JP5922026B2 - Light source module - Google Patents

Description

  The present invention relates to a light source module that combines and emits light from a plurality of light sources.

  2. Description of the Related Art Conventionally, an apparatus having a plurality of light sources and a structure that multiplexes light output from the light sources into a single unit is known. For example, Patent Document 1 discloses a laser display device that combines laser beams from three light sources arranged in parallel through an optical system such as a dichroic mirror.

  Patent Document 2 discloses a laser display in which three adjacent laser light sources are arranged at right angles, and the emitted light from the laser light sources is combined via an optical system such as a dichroic mirror and projected by a projector lens. An apparatus is disclosed.

Japanese Patent Laid-Open No. 2007-213078 Japanese Patent Laid-Open No. 11-064789

  However, in Patent Documents 1 and 2, the light emitted from each light source is multiplexed by aligning the optical axes with an optical system. For this reason, it is necessary to arrange | position the position of a light source so that the emission direction of another light source may not be shielded. Therefore, there is a problem that the arrangement of each light source is restricted and a space is taken in a direction perpendicular to the emission direction of the condensed light, and the shape of a device to which such a configuration is applied is restricted. .

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a light source module capable of saving space and reducing the limitation of the shape of a device to be applied.

  The light source module of the present invention is sequentially arranged so that at least a part thereof is on the same straight line, and a plurality of light sources that emit light in the arrangement direction and light emitted from the plurality of light sources are propagated respectively. Light that is arranged in the arrangement direction on the same line as the plurality of optical fibers and the plurality of light sources, multiplexes the light propagated by the plurality of optical fibers, and emits the combined light in the arrangement direction And a fiber type optical multiplexer.

  According to the said structure, the light from a several light source is propagated to an optical fiber type | mold optical multiplexer with an optical fiber. In general, since an optical fiber has bending resistance depending on the material or the like, it can be bent to reach an optical fiber type optical multiplexer. As a result, the light incident on the optical fiber from the light source is propagated directly to the optical fiber type optical multiplexer through the optical fiber, so that an optical system for performing reflection / diffraction or the like becomes unnecessary. Further, since the plurality of light sources are sequentially arranged on the same straight line, each light source can be miniaturized in a direction perpendicular to the light emission direction. As a result, space saving and restriction on the shape of the device to be applied can be reduced.

  Furthermore, since an optical fiber type optical multiplexer is used, light from the light source is propagated through the optical fiber, so that an optical system for performing reflection / diffraction is not required. Thereby, the optical axis shift due to expansion / contraction of the member due to temperature change or vibration from the outside does not occur. As a result, resistance to external environmental changes can be improved and quality can be stabilized.

  The light source module of the present invention accommodates the plurality of light sources, the plurality of optical fibers, and the optical fiber multiplexer, and includes at least two lid members, and the plurality of light sources and the light are formed by the lid members. You may further have the housing | casing which supports a fiber type multiplexer.

  According to the said structure, since each structure is accommodated in the state clamped by the housing | casing, the stable support can be performed.

  In the light source module of the present invention, the housing has a recess in which at least one lid member can fit at least one of the plurality of light sources and the optical fiber multiplexer. May be.

  According to the above configuration, since at least one of the plurality of light sources and the optical fiber type multiplexer is held in a state of being fitted inside the casing, further stable support can be performed.

  In the light source module of the present invention, the plurality of light sources may be configured to emit light having different wavelengths.

  According to the above configuration, the plurality of light sources can emit light having different wavelengths. Thereby, the light of various wavelengths can be combined and the applicable range of a light source module can be expanded.

  In the light source module of the present invention, the plurality of light sources may emit visible light.

  According to the above configuration, each of the plurality of light sources can emit visible light. Thereby, since visible light can be emitted, it can be applied to various devices such as lighting.

  In the light source module of the present invention, the plurality of light sources may be laser diodes that emit lasers having wavelengths corresponding to the RGB three primary colors.

  According to the above configuration, the plurality of light sources can emit lasers having wavelengths corresponding to the RGB three primary colors. As a result, the light intensity of the laser diode corresponding to each of the three primary colors can be adjusted to obtain a desired color for the light emitted from the optical fiber type optical multiplexer.

  In the light source module of the present invention, the three light sources and the first to third optical fibers for single mode transmission are arranged, and the optical fiber type optical multiplexer includes the first to third optical fibers. An optical multiplexer in which optical fibers are arranged in parallel with each other in this order when viewed from a cross-sectional direction orthogonal to the fiber axis direction, and the first optical fiber and the third optical fiber are not in contact with each other. Arranged in contact with only the second optical fiber, and of the first to third optical fibers, the first optical fiber and the second optical fiber have equal parameters, The third optical fiber has parameters different from those of the other two optical fibers, and the relationship between wavelengths of light incident from the three optical fibers is λ1 <λ2 <λ3. When the first optical The light having the wavelength of λ1 is incident on the lever, the light having the wavelength of λ2 is incident on the second optical fiber, and the light having the wavelength of λ3 is incident on the third optical fiber. The combined light of the light having the wavelengths of λ1, λ2, and λ3 may be emitted from the first optical fiber.

  According to said structure, the light of 3 wavelengths from a light source can be combined with the transmittance | permeability more than a fixed standard. Furthermore, since it is the structure which integrates three optical fibers, it is small.

  Further, the optical fiber of the light source module of the present invention emits light from the light source in the optical fiber type optical multiplexer, and the optical fiber type optical multiplexer has an emission end face of the optical fiber. The light emitted from the exit end face is incident between an exit end face facing the exit end face, and the exit end face and the entrance end face, and the light exited from the exit end face is incident on the entrance side. The structure which has a protective medium which consists of gel-like resin permeate | transmitted to an end surface may be sufficient.

  According to said structure, the protective medium which consists of gel-like resin interposes between the output end surface of an optical fiber, and the input end surface of an output side optical fiber. Therefore, even if the end surfaces of the optical fiber and the exit side optical fiber are rubbed due to vibration or the like, or the crimping load applied between the exit end surface of the optical fiber and the entrance end surface of the exit side optical fiber is increased, the protective medium itself Will not be damaged. As a result, it is possible to prevent deterioration of the transmission characteristics of the optical fiber type optical multiplexer due to the damage of the protective medium.

  The present invention can save space and limit the shape of a device to be applied.

