelength conversion wheel 21-1, for example, the segments 241R, 241G, and 241Y are preferably arranged so that the segments of each color are present at a plurality of locations, and more preferably the number of segments of each color is the same. . In the circumferential direction of the wavelength conversion wheel 21-1, each color exists in a plurality of regions, and more particularly, each color has the same number. Although the wheel members 221R, 221G, and 221Y have the same size in FIG. 5, the sizes may be different, and the segment angles of the respective colors may be different.

<Second configuration example>
FIG. 6 is a plan view showing a second configuration example of the wavelength conversion wheel.

The wavelength conversion wheel 21-2 includes a plurality of wheel members 221 and translucent members 260, for example. A disk-shaped wavelength conversion wheel 21 is configured by a plurality of wheel members 221 and a translucent member 260 . The wavelength conversion wheel 21-2 in this configuration example corresponds to, for example, the wavelength conversion wheel 21 shown in FIG.

The wheel member 221 has, for example, a wheel substrate piece 231 and a segment 241 that is a wavelength conversion layer arranged on the wheel substrate piece 231 . In other words, it can be said that at least one of the plurality of segments in the wavelength conversion wheel 21-2 serves as a transmission portion through which the excitation light is transmitted.

The translucent member 260 is made of, for example, a transparent base material such as glass, and transmits excitation light. With this translucent member 260, the length of the wavelength conversion layer 24 through which the excitation light passes can be arbitrarily adjusted in the wavelength conversion wheel 21-2.

<Third configuration example>
FIG. 7 is a plan view showing a third configuration example of the wavelength conversion wheel.

The wavelength conversion wheel 21-3 in this configuration example corresponds to, for example, the wavelength conversion wheel 21 shown in FIG. That is, each wheel member 221 is fixed by the wheel fixture 25 with a space 270 between them.

When the wavelength conversion wheel 21-3 is irradiated with excitation light of high energy density, the energy that has not been wavelength-converted is converted into heat, and the temperature of the wavelength conversion wheel 21-3 rises. For example, when the wavelength conversion wheel is composed of an integral disc-shaped substrate, the stress generated by the difference in coefficient of thermal expansion between the substrate and the wavelength conversion layer is applied to the portion where the bonding strength between the substrate and the wavelength conversion layer is weakest. concentrate on However, in the wavelength conversion wheel 21-3 of this configuration example, since the wheel members 221 are spaced 270 from each other, the stress is dispersed, and failures such as peeling of the wavelength conversion layer can be prevented. .

The light source device 100 can be used, for example, in a projection device such as a projector.

(Configuration of projection device)
FIG. 8 shows a schematic diagram of an example of a projection device. The projection device 300 uses, for example, the light source device 100 described above.

The projection device 300 includes the wavelength conversion wheel rotating device 20 , a rotational position sensor 303 that acquires the rotational position of the wavelength conversion wheel 21 in the wavelength conversion wheel rotating device 20 , and the light source 30 based on output information from the rotational position sensor 303 . A light source control unit 304 for control, a display element 307, a light source side optical system 306 for guiding light from the wavelength conversion wheel rotating device 20 to the display element 307, and a projection for projecting projection light from the display element 307 onto a screen. A side optical system 308 is provided.

The projection device 300 controls the output of the light source 30 based on the rotational position information of the wavelength conversion wheel 21 acquired by the rotational position sensor 303 . The excitation light 31 emitted from the light source 30 is applied to the wavelength conversion layer of the wavelength conversion wheel 21 .

When a transmission portion is provided in a part of the wavelength conversion wheel 21, the blue excitation light 31 is transmitted through the wavelength conversion wheel 21 via the transmission portion. The excitation light 31 irradiated to the wavelength conversion layer can pass through the light source side optical system 306 and mirrors 309a to 309c on the optical path. The light source side optical system 306 is preferably a dichroic mirror. A preferred dichroic mirror can reflect blue light incident at 45 degrees and transmit red and green light.

