Semiconductor laser assembly with thin film lithium composite waveguide

Abstract

The invention relates to a semiconductor laser assembly with a thin film lithium composite waveguide. A semiconductor laser assembly comprising: an array of surface emitting lasers having a light emitting surface and an opposing surface; at least one electrical contact electrically connected to provide an electrical bias from an external power source to the array of surface emitting lasers; and an optical waveguide over the light emitting surface. The optical waveguide includes lithium.

Description

Technical Field

[0001] The present application relates generally to laser components and, more particularly, to semiconductor laser components. Background Art

[0002] Visible lasers emitting in the red, green, and blue spectrum (RGB) are widely used in medical applications, such as tissue penetration for diagnosis and treatment. They are also used for projection in screens and displays (including AR / VR displays). In addition, RGB lasers are used in applications that require white light, such as headlights. As a result, for RGB applications, compact RGB laser sources that can be manufactured in large quantities, such as VCSELs, are highly desired.

[0003] Currently, most of the available compact RGB solutions are based on LED sources. One disadvantage of current solutions based on LED sources includes the lack of a wide color gamut for projectors / displays. Another disadvantage includes poor beam quality, which is detrimental to many medical applications. In addition, LEDs typically have a much wider divergence angle than lasers and, contrary to lasers, do not have coherence. Both features lead to severe losses when delivering light energy to tissue. Another downside of using LEDs is their low modulation bandwidth, which is required for applications that require short pulse widths.

[0004] Currently available RGB laser technology has much larger size than VCSEL. Gallium nitride based RGB VCSELs reported in the literature have not proven to be sufficiently reliable and have low efficiency.

[0005] Accordingly, those skilled in the art continue to conduct research and development in the field of semiconductor laser components. Summary of the invention

[0006] A semiconductor laser assembly is disclosed.

[0007] In one example, a semiconductor laser assembly includes: an array of surface emitting lasers having a light emitting surface and an opposing surface; at least one electrical contact electrically connected to provide an electrical bias from an external power source to the array of surface emitting lasers; and an optical waveguide above the light emitting surface, wherein the optical waveguide includes lithium. The at least one electrical contact may include: one contact on the light emitting surface and another contact on the opposing surface, or a pair of contacts on the opposing surfaces.

[0008] The optical waveguide may comprise lithium niobate or lithium tantalate. The optical waveguide may be periodically poled by 180°.

[0009] The array of surface emitting lasers may include a plurality of vertical cavity surface emitting lasers or a plurality of photonic crystal surface emitting lasers. The array of surface emitting lasers may include top emitting lasers or bottom emitting lasers. The array of surface emitting lasers may include one or more of the following: an emitter configured to emit electromagnetic radiation of a wavelength between 1850nm and 1950nm; an emitter configured to emit electromagnetic radiation of a wavelength between 1200nm and 1300nm; an emitter configured to emit electromagnetic radiation of a wavelength between 1000nm and 1100nm; an emitter configured to emit electromagnetic radiation of a wavelength between 900nm and 1000nm; an emitter configured to emit electromagnetic radiation of a wavelength between 1500nm and 1600nm.

[0010] The array of surface emitting lasers may include at least one emitter having a polarization aligned with the width of the optical waveguide and / or at least one emitter having a polarization perpendicular to the width of the optical waveguide.

[0011] The semiconductor laser assembly may also include a semi-insulating substrate positioned between the surface emitting laser and the optical waveguide. The semi-insulating substrate may include gallium arsenide (GaAs). The semiconductor laser assembly may also include a beam combiner positioned between the array of surface emitting lasers and the optical waveguide. The semiconductor laser assembly may also include an anti-reflection coating on the optical waveguide.

[0012] A method for emitting electromagnetic radiation is also disclosed.

[0013] In one example, the method includes coupling an optical waveguide including lithium with a semiconductor laser; and emitting electromagnetic radiation of a first wavelength from the semiconductor laser to the optical waveguide, wherein electromagnetic radiation of a second wavelength is emitted from the optical waveguide, and wherein the second wavelength is shorter than the first wavelength.

[0014] The coupling may include combining or regrowth. In one example, the emitting may include emitting electromagnetic radiation of a wavelength between 1200 nm and 1300 nm from the semiconductor laser to the optical waveguide, whereby the frequency is doubled or substantially doubled when passing through the optical waveguide. In another example, the emitting may include: emitting electromagnetic radiation of a first wavelength from a first emitter of the semiconductor laser to a beam combiner; emitting electromagnetic radiation of a second wavelength from a second emitter of the semiconductor laser to the beam combiner; and emitting electromagnetic radiation of the first wavelength and the second wavelength from the beam combiner to the optical waveguide, where the optical waveguide adds the first wavelength and the second wavelength when passing through the optical waveguide.

[0015] Other examples will become apparent from the following detailed description, drawings, and appended claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The present disclosure will be described with reference to the following drawings, wherein like reference numerals identify like parts throughout.