It is a partially transparent perspective view which shows the light source module which concerns on embodiment of this invention. It is explanatory drawing which shows the positional relationship of the laser diode, optical fiber, and optical fiber type optical multiplexer in a light source module. It is a figure which shows the optical fiber type | mold optical multiplexer which concerns on embodiment of this invention. It is sectional drawing of the optical coupling part in the optical fiber type | mold optical multiplexer of FIG. It is a figure which shows the characteristic table | surface of the single mode optical fiber which comprises the optical fiber type | mold optical multiplexer which concerns on embodiment of this invention. It is a figure which shows the graph of a winding diameter when a red light injects into the single mode optical fiber which comprises an optical fiber type | mold optical multiplexer, and a bending loss. It is a figure which shows the structure table | surface of the optical fiber type | mold optical multiplexer in the comparative examples 1 and 2 and an Example. It is a figure which shows the graph of the wavelength with respect to the transmittance | permeability of the light radiate | emitted from the optical fiber type | mold optical multiplexer in the comparative example 1. FIG. It is a figure which shows the graph of the wavelength versus the transmittance | permeability of the light radiate | emitted from the optical fiber type | mold optical multiplexer in the comparative example 2. It is a figure which shows the graph of the wavelength with respect to the transmittance | permeability of the light radiate | emitted from the optical fiber type | mold optical multiplexer in an Example. It is a partial exploded perspective view of the light source module which concerns on embodiment of this invention. It is explanatory drawing which shows the modification of the positional relationship of the laser diode in a light source module, an optical fiber, and an optical fiber type optical multiplexer. It is explanatory drawing which shows the modification of the positional relationship of the laser diode in a light source module, an optical fiber, and an optical fiber type optical multiplexer. It is explanatory drawing which shows the modification which used the multimode optical fiber for the some optical fiber.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

(Light source module)
As shown in FIG. 1, the light source module 1 according to the present embodiment is sequentially arranged so that at least a part thereof is on the same straight line, and laser diodes 11 and 12 as light sources that emit light in the arrangement direction. 13 (first laser diode 11, second laser diode 12, third laser diode 13) and three optical fibers 21, 22, and 23 for propagating light emitted from the laser diodes 11, 12, and 13, respectively. Are arranged in the same arrangement direction as the laser diodes 11, 12, and 13, combine the light propagated by the three optical fibers 21, 22, and 23, and emit the combined light in the arrangement direction. And an optical fiber type optical multiplexer 30.

  The light source module 1 also accommodates three power supply cables 41, 42, 43, three laser diodes 11, 12, 13, three optical fibers 21, 22, 23, and an optical fiber type optical multiplexer 30. And a housing 50.

  Here, the “arrangement direction” is a direction in which a plurality of light sources at least part of which are arranged on the same straight line are arranged in a line, and is an emission direction of the light sources. Therefore, the next light source is arranged in the light emission direction of one light source. That is, the plurality of light sources are not arranged at positions where they are parallel to each other. In the present embodiment, the number of light sources is three, but is not limited to this. For example, the number may be two, or four or more.

  Further, “emitting in the arrangement direction” means, for example, that the second laser diode 12 emits from the light emitting position toward the direction from the first laser diode 11 toward the second laser diode 12. Yes.

  Next, each structure of the light source module 1 according to the present embodiment will be specifically described.

(light source)
FIG. 2 is an explanatory diagram showing the positional relationship of the configuration of the light source module 1 according to the present embodiment. As shown in FIG. 2, the laser diodes 11, 12, and 13 serving as light sources emit visible light having wavelengths corresponding to the three primary colors of RGB. Specifically, the first laser diode 11 emits blue light (first visible light), the second laser diode 12 emits red light (second visible light), and the third laser diode 13 emits green light. (Third visible light) is emitted.

  The laser diodes 11, 12, and 13 are disposed so as to be positioned on the same straight line indicated by a virtual line 100 (two-dot chain line). Specifically, the second laser diode 12 is disposed in the emission direction of the blue light emitted from the first laser diode 11, and emits red light in the same direction as the emission direction of the blue light. The third laser diode 13 is disposed in the direction of red light emitted from the second laser diode 12 and emits green light in the same direction as the direction of red light emission. That is, the laser diodes 11, 12, and 13 are arranged in series and arranged so that the emission direction of visible light is coaxial. An optical fiber type optical multiplexer 30 is disposed in the direction in which green light is emitted from the third laser diode 13. The arrangement of the laser diode and the optical fiber type optical multiplexer is not limited to this.

  Here, a specific configuration of the laser diodes 11, 12, and 13 will be described. Although not shown, the laser diode 11 includes a laser diode element, a CAN package, a lens, a lens barrel, a flange, and a ferrule.

  The laser diode element that emits blue light having a light intensity corresponding to the supplied voltage is covered with a cylindrical CAN package. In the cylindrical barrel fixed to the CAN package with an adhesive, a lens is provided at the end on the CAN package side so as to be coaxial with the emitted light. Thereby, the laser beam from the laser diode element is incident on the lens. The flange is provided with a through-hole for projecting one end of the optical fiber 21 inserted into the ferrule while being fitted with the ferrule projecting toward the lens barrel. One end of the ferrule is fitted to the flange and fixed with an adhesive, and the other end protruding from the flange is fitted to the lens barrel and fixed with an adhesive. The blue light collected by the lens is incident on the other end side of the optical fiber 21 inserted into the ferrule.

  Thereby, the blue light emitted from the first laser diode 11 is propagated by the optical fiber 21. Note that the configurations of the second laser diode 12 and the third laser diode 13 are the same as those of the first laser diode 11, and thus the description thereof is omitted.

  In the present embodiment, red light is light having a wavelength in the range of 600 nm to 700 nm. Green light is light having a wavelength in the range of 490 nm to 600 nm. Furthermore, blue light is light having a wavelength in the range of 400 nm to 500 nm. That is, the three laser diodes 11, 12, and 13 can emit visible light (laser light) having wavelengths corresponding to the three primary colors of blue (B), red (R), and green (G), respectively. It has become. In the present embodiment, the first laser diode 11 emits blue light, the second laser diode 12 emits red light, and the third laser diode 13 emits green light. However, the present invention is not limited to this. In addition, in the present embodiment, visible light in the above-described wavelength band is output although the values of the above-described wavelength bands differ depending on the purpose, for example, the wavelength bands of green light and blue light overlap. A laser diode is used for each.

(Optical fiber)
The optical fibers 21, 22, and 23 are single mode optical fibers, and propagate each visible light emitted from the laser diodes 11, 12, and 13 configured as described above to the optical fiber type optical multiplexer 30. As shown in FIG. 2, one end of each of the optical fibers 21, 22, and 23 is connected to the laser diodes 11, 12, and 13, and the other end is connected to the optical fiber type optical multiplexer 30.

  Specifically, one end of the optical fiber 21 is connected to the first laser diode 11, and the other end is connected to the optical fiber type optical multiplexer 30. The optical fiber 21 extends in the direction of emitting blue light from the first laser diode 11 and reaches the optical fiber type optical multiplexer 30. The optical fiber 21 is curved in a convex shape so as to follow the second laser diode 12 and the third laser diode 13. That is, the optical fiber 21 is disposed in a state of bypassing the second laser diode 12 and the third laser diode 13 at an intermediate position between the first laser diode 11 and the optical fiber type optical multiplexer 30.