In more detail, by adopting a dichroic mirror having the above optical characteristics in the light source side optical system 306, the blue light of the excitation light 31 incident on the dichroic mirror is reflected and directed to the wavelength conversion wheel 21. The blue light is transmitted through the wavelength conversion wheel 21 through the transmission portion according to the timing of the rotation of the wavelength conversion wheel 21 . Depending on the timing of the rotation of the wavelength conversion wheel 21, the excitation light 31 applied to areas other than the transmission portion is applied to the wavelength conversion layer and converted into light of different wavelengths. Red and green lights, which are lights with different wavelengths, pass through the dichroic mirror and enter the display element 307 . The blue light that has passed through the transmission portion enters the dichroic mirror again through the mirrors 309a to 309c, is reflected by the dichroic mirror again, and enters the display element 307. FIG.

In a preferred embodiment, the projector (projection device 300 ) can include the light source device 100 described above, a display element 307 , a light source side optical system 306 (dichroic mirror), and a projection side optical system 308 . A light source side optical system 306 (dichroic mirror) can guide light from the light source device 301 to the display element 307, and a projection side optical system 308 can project the projection light from the display element 307 onto a screen or the like. can. In a preferred embodiment, display element 307 is preferably a DMD (digital mirror device). The projection-side optical system 308 preferably consists of a combination of projection lenses.

The present disclosure is not limited to the above embodiments, and can be replaced with configurations that are substantially the same as the configurations shown in the above embodiments, configurations that achieve the same effects, or configurations that can achieve the same purpose. may

REFERENCE SIGNS LIST 100 light source device 10 optical system 11 dichroic mirror 13 biconvex lens 14 single convex lens 15 single convex lens 20 wavelength conversion wheel rotating device 21 wavelength conversion wheel 221 (221R, 221G, 221Y) wheel member 23 wheel substrate , 230 wheel substrate, 231 wheel substrate piece, 24 wavelength conversion layer, 240 wavelength conversion layer, 241 (241R, 241G, 241Y) segment, 25 wheel fixture, 26 rotating shaft, 27 driving device, 30 light source, 31 excitation light, 40 reflective layer 300 projection device 301 light source device 303 rotation position sensor 304 light source control unit 306 light source side optical system 307 display element 308 projection side optical system 309a mirror 309b mirror 309c mirror

Claims (13)

a plurality of wheel members;
a fixture that fixes the plurality of wheel members in a disc shape;
a wavelength conversion layer disposed on the plurality of wheel members;
A wavelength conversion wheel having a . Adjacent wheel members are adhered to each other with an adhesive,
A wavelength conversion wheel according to claim 1 . Adjacent wheel members are spaced apart and secured to each other.
A wavelength conversion wheel according to claim 1 . wherein the plurality of wheel members are adhesively secured to the fixture;
The wavelength conversion wheel according to any one of claims 1-3. The wavelength conversion layer is arranged along the circumferential direction of the wavelength conversion wheel,
A wavelength conversion wheel according to any one of claims 1-4. The wavelength conversion layer has a plurality of segments divided and arranged along the circumferential direction of the wavelength conversion wheel,
6. A wavelength conversion wheel according to claim 5. At least one of the plurality of segments is glass serving as a transmission portion that transmits excitation light,
7. A wavelength conversion wheel according to claim 6. The plurality of segments includes segments that emit fluorescence of different colors,
8. A wavelength conversion wheel according to claim 6 or 7. The segments that fluoresce in different colors are the same in number.
9. A wavelength conversion wheel according to claim 8. The segments that emit fluorescence of different colors each have a plurality of segments of each color,
10. A wavelength conversion wheel according to claim 8 or 9. A wavelength conversion wheel according to any one of claims 1 to 10;
a driving device for rotating the wavelength conversion wheel;
a light source that irradiates the wavelength conversion wheel with excitation light;
with
Fluorescence is emitted when excitation light is incident on the wavelength conversion layer;
Light source device. A light source device according to claim 11;
a display element;
a light source side optical system for guiding light from the light source device to the display element;
a projection-side optical system that projects the projection light from the display element onto a screen;
A projection device comprising: moreover,
a rotational position sensor that acquires the rotational position of the wavelength conversion wheel;
a light source control unit that controls the light source based on output information from the rotational position sensor;
comprising
13. Projection device according to claim 12.

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