[0017] Figure 1 is a schematic cross-sectional view of an upward or top emitting semiconductor laser assembly;

[0018] Figure 2 is a schematic cross-sectional view of a downward or bottom emitting semiconductor laser assembly;

[0019] Figure 3 is a schematic cross-sectional view of a downward or bottom emitting semiconductor laser assembly;

[0020] Figure 4 is a schematic cross-sectional view of a portion of a semiconductor laser assembly;

[0021] Figure 5 is a schematic cross-sectional view of a portion of a semiconductor laser assembly;

[0022] Figure 6 is a schematic cross-sectional view of a portion of a semiconductor laser assembly;

[0023] Figure 7 is a schematic cross-sectional view of a portion of a semiconductor laser assembly; and

[0024] Figure 8 is a flow chart of a method for emitting electromagnetic radiation or light. DETAILED DESCRIPTION

[0025] As used herein, spatial or directional terms, such as "left", "right", "inside", "outside", "above", "below", etc., refer to the disclosure as shown in the accompanying drawings. However, it should be understood that the present disclosure can take various alternative orientations, and therefore, these terms should not be considered restrictive. In addition, as used herein, all numbers used in the specification and claims to represent dimensions, physical properties, processing parameters, amounts of ingredients, reaction conditions, etc. should be understood to be modified by the terms "about" or "approximately" in all cases. Therefore, unless otherwise indicated, the numerical values ​​set forth in the following specification and claims can vary according to the desired properties sought to be obtained by the present disclosure. At least, and without attempting to limit the application of the doctrine of equivalents to the scope of the claims, each numerical value should at least be interpreted according to the number of reported significant figures and by applying ordinary rounding techniques. In addition, all ranges disclosed herein should be understood to include starting and ending range values ​​and any and all sub-ranges contained therein. For example, the range "1 to 10" should be considered to include any and all sub-ranges between a minimum of 1 and a maximum of 10 (including the end values); that is, all sub-ranges starting with a minimum of 1 or greater and ending with a maximum of 10 or less, such as 1 to 3.3, 4.7 to 7.5, 5.5 to 10, etc. "A" or "an" means one or more.

[0026] As used herein, "coupled", "coupling" and similar terms refer to two or more elements that are joined, linked, fastened, connected, communicated, or otherwise associated (e.g., mechanically, electrically, fluidically, optically, electromagnetically) with each other. In various examples, the elements may be associated directly or indirectly. As an example, element A may be directly associated with element B. As another example, element A may be indirectly associated with element B, for example, via another element C. It will be understood that it is not necessary to present all the associations between the various elements disclosed herein. Therefore, couplings other than those shown in the figures may also be present.

[0027] As used herein, the phrase "at least one" when used with a list of items means that different combinations of one or more of the listed items may be used, and only one of each item in the list may be required. For example, "at least one of item A, item B, and item C" may include, but is not limited to, item A or item A and item B. This example may also include item A, item B, and item C, or item B and item C. In other examples, "at least one" may be, for example, but not limited to, two of item A, one of item B, and ten of item C; four of item B and seven of item C; and other suitable combinations.

[0028] In one aspect, a semiconductor laser assembly is disclosed herein. The semiconductor laser assembly 100 can be used to emit light in the visible spectrum, such as red, green and / or blue (RGB) light. The disclosed semiconductor laser assembly can include visible light lasers (red, green and blue) for use in various applications, such as medical applications for tissue penetration for diagnosis and treatment. The disclosed content can also be used for projection in screens and displays (including AR / VR displays). In addition, the disclosed can be used for applications requiring white light, such as headlights. An advantage of the disclosed semiconductor laser assembly is that it can be made compact and can be manufactured in high yields.

[0029] Various non-limiting examples will now be described with reference to the drawings, wherein like reference numerals correspond to functionally identical or equivalent elements.

[0030] The present disclosure includes the use of vertical cavity surface emitting laser (VCSEL) or photonic crystal surface emitting laser (PCSEL) technology (e.g., GaAs-based technology) to achieve high reliability and efficiency. In one example, the present disclosure utilizes an integrated RGB light source solution including a polarization-locked VCSEL and a thin film lithium niobate (LiNbO3) optical waveguide 140. The LiNbO3 is polarized by applying a very high bias voltage to temporarily placed electrodes connected to the sides of the waveguide 140. The periodicity of the polarization can be such that when the number of photons generated at a given point in the crystal is maximized, the crystal structure is inverted. After the polarization is completed, the periodically polarized thin film LiNbO3 is transferred and vertically bonded to the top of the VCSEL structure for a top emitting device and to the bottom of the VCSEL structure for a bottom emitting device (see Figure 1-Figure 3 Although the optical waveguide 140 including LiNbO 3 is described herein, the present disclosure may also be applied to an optical waveguide 140 including lithium tantalate (LiTaO 3 ) instead of the optical waveguide 140 including LiNbO 3 .

[0031] The present disclosure uses the nonlinear optical properties of LiNbO3 to convert VCSEL frequency into the visible spectrum. In a non-limiting example ( Figure 4 ), second harmonic generation can be used for frequency doubling of 940nm VCSELs to achieve blue laser emission, for frequency doubling of 1080nm VCSELs to achieve green laser emission, and for frequency doubling of 1260nm VCSELs to achieve red laser emission. In another example, by using the frequency addition generation properties of LiNbO3 and using the frequency addition generation properties of LiNbO3 from 1060nm and 1560nm VCSEL sources (see Figure 5 ) or from 940nm and 1900nm VCSEL sources (see Figure 6) photons, a red laser emission can be obtained. For these configurations, based on frequency addition generation, 3 or 4 laser sources can be used, depending on the exact optical implementation. The configuration of the lasers (single line / array) can be selected based on the power requirements of the intended application. Pick and place tools can be used to combine subsystems of different colors in a full RGB solution within the present disclosure.