  The optical fiber 22 has one end connected to the second laser diode 12 and the other end connected to the optical fiber type optical multiplexer 30. The optical fiber 22 extends in the direction of emitting red light from the second laser diode 12 and reaches the optical fiber type optical multiplexer 30. Note that the optical fiber 22 is curved in a convex shape along the third laser diode 13 to the side opposite to the direction in which the optical fiber 21 is curved. That is, the optical fiber 22 is disposed in a state of bypassing the third laser diode 13 at an intermediate position between the second laser diode 12 and the optical fiber type optical multiplexer 30.

  The optical fiber 23 has one end connected to the third laser diode 13 and the other end connected to the optical fiber type optical multiplexer 30. The optical fiber 23 extends in the direction of emitting green light from the third laser diode 13 and reaches the optical fiber type optical multiplexer 30.

  In this way, the laser diodes 11, 12, and 13 and the optical fiber type optical multiplexer 30 are connected by the optical fibers 21, 22, and 23, so that each visible light from the laser diodes 11, 12, and 13 can be emitted. Propagation to the fiber type optical multiplexer 30 is possible.

  The distance between the laser diodes 11, 12, and 13 may be determined according to the bending loss of the optical fiber. That is, when desired combined light cannot be obtained due to bending loss of the optical fiber due to bending, the fiber bend radius may be increased by widening the distance between the laser diodes 11, 12, and 13. Thereby, the fall of the performance of the light source module 1 can be prevented. In the present embodiment, the optical fibers 21, 22, and 23 are single-mode optical fibers, but are not limited to this.

(Optical fiber type optical multiplexer)
Thus, the optical fiber type optical multiplexer 30 connected to each of the optical fibers 21, 22, and 23 multiplexes the visible light propagated by the three optical fibers 21, 22, and 23, and combines the combined light with the third light. This is a three-wavelength optical multiplexer that emits to the opposite side of the laser diode 13.

  In the present embodiment, the optical fiber type optical multiplexer 30 is disposed in the direction in which green light is emitted from the third laser diode 13. That is, the optical fiber type optical multiplexer 30 is disposed at a position in series with the laser diodes 11, 12, and 13. The optical fiber type optical multiplexer 30 emits the combined light in the same direction as the visible light from the laser diodes 11, 12, and 13.

  Here, the specific configuration of the optical fiber type optical multiplexer 30, the manufacturing method, and the characteristics of the embodiment using the comparative example will be described.

(Configuration of optical fiber type optical multiplexer)
FIG. 3 is a schematic diagram showing the optical fiber type optical multiplexer 30. As shown in FIG. 3, the optical fiber type optical multiplexer 30 of the present embodiment includes a single mode optical fiber 31 as a first optical fiber, a single mode optical fiber 33 as a second optical fiber, and a third mode. A single mode optical fiber 32 is provided as an optical fiber.

  The three single mode optical fibers 31, 32, and 33 are arranged in parallel with each other, and the three single mode optical fibers 31, 32, and 33 are fused and stretched together at the optical coupling portion 36. The single mode optical fibers 31, 32, and 33 may be arranged in parallel with each other when viewed from the cross-sectional direction orthogonal to the fiber axis direction in the optical coupling portion. That is, the single mode optical fibers 31, 32, and 33 may be arranged on the same plane in the optical coupling section 36, or arranged on the same curved surface that is spirally twisted. Also good. Further, the single mode optical fiber 31 and the single mode optical fiber 32 are arranged in contact with only the single mode optical fiber 33 without contacting each other.

  The single mode optical fibers 31, 32, and 33 have ports through which light enters and exits. Specifically, the single mode optical fiber 31 has an incident port 31-1 into which light from the optical fiber 21 is incident and an output port 31-2 from which light is emitted. Similarly, the single mode optical fiber 33 receives the light from the optical fiber 23, and the single mode optical fiber 32 receives the light from the optical fiber 22. It has an entrance port 32-1 and an exit port 32-2. In addition, the exit port 33-2 and the exit port 32-2 are subjected to non-reflective processing by the termination portion 310. Further, as shown in FIG. 1, the single mode optical fiber 31 extends to the outside of the housing 50. That is, the combined light emitted from the light source module 1 (optical fiber type optical multiplexer 30) is propagated to the outside through the single mode optical fiber 31.

  Respective incident ports 31-1, 32-1, 33-1 of the single mode optical fibers 31, 32, 33 have different wavelengths propagated from the laser diodes 11, 12, 13 by the optical fibers 21, 22, 23. Light is incident on each. Specifically, red light is incident from the incident port 32-1 of the single mode optical fiber 32 located on the lower side in FIG. Green light is incident from the incident port 33-1 of the single mode optical fiber 33 located at the center in FIG. Also, blue light is incident from the incident port 31-1 of the single mode optical fiber 31 located on the upper side in FIG. The incident three colors of visible light are combined at the optical coupling unit 36, and the combined light is output from the output port 31-2. That is, the combined light output from the output port 31-2 becomes the combined light output from the light source module 1. Note that the exit ports 32-2 and 33-2 are subjected to a non-reflective treatment by the termination portion 310, thereby preventing reflection of the optical signal to the entrance port.

  Next, FIG. 4 is a cross-sectional view taken along line AA ′ relating to the optical coupling portion 36 of the optical fiber type optical multiplexer 30 shown in FIG. As shown in FIG. 4, the single mode optical fibers 31, 32, and 33 constituting the optical fiber type optical multiplexer 30 include a core 9 and a clad 8 formed around the core 9. The arrangement mode of the single mode optical fibers 31, 32, and 33 is not limited to this, and the single mode optical fiber 31 and the single mode optical fiber 32 do not contact each other, but each contact only with the single mode optical fiber 33. As long as they are arranged.

(Characteristics of single mode optical fiber of optical fiber type optical multiplexer)
The single mode optical fibers 31, 32 and 33 having the above-described configuration have characteristics as shown in the table of FIG. Here, in the case of this embodiment, the single mode optical fibers 31 and 33 have the same parameter, and the single mode optical fiber 32 has a parameter different from the other two. The parameters are parameters of the single mode optical fibers 31, 32, and 33. Specifically, the cladding diameter, the refractive index of the core, the refractive index of the cladding, the relative refractive index of the core and the cladding, the aperture Number (NA), secondary mode cutoff wavelength, etc.

  That is, in the case of this embodiment, single mode optical fibers having the same parameters are used for the single mode optical fibers 31 and 33, and different single mode optical fibers are used for the single mode optical fiber 32. . Specifically, single mode optical fiber A in FIG. 5 is used for single mode optical fibers 31 and 33, and single mode optical fiber B in FIG. 5 is used for single mode optical fiber 32.

  As shown in FIG. 5, the characteristics that greatly differ between the single mode optical fiber A and the single mode optical fiber B are the characteristics related to the wavelength. Specifically, the single mode optical fiber A has an operating wavelength of 445 to 600 nm and a secondary mode cutoff wavelength of 430 ± 15 nm. On the other hand, the single mode optical fiber B has an operating wavelength of 600 to 770 nm, a secondary mode cutoff wavelength of 570 ± 30 nm, and has a wavelength band higher than that of the single mode optical fiber A.

  Further, the single mode optical fiber A and the single mode optical fiber B having the above-described characteristics also have different characteristics with respect to bending loss. FIG. 6 is a graph showing a winding diameter versus bending loss graph when red light of 656 nm is incident on the single mode optical fiber A and the single mode optical fiber B constituting the optical fiber type optical multiplexer 30.

  As shown in FIG. 6, when red light of 656 nm is incident on the single mode optical fiber A and the single mode optical fiber B and the winding diameter is changed, the single mode optical fiber A has a diameter of about 20 mm. A bending loss of about 1 dB occurs, and a bending loss of 9 dB occurs with a diameter of 12 mm. On the other hand, in the single mode optical fiber B, bending loss does not occur even with a diameter of 12 mm. Therefore, in the optical multiplexer, when the single mode optical fiber B is used as the single mode optical fiber that receives the red light, the handling can be reduced, so that the single mode optical fiber can be accommodated in a smaller space.

(Manufacture of optical fiber type optical multiplexer)
Next, the fusion drawing method used when forming the optical coupling part 36 of the optical fiber type optical multiplexer 30 will be described. First, three single mode optical fibers 31, 32, and 33 having optical coupling sites are prepared. Next, the covering material that protected the clad 8 is removed only at the locations where the optical coupling portion 36 is formed. And it arrange | positions mutually parallel and contact | abuts each site | part for optical coupling in three single mode optical fiber 31,32,33. In this state, the optical coupling portion 36 of the optical fiber type optical multiplexer 30 of FIG. 3 is formed by stretching by the method described later while heating and melting the contact portion.

  Next, the stretching method will be described. Three single mode optical fibers 31, 32, and 33 are brought into contact with each other as described above. Then, the red light is incident from the incident port 32-1 of the single mode optical fiber 32 and is stretched while monitoring the emission power of the light emitted from the emission port 31-2 of the single mode optical fiber 31. Then, when the emission power of the light emitted from the emission port 31-2 reaches a desired value, the optical coupling unit 36 of the optical fiber type optical multiplexer 30 can be obtained by stopping the stretching.

  Here, the speed at the time of fusion drawing is 275 μm / second, and the drawing time is about 85 seconds. That is, the extension length of the optical coupling portion 36 is about 23.375 mm. Note that the wavelength of visible light incident from the incident ports 31-1, 32-1, 33-1 and the value of the output power when stopping the stretching are appropriately set according to the target transmittance and the wavelength at that time. can do.

  In the above-described fusion-stretching method, the case where red light is incident on the single mode optical fiber 32 has been described. This is because the wavelength of red light is the longest among the three colors of visible light, and the coupling curve is steep. Therefore, the optical coupling portion 36 of the optical fiber type optical multiplexer 30 with less optical variation can be formed by stopping the stretching when the emission power of the red light reaches a desired value. In the fusion stretching, not only red light but also green or blue light may be incident and monitored.

(Comparative Examples 1 and 2 and Examples of optical fiber type optical multiplexer)
Next, each characteristic is compared using the comparative examples 1 and 2 and the example of the optical fiber type optical multiplexer 30.

  FIG. 7 is a diagram showing a configuration table of the three-wavelength optical multiplexers in Comparative Examples 1 and 2 and the example. As shown in FIG. 7, in Comparative Example 1, optical fibers having the same parameters are used for the three single mode optical fibers 31, 32, and 33 constituting the optical fiber type optical multiplexer 30. Specifically, the single mode optical fiber A shown in FIG. 7 is used for the three single mode optical fibers 31, 32, and 33. Further, in the optical fiber type optical multiplexer 30 in Comparative Example 1, blue light is incident on the single mode optical fiber 31, green light is incident on the single mode optical fiber 33, and red light is incident on the single mode optical fiber 32. Light is incident.

  In Comparative Example 2, optical fibers having different parameters are used for the three single mode optical fibers 31, 32, and 33 constituting the optical fiber type optical multiplexer 30. Specifically, the single mode optical fiber 31 shown in FIG. 5 is used for the single mode optical fibers 31 and 32 of the comparative example 2, and the single mode optical fiber 33 shown in FIG. B is used.

  Further, the optical fiber type optical multiplexer 30 in the comparative example 2 is partially different from the light incident on the optical fiber type optical multiplexer 30 in the comparative example 1 and the example. That is, blue light is incident on the single mode optical fiber 31, red light is incident on the single mode optical fiber 33, and green light is incident on the single mode optical fiber 32.

  In the embodiment, the single mode optical fiber A shown in FIG. 5 is used for the single mode optical fibers 31 and 33, and the single mode optical fiber B shown in FIG. 5 is used for the single mode optical fiber 32. In addition, in the optical fiber type optical multiplexer 30 in the embodiment, blue light is incident on the single mode optical fiber 31, green light is incident on the single mode optical fiber 33, and red light is incident on the single mode optical fiber 32. Is incident.

  Here, the wavelength of the blue light incident on each optical fiber type optical multiplexer 30 is 446 nm, which is defined as λ1. The wavelength of green light is 532 nm, which is defined as λ2. The wavelength band of red light is 635 nm, which is defined as λ3. The secondary mode cutoff wavelength of the single mode optical fiber A is 434 nm, which is defined as C1. Further, the secondary mode cutoff wavelength of the single mode optical fiber B is 574 nm, which is defined as C2.

  In this case, the optical fiber type optical multiplexer 30 in the embodiment includes single mode optical fibers 31 and 33 having parameters that are equal to each other, and a single mode optical fiber 32 that has parameters different from the other two. When the relationship between the wavelengths of light (blue, green, red light) incident from the three single mode optical fibers 31, 33, 32 is λ1 <λ2 <λ3, the single mode optical fiber 31 Blue light having a wavelength of λ1 is incident, green light having a wavelength of λ2 is incident on the single mode optical fiber 33, and red light having a wavelength of λ3 is incident on the single mode optical fiber 32. , Λ1, λ2, and λ3 are combined and emitted from the single mode optical fiber 31.

  The optical fiber type optical multiplexer 30 in the embodiment includes a secondary mode cutoff wavelength C1 of the single mode optical fiber 31 and the single mode optical fiber 33, and a secondary mode cutoff wavelength C2 of the single mode optical fiber 32. The relationship with the wavelength λ3 of the red light incident from the single mode optical fiber 32 is C1 <C2 <λ3.

  On the other hand, in the optical fiber type optical multiplexer 30 in Comparative Example 1, the relationship between the wavelength of the light incident on each single mode optical fiber 31, 33, 32 and the secondary mode cutoff wavelength is C1 <λ1. , Λ2, and λ3. That is, in Comparative Example 1, the secondary mode cutoff wavelengths of all the single mode optical fibers 31, 33, 32 are smaller than the wavelength bands λ1, λ2, λ3 of the incident light.

  Similarly to the embodiment, the optical fiber type optical multiplexer 30 in the comparative example 2 includes single mode optical fibers 31 and 32 having the same parameters, and a single mode optical fiber 33 having parameters different from the other two. However, the light incident on the single mode optical fiber 33 and the single mode optical fiber 32 is opposite to that of the embodiment.