[0032] To provide maximum frequency conversion efficiency, the VCSEL light can be polarized in the direction of the LiNbO3 thickness. This can be achieved by implementing a polarization grating on top of or inside the cavity of the VCSEL structure.

[0033] Through the coordinated design of the VCSEL structure and the LiNbO3 thin film (i.e., phase, field matching optimization, beam shaping / focusing), high power conversion efficiency and high beam quality of the VCSEL can be maintained in the disclosed assembly.

[0034] refer to Figure 1 In one non-limiting example, the top emitting semiconductor laser assembly 100 includes an array of surface emitting lasers 110 having a light emitting surface 112 and an opposing surface 114. The array of surface emitting lasers 110 may include any type of laser required for the intended application. In one example, the array of surface emitting lasers 110 includes a plurality of VCELs. In another example, the array of surface emitting lasers 110 includes a plurality of PCSELs.

[0035] Figure 1 The top emitting semiconductor laser assembly 100 shown includes a first or bottom side contact layer 120 on or above the opposing surface 114 and a second or top side contact layer 130 on or above the light emitting surface 112. The first and second contact layers 120 and 130 can be configured in a manner known in the art to enable power from an external power source to the emitters 116 ( Figure 4-Figure 7 ) to apply an electrical bias so that the array of surface emitting lasers 110 also outputs or emits laser light 170 in an upward direction in a manner known in the art. Each of the first and second contact layers 120 and 130 can have any suitable and / or desired thickness for the desired current density of the application and can be composed of any suitable and / or desired conductive material or compound, such as, but not limited to, gold-germanium (AuGe) for an n-type contact or titanium-platinum-gold (TiPtAu) for a p-type contact.

[0036] refer to Figure 2 and Figure 3 , Figure 2 and Figure 3The example bottom emitting semiconductor laser component 100 shown in FIG. 1 may include a pair of spaced apart second or top side contact layers 130 on or above an opposing surface 114 , which is a top surface of the bottom emitting semiconductor laser component 100 in these figures. Figure 2 and Figure 3 The bottom emitting semiconductor laser components 100 shown in FIG. 1 do not include any components on their bottom surfaces that are similar to those of FIG. Figure 1 A first contact layer 120 similar to that shown in FIG. 1 is provided to prevent such a contact layer from interfering with the laser light 170 emitted via the bottom surface in a manner known in the art.

[0037] Figure 2 and Figure 3 A pair of second or top side contact layers 130 on the opposite or top surface 114 of the bottom emitting semiconductor laser assembly 100 as shown may be configured in a manner known in the art to enable electrical bias to be applied from an external power source to the bottom emitting semiconductor laser assembly 100. Figure 2 and Figure 3 The emitter 116 of the array of surface emitting lasers 110 ( Figure 4-Figure 7 ), so that the array of surface emitting lasers 110 also outputs or emits laser light 170 in a downward direction in a manner known in the art. Figure 2 and Figure 3 Each contact layer 130 in can have any suitable and / or desired thickness for the desired current density of the application and can be composed of any suitable and / or desired conductive material or compound, such as but not limited to: gold-germanium (AuGe) for n-type contacts or titanium-platinum-gold (TiPtAu) for p-type contacts.

[0038] like Figure 1-Figure 7 As shown, the semiconductor laser assembly 100 also includes an optical waveguide 140 coupled to the light emission direction side of the light emitting surface 112. In one example, the optical waveguide 140 includes lithium. In a non-limiting example, the optical waveguide 140 includes lithium niobate, which provides the desired nonlinear optical properties that enable frequency doubling. It should be understood that other materials or compounds with nonlinear optical properties comparable to those of lithium niobate can be achieved. For example, the optical waveguide can include lithium tantalate or other lithium or non-lithium materials or compounds with comparable optical properties. In one example, the optical waveguide 140 is a thin film lithium niobate waveguide.

[0039] like Figure 1-Figure 3 As shown, the optical waveguide 140 of the semiconductor laser assembly 100 can be periodically polarized multiple times. In one example, the optical waveguide 140 can be periodically polarized at 180° or at approximately 180°. Figure 1-Figure 3In the example shown, the optical waveguide 140 can be periodically polarized eight times or eight periods at polarization angles of 0° and 180° (or 180° and 0°). However, this should not be construed as limiting, as the number of times or periods that the optical waveguide 140 can be periodically polarized and the polarization angle can be selected by a person skilled in the art for a particular application. The use of the periodically poled lithium niobate thin film optical waveguide 140 provides an effective medium for nonlinear wavelength conversion processes, such as frequency doubling. The semiconductor laser assembly 100 can include a coating 124, such as an anti-reflection coating, on the surface of the optical waveguide 140 opposite to the array of surface emitting lasers 110.