  Regarding the optical fiber type optical multiplexer 30 of the comparative examples 1 and 2 and the example having such a relationship, in the visible light incident on each of the incident ports 31-1, 32-1, and 33-1, the output port 31 is provided. FIG. 8 to FIG. 10 are graphs showing the transmittance with respect to the wavelength of light emitted from -2.

  When creating the wavelength versus transmittance graphs shown in FIGS. 8 to 10, light having different wavelengths is incident on the optical fiber type optical multiplexer 30 using a laser light source, and is emitted using an optical power meter. The light transmittance was measured at 6 points.

  FIG. 8 is a graph of wavelength versus transmittance in Comparative Example 1. As shown in FIG. 8, when only blue light is incident on the incident port 31-1, the light emitted to the output port 31-2 has an output peak value of nearly 80% at a blue wavelength of 446 nm. be able to. Further, when only red light is incident on the incident port 32-1, the light emitted to the output port 31-2 can obtain an output peak value of 100% at a red wavelength of 635 nm. However, when only green light is incident on the incident port 33-1, the light emitted to the emission port 31-2 can only obtain an emission peak value of about 40% at a green wavelength of 532 nm. , Well below the target standard transmittance of 60%.

  FIG. 9 is a graph of wavelength versus transmittance in Comparative Example 2. As shown in FIG. 9, when only blue light is incident on the incident port 31-1, the light emitted to the output port 31-2 has an output peak value of nearly 100% at a blue wavelength of 446 nm. be able to. However, when only red light is incident on the incident port 33-1, the light emitted to the output port 31-2 can obtain an output peak value of only about 10% at a red wavelength of 635 nm. Furthermore, even when only green light is incident on the incident port 32-1, the light emitted to the emission port 31-2 can obtain only about 10% of the emission peak value at 532 nm, which is the green point wavelength. It is not possible, and it is far below the target transmittance of 60%.

  On the other hand, FIG. 10 is a graph of wavelength versus transmittance in the example. As shown in FIG. 10, when only blue light is incident on the incident port 31-1, the light emitted to the output port 31-2 obtains an output peak value of 70% at a blue wavelength of 446 nm. Can do. In addition, when only red light is incident on the incident port 32-1, the light emitted to the output port 31-2 can obtain an output peak value of 70% or more at a red wavelength of 635 nm. Further, when only green light is incident on the incident port 33-1, the light emitted to the emission port 31-2 is at a reference wavelength of 60% or more at the emission peak value at a green wavelength of 532 nm. Can be obtained.

  From the above results, when the single mode optical fiber A having the same parameters is used for the single mode optical fibers 31, 32, and 33 constituting the optical fiber type optical multiplexer 30 as in Comparative Example 1, the green light The transmittance of this is much lower than the target standard of 60%.

  Further, as in Comparative Example 2, when blue light is incident on the single mode optical fiber 31, red light is incident on the single mode optical fiber 33, and green light is incident on the single mode optical fiber 32, the green color The transmittance of light and red light is significantly deteriorated.

  On the other hand, the single mode optical fiber A having the same parameter is used for the single mode optical fibers 31 and 33 and the single mode optical fiber B having a parameter different from the other two is used for the single mode optical fiber 32 as in the embodiment. In addition, when blue light is incident on the single mode optical fiber 31, green light is incident on the single mode optical fiber 33, and red light is incident on the single mode optical fiber 32, the light is incident as a result. In addition, it is possible to multiplex light of three wavelengths with a transmittance equal to or higher than a target reference (60%).

  As described above, in order to multiplex light having different wavelengths incident on the three single-mode optical fibers 31, 32, and 33, particularly red, blue, and green light, with a transmittance of a certain standard (60%) or more. For this, the configuration and arrangement of the single mode optical fibers 31, 32, and 33 as in the above-described embodiment are required.

(Power supply cable)
The laser diodes 11, 12, and 13 that emit the visible lights combined as described above are driven by power supplied from the three power supply cables 41, 42, and 43.

  As shown in FIG. 1, the three power supply cables 41, 42, and 43 are provided with laser diodes 11, 12, and 13 housed inside the housing 50 and the laser diodes 11, 12, and 13 provided outside the housing 50. 13 is connected to a drive unit (not shown) that independently controls the drive. The power supply cables 41, 42, and 43 each have a signal line and a ground line. The driving section supplies power to the laser diodes 11, 12, and 13 and can adjust the light intensity of each of the laser diodes 11, 12, and 13 by changing the voltage value.

  The power supply cables 41, 42, and 43 extend from the laser diodes 11, 12, and 13 to an external control unit through an opening formed in the housing 50. The power supply cables 41, 42, and 43 may be supported so as to be sandwiched between the inner wall of the housing 50 and the laser diodes 11, 12, and 13. Thereby, the power supply cables 41, 42, and 43 can be fixed. In the present embodiment, the power supply cables 41, 42, and 43 are formed by integrally forming round signal lines and ground lines, but are not limited thereto. For example, the power supply cable may be FPC (flexible printed circuit board) or FFC (flexible flat cable).

(Casing)
As described above, the housing 50 accommodates the laser diodes 11, 12, 13, the optical fibers 21, 22, 23 and the optical fiber type optical multiplexer 30. FIG. 11 is a partially exploded perspective view of the light source module 1. As shown in FIG. 11, the housing 50 includes two lid members 51 and 52, and the laser diodes 11, 12, and 13 and the optical fiber type optical multiplexer 30 are sandwiched and supported by the lid members 51 and 52.

  Specifically, the lid member 51 is formed with a recess 51a into which the laser diodes 11, 12, 13 and the optical fiber type optical multiplexer 30 are fitted. The laser diodes 11, 12, and 13 and the optical fiber type optical multiplexer 30 are fitted in the recess 51 a so that at least a part of the side surface in the direction perpendicular to the longitudinal direction of the housing 50 is in contact with the inner wall of the housing 50. Combined. Accordingly, the movements of the laser diodes 11, 12, and 13 and the optical fiber type optical multiplexer 30 are restricted in a direction perpendicular to the longitudinal direction of the housing 50.

  The housing 50 has the open surfaces of the lid member 51 and the lid member 52 in a state where the laser diodes 11, 12, and 13 and the optical fiber type optical multiplexer 30 are fitted in the recess 51 a of the lid member 51. The lid member 51 and the lid member 52 are fixed by screwing screws into the screw holes formed in the lid member 51 and the lid member 52. Accordingly, the laser diodes 11, 12, and 13 and the optical fiber type optical multiplexer 30 are supported in a state of being sandwiched between the lid member 51 and the lid member 52.

  In addition, the housing | casing 50 is not limited to this aspect. For example, at a location corresponding to a position between the locations supporting the laser diodes 11, 12, and 13 and the location supporting the optical fiber type optical multiplexer 30, for example, it has a bellows structure or is deformed It may be formed to be bendable by being formed of a material such as a resin that can be used. Thereby, it can match with the shape of the apparatus to apply, and space saving and size reduction can be achieved.