[0040] refer to Figure 4-Figure 7 , the array of surface emitting lasers 110 of the semiconductor laser assembly 100 may include a plurality of emitters 116 configured to emit electromagnetic radiation or light of various wavelengths. In some non-limiting examples, the array of surface emitting lasers 110 may include at least one emitter 116a configured to emit electromagnetic radiation or light of a wavelength between 1200nm and 1300nm. In another example, the array of surface emitting lasers 110 may include at least one emitter 116b configured to emit electromagnetic radiation or light of a wavelength between 1000nm and 1100nm. In another example, the array of surface emitting lasers 110 may include at least one emitter 116c configured to emit electromagnetic radiation or light of a wavelength between 900nm and 1000nm. In another example, the array of surface emitting lasers 110 may include at least one emitter 116d configured to emit electromagnetic radiation or light of a wavelength between 1000nm and 1100nm. In another example, the array of surface emitting lasers 110 may include at least one emitter 116E configured to emit electromagnetic radiation or light at a wavelength between 1500 nm and 1600 nm. In yet another example, the array of surface emitting lasers 110 may include at least one emitter 116F configured to emit electromagnetic radiation or light at a wavelength between 1850 nm and 1950 nm.

[0041] refer to Figure 7 , the disclosed semiconductor laser assembly 100 may include multiple emitters 116 having different polarizations. Figure 7In the example of , the array of surface emitting lasers 110 includes four emitters 116. Some of the emitters 116b in the array may have polarizations aligned with the width of the thin film optical waveguide 140. The light from these emitters will cause frequency doubling at the output of the thin film optical waveguide 140. Other emitters 116a in the array may have polarizations aligned perpendicular to the width of the thin film optical waveguide 140. The light from the emitter 116a will not be affected by nonlinear effects in the thin film optical waveguide 140, and the output wavelength will remain the same as the input wavelength (e.g., IR). The polarization locking of the emitter can be defined by the photonic crystal design for a PCSEL arrangement or by the grating orientation for a VCSEL arrangement. Thus, as Figure 7 As shown in the example of , the array of surface emitting lasers 110 may include at least one emitter 116a having a polarization aligned with the width of the optical waveguide 140 and / or at least one emitter 116b having a polarization perpendicular to the width of the optical waveguide 140.

[0042] Return to reference Figure 1 In an example, the semiconductor laser assembly 100 may include one or more of dielectric layers 150 and 151. In an example, the dielectric layer 151 may be located between the array of surface emitting lasers 110 and the optical waveguide 140. In an example, the dielectric layer 151 may include a refractive index matching dielectric. In an example, the refractive index matching dielectric including the dielectric layer 151 may have a refractive index of the refractive index n1 of the array of surface emitting lasers 110 multiplied by the square of the refractive index n2 of the optical waveguide 140, that is, (n1 x n2) 2 The dielectric layer 150 on the remainder of the surface 112 surrounding the optical waveguide 140 may be a passivation layer, such as silicon nitride, which may prevent moisture and / or other undesirable contaminants from contacting the remainder of the surface 112 .

[0043] refer to Figure 2 In an example, the semiconductor laser assembly 100 may include a semi-insulating substrate 160 located between the surface emitting laser 110 and the optical waveguide 140. The semi-insulating substrate 160 may include any material having the necessary insulating material properties. In one example, the semi-insulating substrate 160 may include gallium arsenide (GaAs).

[0044] refer to Figure 5 In an example, the semiconductor laser assembly 100 may include a beam combiner 180 located between the array of surface emitting lasers 110 and the optical waveguide 140. In an example, the beam combiner 180 may be located Figure 5In one example, the beam combiner 180 provides the electromagnetic radiation or light output by the emitters 116D and 116E, whose wavelengths are, for example, 1060 nm (corresponding to a frequency f1 of about 943 KHz) and 1560 nm (corresponding to a frequency f2 of about 641 kHz), respectively, to the optical waveguide 140 located on top of the beam combiner 180. In this example, the optical waveguide 140 adds these frequencies f1 and f2 to obtain output electromagnetic radiation or light having a wavelength of about 630 nm corresponding to the color red (corresponding to a frequency f3 of about 1590 kHz). Figure 5 In the illustrated example semiconductor laser assembly 100, the emitter 116C is directly located under the optical waveguide 140 without an intermediate beam combiner 180 therebetween, and the emitter 116b is directly located under the optical waveguide 140 without an intermediate beam combiner 180 therebetween. In the present disclosure, because the values ​​of frequency and wavelength are rounded to three or four digits, any digits thereafter are omitted, the value of each frequency and / or wavelength may be referred to as, but not limited to, "about" a certain value. However, this should not be construed as limiting.

[0045] refer to Figure 8 , also disclosed is a method 200 for emitting electromagnetic radiation or light 170, such as Figure 4-Figure 7 As shown. The method 200 may be used with a VCSEL or PCSEL assembly. In one example, the method 200 may include coupling 220 the lithium niobate optical waveguide 140 to the array of surface emitting lasers 110. In one example, coupling 220 may include Figure 3 Directly or as shown Figure 2 The optical waveguide 140 is shown bonded to the array of surface emitting lasers 110 via a semi-insulating substrate 160. In another example, the coupling 220 may include regrowing the optical waveguide 140 to the surface of the surface emitting laser 110.

[0046] In one example, the method 200 may include coupling 220 to produce a semiconductor laser assembly 100 having an array of surface emitting lasers 110 having a light emitting surface 112 and an opposing surface 114. The array of surface emitting lasers 110 may include any type or wavelength of lasers required for the intended application. In one example, the array of surface emitting lasers 110 may include a plurality of vertical cavity surface emitting lasers (VCELs). In another example, the array of surface emitting lasers 100 may include a plurality of photonic crystal surface emitting lasers (PCSELs).