(Outline of the light source module 1)
As described above, the light source module 1 is sequentially arranged so that at least a part thereof is on the same straight line, and a plurality of light sources (laser diodes 11, 12, and 13) that emit light in the arrangement direction, A plurality of optical fibers (optical fibers 21, 22, 23) for propagating light emitted from each light source, and disposed in the same arrangement direction as the plurality of light sources and propagated by the plurality of optical fibers An optical fiber type optical multiplexer (optical fiber type optical multiplexer 30) that combines the light and emits the combined light in the arrangement direction is configured.

  According to the above configuration, visible light from a plurality of light sources is propagated to the optical fiber type optical multiplexer by the optical fiber. In general, since an optical fiber has bending resistance depending on the material or the like, it can be bent to reach an optical fiber type optical multiplexer. As a result, the light incident on the optical fiber from the light source is propagated directly to the optical fiber type optical multiplexer through the optical fiber, so that an optical system for performing reflection / diffraction or the like becomes unnecessary. Further, since the plurality of light sources are sequentially arranged on the same straight line, each light source can be miniaturized in a direction perpendicular to the light emission direction. As a result, space saving and restriction on the shape of the device to be applied can be reduced.

  Furthermore, since an optical fiber type optical multiplexer is used, visible light from the light source is propagated through the optical fiber, so that an optical system for performing reflection / diffraction is not required. Thereby, the optical axis shift due to expansion / contraction of the member due to temperature change or vibration from the outside does not occur. As a result, resistance to external environmental changes can be improved and quality can be stabilized.

  The light source module 1 accommodates three light sources, three optical fibers, and the optical fiber type multiplexer, and includes two lid members (lid members 51 and 52). It further has a housing (housing 50) that sandwiches and supports the optical fiber type multiplexer. Thereby, since each structure is accommodated in the state clamped by the housing | casing, stable support can be performed.

  Moreover, the housing | casing of the light source module 1 has a hollow (dent 51a) in which at least 1 lid member can fit at least one of three light sources and an optical fiber type multiplexer. Thereby, the more stable support can be performed.

  The light source module 1 is a laser diode in which a plurality of light sources emit visible light lasers having different wavelengths corresponding to the three primary colors of RGB. Thereby, the light of various wavelengths can be combined and the applicable range of a light source module can be expanded. Moreover, since visible light can be emitted, it can be applied to various devices such as lighting. Furthermore, by adjusting the light intensity of the laser diode corresponding to each of the three primary colors, a desired color can be obtained for the light emitted from the optical fiber type optical multiplexer.

(Modification)
The embodiments of the present invention have been described above, but only specific examples have been illustrated, and the present invention is not particularly limited. Specific configurations and the like can be appropriately changed in design. In addition, the actions and effects described in the embodiments of the present invention only list the most preferable actions and effects resulting from the present invention, and the actions and effects according to the present invention are described in the embodiments of the present invention. It is not limited to things.

  For example, in the present embodiment, the light incident from the incident ports 31-1, 33-1 and 32-1 of the three single mode optical fibers 31, 32, and 33 are blue, green, and red, respectively. It is not necessary to be limited to this. Any wavelength may be used as long as it corresponds to the wavelength and the secondary mode cutoff wavelength as shown in the embodiment of FIG.

  In the present embodiment, the certain standard of the output power is the transmittance of 60%, but it is not necessary to be limited to this, and it may be larger than 60% or smaller than 60%.

  In the present embodiment, as shown in FIG. 2, the laser diodes 11, 12, and 13 and the optical fiber type optical multiplexer 30 are arranged in a line on the same straight line indicated by the virtual line 100. However, it is not limited to this.

  For example, as shown in FIG. 12, the laser diodes 11, 12, and 13 and the optical fiber type optical multiplexer 30 have a configuration in which at least a part is disposed on the same straight line indicated by the virtual line 100. May be. That is, as compared with the previous embodiment, the laser diodes 11 and 12 may be arranged so as to be shifted in the bending direction of the optical fibers 21 and 22, respectively. As a result, it is possible to reduce the loss of the propagated laser by reducing the curvature of the optical fibers 21 and 22 while reducing the size.

  Moreover, in this embodiment, as shown in FIG. 2, it was the structure which has the three laser diodes 11 * 12 * 13, However, It is not limited to this. For example, as shown in FIG. 13, a configuration having two laser diodes 12 and 13 and two optical fibers 22 and 23 for propagating light emitted therefrom may be used. Thus, when there are two light sources, the optical fiber type optical multiplexer 130 illustrated in FIG. 13 may have two inputs and one output, or may have three inputs and one output. When the optical fiber type optical multiplexer 130 has three inputs and one output, any two inputs out of the three inputs may be used. Moreover, the structure which has a several optical fiber corresponding to four or more laser diodes and four or more laser diodes may be sufficient.

  In the present embodiment, the three laser diodes 11, 12, and 13 all emit visible light having different wavelengths, but the present invention is not limited to this. For example, at least two or more of the plurality of light sources, or all the light sources may have the same wavelength. The light emitted from the light source is not limited to visible light.

  In the present embodiment, the optical fibers 21, 22, and 23 are single mode optical fibers, but are not limited thereto. For example, the plurality of optical fibers may be multimode optical fibers. Hereinafter, modifications of the present embodiment using a multimode optical fiber will be described.

  FIG. 14 is an explanatory diagram showing a modification in which a multimode optical fiber is used for a plurality of optical fibers. As shown in FIG. 14, the light source module 201 of this modification is sequentially arranged so that at least a part thereof is on the same straight line, and four light sources 210a, 210b, 210c, which emit light in the arrangement direction. 210d, four incident-side optical fibers 220, 220, 220, and 220 for propagating light emitted from the four light sources 210a, 210b, 210c, and 210d, respectively, and the same as the four light sources 210a, 210b, 210c, and 210d Light that is arranged in a linear arrangement direction and that combines the light propagated by the four incident-side optical fibers 220, 220, 220, and 220, which are multimode optical fibers, and emits the combined light in the arrangement direction A fiber type optical multiplexer 230.

  As shown in FIG. 14, the optical fiber type optical multiplexer 230 includes four incident-side optical fibers 220 that emit incident light from the exit end face, and an entrance that faces the exit light from the exit end face. An exit-side optical fiber 221 that is incident from the end face; and a protective medium 250 that is interposed between the exit end face and the entrance end face and is made of a gel-like resin that transmits light emitted from the exit end face to the entrance end face. In the description of the optical fiber type optical multiplexer 230 according to the present modification, “incident” indicates incidence to the optical fiber type optical multiplexer 230, and “outgoing” means emission from the optical fiber type optical multiplexer 230. Indicates.