[0047] In an example, the method 200 forms Figure 1The semiconductor laser assembly 100 shown may include a first or bottom-side contact layer 120 on or above the opposing (bottom) surface 114 and a second or top-side contact layer 130 on a portion or part of or above the light emitting surface 112. Each contact layer 120 and 130 may have any suitable and / or desired thickness for the desired current density of the application and may be composed of any suitable and / or desired conductive material or compound, such as, but not limited to, gold-germanium (AuGe) for an n-type contact or titanium-platinum-gold (Ti-Pt-Au) for a p-type contact.

[0048] In another example, the method 200 forms Figure 2 and Figure 3 The semiconductor laser assembly 100 shown may include a pair of spaced apart contact layers 130 on or above portions or parts of the opposing (top) surface 114, and no contacts on the bottom surface. Each contact layer 130 may have any suitable and / or desired thickness for the desired current density of the application, and may be composed of any suitable and / or desired conductive material or compound, such as, but not limited to, gold-germanium (Au-Ge) for n-type contacts or titanium-platinum-gold (Ti-Pt-Au) for p-type contacts.

[0049] like Figure 1-Figure 7 As shown, the semiconductor laser component 100 formed by the method 200 may include an upwardly facing light emitting surface 112 ( Figure 1 on or above the light emitting surface 112 ( Figure 2 and 3 The optical waveguide 140 above or below the surface emitting laser 110 is configured to receive electromagnetic radiation or light emitted from the array of surface emitting lasers 110. For example, due to Figure 1 A top emitting semiconductor laser assembly 100 is shown, so the optical waveguide 140 is positioned on top of the light emitting surface 112 that emits electromagnetic radiation or light upward in the figure. Figure 2 and Figure 3 A bottom emitting semiconductor laser assembly 100 is shown so that the optical waveguide 140 is located above or below the light emitting surface 112 that emits electromagnetic radiation or light downward in the figure. Herein, the terms "electromagnetic radiation," "light," and "laser" may be used interchangeably when referring to the emission of electromagnetic radiation, light, or laser light from any surface emitting laser or array of surface emitting lasers 110.

[0050] In one example, the optical waveguide 140 includes lithium. In one non-limiting example, the optical waveguide 140 may include lithium niobate, which provides desirable nonlinear optical properties that enable frequency doubling of a single wavelength of electromagnetic radiation or light (of frequency f1) propagating through the optical waveguide 140, or when the optical waveguide 140 is used with a beam combiner 180, the beam combiner 180 provides two different wavelengths of electromagnetic radiation or light (of frequencies f1 and f2) to the optical waveguide 140, and the optical waveguide 140 emits electromagnetic radiation or light of frequency f3, which is the sum of frequencies f1 and f2, i.e., f3=f1+f2. It should be understood that other materials having comparable nonlinear optical properties to lithium niobate may be implemented. For example, the optical waveguide 140 may include lithium tantalate or other lithium or non-lithium materials having comparable optical properties. In one example, the optical waveguide 140 is a thin film lithium niobate waveguide.

[0051] like Figure 1-Figure 3 As shown, the optical waveguide 140 of the semiconductor laser component 100 formed by the method 200 can be periodically polarized. In one example, the optical waveguide 140 is periodically polarized at about 180°. The use of the periodically poled lithium niobate thin film optical waveguide 140 provides an effective medium for a nonlinear wavelength conversion process, such as for doubling the frequency of a single wavelength of electromagnetic radiation or light input into the optical waveguide 140, or for adding the frequencies of at least two wavelengths of electromagnetic radiation or light input into the optical waveguide 140, such as from the beam combiner 110. The semiconductor laser component 100 may include a coating 124, such as an anti-reflection coating, on a surface of the optical waveguide 140 opposite to the array of surface emitting lasers 110.

[0052] refer to Figure 4-Figure 7, the semiconductor laser assembly 100 formed by the method 200 may include an array of surface emitting lasers 110, which includes a plurality of emitters 116 configured to emit electromagnetic radiation or light of various wavelengths. In one example, the array of surface emitting lasers 110 may include at least one emitter 116a, which is configured to emit electromagnetic radiation or light of a wavelength between 1200nm and 1300nm. In another example, the array of surface emitting lasers 110 may include at least one emitter 116b, which is configured to emit electromagnetic radiation or light of a wavelength between 1000nm and 1100nm. In another example, the array of surface emitting lasers 110 may include at least one emitter 116c, which is configured to emit electromagnetic radiation or light of a wavelength between 900nm and 1000nm. In another example, the array of surface emitting lasers 110 may include at least one emitter 116d, which is configured to emit electromagnetic radiation or light of a wavelength between 1000nm and 1100nm. In another example, the array of surface emitting lasers 110 may include at least one emitter 116E configured to emit electromagnetic radiation or light at a wavelength between 1500 nm and 1600 nm. In yet another example, the array of surface emitting lasers 110 may include at least one emitter 116F configured to emit electromagnetic radiation or light at a wavelength between 1850 nm and 1950 nm.