  In addition, the optical fiber type optical multiplexer 230 includes an incident side optical member 213 that accommodates the incident side optical fiber 220, an emission side optical member 223 that accommodates the emission side optical fiber 221, and an emission end face of the incident side optical fiber 210. A holding member 232 that holds the incident-side optical member 213 and the emitting-side optical member 223, and the incident-side optical member 213, the emitting-side optical member 223, and the holding member 232 so as to face the incident end face of the emitting-side optical fiber 221. The holding member 232 is stored in the holding case 233 without being in contact with the holding case 233.

  The four incident side optical fibers 220 are multimode optical fibers, and the four incident side optical fibers 220 are bundled in the optical fiber type optical multiplexer 230. Therefore, it is possible to couple light having the same wavelength, different wavelengths, or different output powers. Further, it can be easily connected to a light source and can be connected to a high power light source having a large light emitting area. Each incident-side optical fiber 220 has a core that is a light path in the center, and is configured so that a thin clad is covered on the peripheral surface thereof. The bundled four incident-side optical fibers 220 are bonded and fixed with an adhesive, and are accommodated in a through hole formed at the center of the incident-side optical member 213. The adhesive is formed of a material having a transmittance of 50% or more at a wavelength of 400 nm, a glass transition temperature of 130 ° C. or more, and a Shore hardness of 80 or more, and the four incident-side optical fibers 220. The incident side optical fiber 220 and the inner surface of the incident side optical member 213 are bonded and fixed together. Here, the reason why the adhesive having the above characteristics is used is that if the transmittance is less than 50%, the adhesive absorbs the leaked light and generates heat, and the deterioration is accelerated. Further, if the glass transition temperature of the adhesive is lower than 130 ° C., the glass transition temperature may be exceeded due to the temperature rise, and as a result, the transmittance of the optical fiber type optical multiplexer 230 decreases due to a change in physical properties of the adhesive. there is a possibility. In addition, if the shore hardness of the adhesive is less than 80, it will be excessively shaved during the polishing process in the manufacturing process, resulting in dents, dust adhering to that part, and light scattering at the dents. This is because of this.

  The output side optical fiber 221 is composed of a single multimode optical fiber, and has a core that is a light path at the center, like the incident side optical fiber 220, and a thin clad on the peripheral surface thereof. Covering. The exit-side optical fiber 221 is housed in a through hole formed in the center of the exit-side optical member 223, and an adhesive filled in the gap between the exit-side optical fiber 221 and the inner surface of the exit-side optical member 223. Bonded and fixed. The core diameter of the exit side optical fiber 221 is set larger than the core diameter of the entrance side optical fiber 220. More specifically, the respective core diameters are set so that all the core regions of the four incident side optical fibers 220 are included in the core region of the emission side optical fiber 221. This is because the light emitted from the core of the incident side optical fiber 220 is converted into the core of the output side optical fiber 221 during optical coupling between the output end surface of the incident side optical fiber 220 and the incident end surface of the output side optical fiber 221. This is for transmission with low loss. Further, the numerical aperture (NA) of the emission side optical fiber 221 is set to be equal to or larger than the numerical aperture (NA) of the incident side optical fiber 220. Thereby, the light emitted from the incident side optical fiber 220 is transmitted into the emission side optical fiber 221 with low loss.

  The entrance side optical fiber 220 and the exit side optical fiber 221 are arranged so that the exit end face of the entrance side optical fiber 220 and the entrance end face of the exit side optical fiber 221 face each other as shown in the enlarged portion 235 of FIG. Has been placed. A protective medium 250 is interposed between the incident side optical fiber 220 and the output side optical fiber 221.

  The protective medium 250 is made of a gel-like resin that transmits light emitted from the emission end face of the incident side optical fiber 220 to the incident end face of the emission side optical fiber 221. Since the protective medium 250 is provided so as to completely cover the exit end face of the entrance side optical fiber 220 and the entrance end face of the exit side optical fiber 221, a space 240 between the entrance side optical fiber 220 and the exit side optical fiber 221 is provided. There is no air layer. Therefore, the light input from the incident side optical fiber 10 chemically reacts with a silicon compound in the air to form SiO 2, and the SiO 2 is formed on the outgoing end face of the incident side optical fiber 220 and the incoming end face of the outgoing side optical fiber 221. Does not adhere, and the light transmission characteristics are not deteriorated. Further, since the protective medium 250 is a gel-like resin, it has a high viscosity. Specifically, for the protective medium 250, a resin having a miscibility (JISK2220) of 300 is used. Here, depending on the usage condition of the optical fiber type optical multiplexer 230, vibration or the like may occur. When the protective medium 250 is a film body formed by vapor deposition or ion assist on at least one of the exit end face of the entrance side optical fiber 220 and the entrance end face of the exit side optical fiber 221, a so-called solid material is formed on both. The protected protective media may collide with each other by vibration or rub against each other, and the protective media themselves may be damaged. In that respect, in the optical fiber type optical multiplexer 230, a protective medium 250 made of a gel-like resin is interposed between the exit end face of the entrance side optical fiber 220 and the entrance end face of the exit side optical fiber 221. For this reason, the end faces of the incident side optical fiber 220 and the outgoing side optical fiber 221 are rubbed due to vibration or the like, and the pressure load applied between the outgoing end face of the incident side optical fiber 220 and the incident end face of the outgoing side optical fiber 221 is large. Even if it happens, the protective medium 250 itself is not damaged. Thereby, it is possible to prevent deterioration of the transmission characteristics of the optical fiber type optical multiplexer 230 due to the damage of the protective medium 250.

  The protective medium 250 is a gel-like resin made of silicone having a small refractive index difference between the incident side optical fiber 220 and the output side optical fiber 221. Specifically, a gel-like resin made of silicone having a refractive index nD25 of 1.448 to 1.475 and a transmittance of 95% or more at a wavelength of 400 nm is used for the protective medium 250. In addition, since silicone is excellent in heat resistance, the protective medium 250 hardly changes even when the temperature rises, and the light resistance is also excellent, so that the refractive index and transmittance of the protective medium 250 hardly change.

  The holding member 232 that holds the incident side optical member 213 and the emission side optical member 223 so that the emission end face of the incidence side optical fiber 220 and the incidence end face of the emission side optical fiber 221 are opposed to each other is a hollow cylindrical split sleeve. It is. Specifically, the holding member 232 comes into close contact with the outer peripheral surfaces of the incident side optical member 213 and the emission side optical member 223 press-fitted into the holding member 232, so that the incident side optical member 213 and the emission side optical member are in contact with each other. The member 223 is held. The material of the holding member 232 is zirconia. Since zirconia tends to emit light to the outside, the light leaked through the incident side optical member 213 and the emission side optical member 223 is directly emitted to the outside. On the other hand, in the case of a metal sleeve such as nickel, it is difficult to emit leaked light to the outside, so that all the light enters the adhesive of the incident side optical fiber 220, the incident side optical member 213, and the output side optical member 223. As a result, the internal temperature rises and the adhesive deteriorates. In that respect, since the holding member 232 is made of zirconia, leakage light is emitted to the outside, and an increase in internal temperature can be prevented.

  The incident side optical member 213 is integrally configured by press-fitting a zirconia capillary 215 into a stainless steel flange 214. A through hole is formed in the flange 214 and the capillary 215, and the incident side optical fiber 220 passed through the protective tube 212 is inserted into the through hole from the flange 214 side. The incident side optical fiber 220 inserted into the incident side optical member 213 as described above is bonded and fixed by an adhesive filled in the incident side optical member 213. The flange 214 is housed in contact with the inner wall of the holding case 233, holds the holding member 232 without contacting the holding case 233, and holds heat generated inside the incident side optical member 213. It has a role of radiating heat to the case 233. Further, the end face of the incident side optical member 213 (end face of the capillary 215) is polished in a planar shape together with the emission end face of the incident side optical fiber 220. Here, when the exit end face of the incident side optical fiber 220 is not polished in a flat shape, the exit end face has a curved surface, so that it cannot be physically contacted with the entrance end face 240 of the exit side optical fiber 221. In some cases, the exit end face of the incident side optical fiber 220 is disposed. Then, the light from the incident side optical fiber 220 arranged at such a location is emitted obliquely toward the incident end face of the emission side optical fiber 221, and 240 between the incident end face of the emission side optical fiber 221. There is a risk of optical loss. However, since the exit end face of the incident side optical fiber 220 is polished flat as described above, the light emitted from the exit end face of the entrance side optical fiber 220 goes straight to the entrance end face of the exit side optical fiber 221. Is transmitted. Thereby, the light from the incident side optical fiber 220 can be transmitted into the emission side optical fiber 221 with low loss.

  As shown in FIG. 14, the emission-side optical member 223 is integrally formed by press-fitting a zirconia capillary 225 into a stainless steel flange 224. A through hole is formed inside the flange 224 and the capillary 225, and the emission side optical fiber 221 passed through the protective tube 222 is inserted into the through hole from the flange 224 side. The exit-side optical fiber 221 inserted into the exit-side optical member 223 as described above is bonded and fixed by an adhesive filled in the exit-side optical member 223. The flange 224 is housed so that the lower end is in contact with the inner wall of the holding case 233, holds the holding member 232 without contacting the holding case 233, and is generated inside the emission side optical member 223. It has a role of radiating heat to the holding case 233. Further, the flange 224 is connected to the emission side inner wall of the holding case 233 by a spring 234. The spring 234 connects between the flange 224 and the holding case 233, and the biasing force keeps the distance between the end surface of the incident side optical member 213 and the end surface of the output side optical member 223 constant. Here, the distance between the end face of the incident side optical member 213 and the end face of the exit side optical member 223 is also adjusted by the viscosity of the protective medium 250 interposed therebetween. The protective medium 250 is made of a resin having a miscibility (JISK2220) of 300, and the distance between the end surface of the incident side optical member 213 and the end surface of the output side optical member 223 is adjusted together with the biasing force of the spring 234. The In addition, the end face of the exit-side optical member 223 (end face of the capillary 225) is polished in a planar shape together with the entrance end face of the exit-side optical fiber 221 in the same manner as the exit end face of the entrance-side optical fiber 220.

  As shown in FIG. 14, such an optical fiber type optical multiplexer 230 has light sources 210 a, 210 b, 210 c, and 210 d connected to incident side light on the tip ferrules 216 provided at the respective tips of the incident side optical fibers 220. Connection is made via a fiber 220. From the light sources 210a, 210b, 210c, and 210d, for example, light having the same wavelength, different wavelengths, or different output powers are output. The light transmitted through the incident side optical fiber 220 is coupled to the output side optical fiber 221 at a space 240 between the incident side optical fiber 220 and the output side optical fiber 221. Further, the combined light is transmitted through the emission side optical fiber 221 and output to a device connected to the tip ferrule 226 provided at the tip of the emission side optical fiber 221. As described above, by combining the light from the light sources 210a, 210b, 210c, and 210d using the optical fiber type optical multiplexer 230, it is possible to output power-coupled or wavelength-coupled light. . If the incident side optical fiber 220 is smaller in diameter than, for example, a standard optical fiber, and if it is desired to use components and equipment that are applied to the standard optical fiber, the incident side optical fiber 220 is used. A standard optical fiber may be fused to the tip of the wire. In other words, the incident-side optical fiber 10 may be converted from the incident-side optical fiber 10 to a standard optical fiber by fusion so as to be compatible with components and devices applied to the standard optical fiber.

DESCRIPTION OF SYMBOLS 1 Light source module 11 1st laser diode 12 2nd laser diode 13 3rd laser diode 21 * 22 * 23 Optical fiber 30 Optical fiber type optical multiplexer 41 * 42 * 43 Power supply cable 50 Case 51 * 52 Cover member 51a Dimple

Claims (6)

A plurality of light sources arranged sequentially so that at least a part thereof is on the same straight line, and emitting light in the arrangement direction;
A plurality of optical fibers that respectively propagate the light emitted from the plurality of light sources;
An optical fiber type optical multiplexer that is arranged in the arrangement direction on the same straight line as the plurality of light sources, multiplexes the light propagated by the plurality of optical fibers, and emits the combined light in the arrangement direction; Have
The number of the plurality of light sources is three;
The plurality of optical fibers are first to third optical fibers that perform single mode transmission,
The three light sources and the first to third optical fibers are disposed;
The optical fiber type optical multiplexer is:
An optical multiplexer in which the first to third optical fibers are arranged in parallel with each other in this order as seen from the cross-sectional direction orthogonal to the fiber axis direction,
The first optical fiber and the third optical fiber are arranged in contact with only the second optical fiber without contacting each other,
Of the first to third optical fibers, the first optical fiber and the second optical fiber have secondary mode cutoff wavelengths that are equal to each other, and the third optical fiber is the other two. A second-order mode cutoff wavelength different from that of the optical fiber,
When the relationship between the wavelengths of light incident from the three optical fibers is λ1 <λ2 <λ3, light having the wavelength of λ1 is incident on the first optical fiber, and the second The light having the wavelength of λ2 is incident on the optical fiber, the light having the wavelength of λ3 is incident on the third optical fiber, and the combined light of the light having the wavelengths of λ1, λ2, and λ3 is The light source module is emitted from the first optical fiber. The light source module according to claim 1, wherein each of the plurality of light sources emits light having a different wavelength. Wherein the plurality of light sources, a light source module according to claim 1 or 2, characterized in that emits visible light. 2. The light source module according to claim 1, wherein the plurality of light sources are laser diodes that emit lasers having wavelengths corresponding to RGB three primary colors. The plurality of light sources, the plurality of optical fibers, and the optical fiber type optical multiplexer are accommodated, and include at least two lid members, and the plurality of light sources and the optical fiber type optical multiplexer are sandwiched by the lid members. the light source module according to any one of claims 1 to 4, characterized in that it further includes a support to the housing. Wherein the housing, at least one of said cover member, according to claim, characterized in that it has a fittable recesses at least one of the plurality of light sources and the optical fiber-type optical multiplexer 5 The light source module according to 1.

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