[0053] Figure 4-Figure 7 The array of surface emitting lasers 110 is shown as when, for example, Figure 1 The semiconductor laser assembly 100 shown emits electromagnetic radiation or laser light 170 in an upward direction when used together. However, it should be understood that Figure 4-Figure 7 The array of surface emitting lasers 110 in any of the above may be inverted (ie, the thin film optical waveguide 140 is below the emitter 116), and thus the array of surface emitting lasers 110 may be reversed when, for example, Figure 2 and 3 The semiconductor laser assembly 100 is shown emitting electromagnetic radiation or laser light 170 in a downward direction when used together.

[0054] refer to Figure 7 , the disclosed semiconductor laser assembly 100 formed by the method 200 may include a plurality of emitters 116 having different polarizations. Figure 7 In the example of FIG. 1 , the array of surface emitting lasers 110 may include four emitters 116. Some of the emitters 116b in the array may have a width (in the range of 100 to 1000) that is equal to the width of the thin film optical waveguide 140. Figure 7The light from these emitters 116b will result in a doubled frequency at the output of the thin film light guide 140. Other emitters 116a in the array may have a width perpendicular to the thin film light guide 140 (e.g., Figure 7 The light from these emitters 116a will not be affected by the nonlinear effects of the thin film optical waveguide 140 and the wavelength will remain the same as the input wavelength (e.g., IR). The polarization locking of each emitter can be defined by the photonic crystal design for PCSEL arrangements or by the grating orientation for VCSEL arrangements. Figure 7 As shown in the example of , the array of surface emitting lasers 110 may include at least one emitter 116a having a polarization aligned with the width of the optical waveguide 140 and / or at least one emitter 116b having a polarization perpendicular to the width of the optical waveguide 140.

[0055] refer to Figure 2 In one or more examples, the semiconductor laser component 100 formed by the method 200 may include a semi-insulating substrate 160 located between the surface emitting laser 110 and the optical waveguide 140. The semi-insulating substrate 160 may include any material having the necessary insulating material properties. In one example, the semi-insulating substrate 160 may include gallium arsenide (GaAs).

[0056] refer to Figure 5 and Figure 6 In one or more examples, the semiconductor laser assembly 100 formed by the method 200 can include a beam combiner 180 positioned between two or more emitters 116 of the array of surface emitting lasers 110 and the single optical waveguide 140 . Figure 6 The beam combiner 180 can directly pass the electromagnetic radiation or light (frequency f1) output by the emitter 116C to the optical waveguide 140 located on top of or above the emitter 116C. In the above manner, the optical waveguide 140 located on top of or above the emitter 116C doubles the frequency of the electromagnetic radiation or light directly output by the emitter 116C to the optical waveguide 140. In addition, Figure 6The beam combiner 180 may pass or direct the electromagnetic radiation or light (frequency f1) output by the emitter 116C to the optical waveguide 140 positioned on top of or above the emitter 116F. The optical waveguide 140 positioned on top of or above the emitter 116F also receives the electromagnetic radiation or light (frequency f2) output by the emitter 116F. In the manner described above, the optical waveguide 140 positioned on top of or above the emitter 116F adds the frequencies (f1 and f2) of the electromagnetic radiation or light received by the optical waveguide 140 from the emitters 116C and 116F, and outputs or emits electromagnetic radiation or light 170 of frequency f3, which is the sum of the frequencies f1 and f2, i.e., f3=f1+f2.

[0057] Return to reference Figure 8 , the method 200 may include emitting 230 electromagnetic radiation or light at a first wavelength from the semiconductor laser component 100 to the optical waveguide 140. Then, the electromagnetic radiation or light at the first wavelength is subsequently emitted from the optical waveguide 140 at a second wavelength. In one example, the second wavelength may be shorter than the first wavelength. For example, the output frequency of the second wavelength may be doubled so that the output wavelength is approximately half the input wavelength. In one example, the second wavelength is approximately half the first wavelength.

[0058] The emitting 230 of the method 200 may include emitting electromagnetic radiation or light in the RGB visible spectrum. Thus, in one example, the emitting 230 may include emitting electromagnetic radiation or light having a wavelength between 1200 nm and 1300 nm from the emitter 116 of the semiconductor laser component 100 toward the optical waveguide 140 such that the frequency is substantially doubled when passing through the optical waveguide 140.

[0059] The transmitting 230 of the method 200 may also include combining (adding) electromagnetic radiation or light emitted at two or more different average wavelengths to produce different output wavelengths. For example, the transmitting 230 may include transmitting electromagnetic radiation or light at a first wavelength (corresponding to a first frequency f1), such as a wavelength between 1000 nm and 1100 nm, from the first emitter 116D to the beam combiner 180, and simultaneously transmitting electromagnetic radiation or light at a second wavelength (corresponding to a second frequency f2), such as a wavelength between 1500 nm and 1600 nm, from the second emitter 116E to the beam combiner 180. The beam combiner 180 routes the electromagnetic radiation or light at the first and second wavelengths (and, therefore, the first and second frequencies f1 and f2) to the optical waveguide 140 coupled to the beam combiner 180, which outputs or transmits electromagnetic radiation or light 170 at a frequency f3, which is the sum of the frequencies f1 and f2, i.e., f3=f1+f2. In the above examples, the first and second wavelengths and the first and second frequencies f1 and f2 are different, and the frequency f3, and therefore the wavelength of the output electromagnetic radiation or light 170, is different from the first and second frequencies f1 and f2 and the first and second wavelengths. It should be understood that the above examples of wavelengths and frequencies are merely exemplary, and any two or more average wavelengths input to the beam combiner 180 may be routed to and summed by the optical waveguide 140 coupled to the beam combiner 180.

[0060] In one or more examples, method 200 can include poling 210 the lithium niobate thin film to produce a periodically poled optical waveguide having 180° periodic inversion domains. In one example, poling 210 includes coupling a plurality of electrodes to the lithium niobate film and applying one or more appropriate electrical biases to the electrodes to produce the periodically poled optical waveguide 140.

[0061] Other non-limiting examples or aspects of the present disclosure are set forth in the following illustrative and exemplary numbered clauses:

[0062] Item 1. A semiconductor laser assembly comprising: an array of surface emitting lasers having a light emitting surface and an opposing surface; at least one electrical contact electrically connected to provide an electrical bias from an external power source to the array of surface emitting lasers; and an optical waveguide above the light emitting surface, wherein the optical waveguide comprises lithium.

[0063] Clause 2. The semiconductor laser assembly of Clause 1, wherein the at least one electrical contact may include: one contact on the light emitting surface and another contact on an opposing surface, or a pair of contacts on opposing surfaces.

[0064] Clause 3. A semiconductor laser component according to clause 1 or 2, wherein the optical waveguide may comprise lithium niobate.

[0065] Clause 4. The semiconductor laser component of any of Clauses 1-3, wherein the optical waveguide may comprise lithium tantalate.

[0066] Item 5. A semiconductor laser component according to any one of items 1 to 4, wherein the optical waveguide can be periodically polarized by 180°.

[0067] Clause 6. The semiconductor laser assembly of any of Clauses 1-5, wherein the array of surface emitting lasers may include a plurality of vertical cavity surface emitting lasers or a plurality of photonic crystal surface emitting lasers.

[0068] Clause 7. The semiconductor laser assembly of any of Clauses 1-6, wherein the array of surface emitting lasers comprises top emitting lasers or bottom emitting lasers.

[0069] Clause 8. The semiconductor laser assembly of any of Clauses 1-7, wherein the array of surface emitting lasers comprises at least one emitter configured to emit electromagnetic radiation at a wavelength between 1850 nm and 1950 nm.

[0070] Clause 9. The semiconductor laser assembly of any of Clauses 1-8, wherein the array of surface emitting lasers comprises at least one emitter configured to emit electromagnetic radiation at a wavelength between 1200 nm and 1300 nm.

[0071] Clause 10. The semiconductor laser assembly of any of Clauses 1-9, wherein the array of surface emitting lasers comprises at least one emitter configured to emit electromagnetic radiation at a wavelength between 1000 nm and 1100 nm.

[0072] Clause 11. The semiconductor laser assembly of any of Clauses 1-10, wherein the array of surface emitting lasers comprises at least one emitter configured to emit electromagnetic radiation at a wavelength between 900 nm and 1000 nm.

[0073] Clause 12. The semiconductor laser assembly of any of Clauses 1-11, wherein the array of surface emitting lasers comprises at least one emitter configured to emit electromagnetic radiation at a wavelength between 1500 nm and 1600 nm.

[0074] Clause 13. The semiconductor laser assembly of any of Clauses 1-12, wherein the array of surface emitting lasers comprises at least one emitter having a polarization aligned with a width of the optical waveguide.

[0075] Clause 14. The semiconductor laser assembly of any of Clauses 1-13, wherein the array of surface emitting lasers comprises at least one emitter having a polarization perpendicular to the width of the optical waveguide.

[0076] Clause 15. The semiconductor laser assembly of any of Clauses 1-14, further comprising a semi-insulating substrate positioned between the surface emitting laser and the optical waveguide.

[0077] Clause 16. The semiconductor laser component of any one of Clauses 1-15, wherein the semi-insulating substrate comprises gallium arsenide GaAs.

[0078] Clause 17. The semiconductor laser assembly of any of Clauses 1-16, further comprising a beam combiner positioned between the array of surface emitting lasers and the optical waveguide.

[0079] Clause 18. The semiconductor laser component according to any one of Clauses 1-17, further comprising an anti-reflection coating on the optical waveguide.

[0080] Item 19. A method for emitting electromagnetic radiation, the method comprising: coupling an optical waveguide comprising lithium with a semiconductor laser; and emitting electromagnetic radiation of a first wavelength from the semiconductor laser to the optical waveguide, wherein electromagnetic radiation of a second wavelength is emitted from the optical waveguide, and wherein the second wavelength is shorter than the first wavelength.

[0081] Clause 20. The method of Clause 19, wherein the second wavelength is approximately half the first wavelength.

[0082] Clause 21. The method according to clause 19 or 20, characterized in that the coupling comprises bonding or regrowth.

[0083] Clause 22. The method of any of clauses 19-21, wherein the emitting comprises emitting electromagnetic radiation having a wavelength between 1200 nm and 1300 nm from the semiconductor laser to the optical waveguide, whereby the frequency is doubled or substantially doubled when passing through the optical waveguide.

[0084] Clause 23. A method according to any one of clauses 19-22, wherein the emission comprises: emitting electromagnetic radiation of a first wavelength from a first emitter of a semiconductor laser to a beam combiner; emitting electromagnetic radiation of a second wavelength from a second emitter of the semiconductor laser to the beam combiner; and emitting electromagnetic radiation of the first wavelength and the second wavelength from the beam combiner to an optical waveguide, wherein the optical waveguide adds the first wavelength and the second wavelength when passing through the optical waveguide.

[0085] Clause 24. A method according to any of clauses 19-23, wherein: the first wavelength is between 900 nm and 1000 nm; and the second wavelength is between one of: (1) 900 nm and 1000 nm, or (2) 1850 nm and 1950 nm.

[0086] Clause 25. The method of any of Clauses 19-24, further comprising poling the lithium niobate or lithium tantalate thin film to produce a periodically poled optical waveguide having 180° periodic inversion domains.

[0087] Although various examples of the disclosed semiconductor laser assembly have been shown and described, modifications may occur to those skilled in the art upon reading the specification. The present application includes such modifications and is limited only by the scope of the claims.

Claims

1. A semiconductor laser assembly, comprising: an array of surface emitting lasers having a light emitting surface and an opposing surface; at least one electrical contact electrically connected to provide an electrical bias from an external power source to the array of surface emitting lasers; as well as An optical waveguide is over the light emitting surface, wherein the optical waveguide comprises lithium.

2. The semiconductor laser assembly of claim 1 , wherein the at least one electrical contact comprises: One contact on the light emitting surface and another contact on the opposite surface, or A pair of contacts on opposing surfaces.

3. The semiconductor laser assembly of claim 1, wherein the optical waveguide comprises lithium niobate.

4. The semiconductor laser assembly of claim 1, wherein the optical waveguide comprises lithium tantalate.

5. The semiconductor laser assembly according to claim 1, wherein the optical waveguide is periodically polarized by 180°.

6. The semiconductor laser assembly of claim 1, wherein the array of surface emitting lasers comprises a plurality of vertical cavity surface emitting lasers or a plurality of photonic crystal surface emitting lasers.

7. The semiconductor laser assembly of claim 1, wherein the array of surface emitting lasers comprises top emitting lasers or bottom emitting lasers.

8. The semiconductor laser assembly of claim 1, wherein the array of surface emitting lasers comprises at least one emitter configured to emit electromagnetic radiation at a wavelength between 1850 nm and 1950 nm.

9. The semiconductor laser assembly of claim 1, wherein the array of surface emitting lasers comprises at least one emitter configured to emit electromagnetic radiation at a wavelength between 1200 nm and 1300 nm.

10. The semiconductor laser assembly of claim 1, wherein the array of surface emitting lasers comprises at least one emitter configured to emit electromagnetic radiation at a wavelength between 1000 nm and 1100 nm.

11. The semiconductor laser assembly of claim 1, wherein the array of surface emitting lasers comprises at least one emitter configured to emit electromagnetic radiation at a wavelength between 900 nm and 1000 nm.

12. The semiconductor laser assembly of claim 1, wherein the array of surface emitting lasers comprises at least one emitter configured to emit electromagnetic radiation at a wavelength between 1500 nm and 1600 nm.

13. The semiconductor laser assembly of claim 1, wherein the array of surface emitting lasers comprises at least one emitter having a polarization aligned with a width of the optical waveguide.

14. The semiconductor laser assembly of claim 1, wherein the array of surface emitting lasers comprises at least one emitter having a polarization perpendicular to a width of the optical waveguide.

15. The semiconductor laser assembly of claim 1 further comprising a semi-insulating substrate positioned between the surface emitting laser and the optical waveguide.

16. The semiconductor laser assembly of claim 15, wherein the semi-insulating substrate comprises gallium arsenide (GaAs).

17. The semiconductor laser assembly of claim 1 further comprising a beam combiner positioned between the array of surface emitting lasers and the optical waveguide.

18. The semiconductor laser assembly of claim 1 further comprising an anti-reflection coating on the optical waveguide.

19. A method for emitting electromagnetic radiation, the method comprising: coupling an optical waveguide including lithium to a semiconductor laser; as well as Electromagnetic radiation of a first wavelength is emitted from the semiconductor laser to the optical waveguide, wherein electromagnetic radiation of a second wavelength is emitted from the optical waveguide, and wherein the second wavelength is shorter than the first wavelength.

20. The method of claim 19, wherein the second wavelength is approximately half the first wavelength.

21. The method of claim 19, wherein the coupling comprises bonding or regrowth.

22. The method of claim 19, wherein the emitting comprises emitting electromagnetic radiation having a wavelength between 1200 nm and 1300 nm from the semiconductor laser into the optical waveguide, whereby the frequency is doubled or substantially doubled when passing through the optical waveguide.

23. The method of claim 19, wherein the transmitting comprises: emitting electromagnetic radiation of a first wavelength from a first emitter of a semiconductor laser toward a beam combiner; emitting electromagnetic radiation of a second wavelength from a second emitter of the semiconductor laser toward the beam combiner; as well as Electromagnetic radiation of a first wavelength and a second wavelength is emitted from the beam combiner to the optical waveguide, which adds the first wavelength and the second wavelength while passing through the optical waveguide.

24. The method of claim 23, wherein: The first wavelength is between 900 nm and 1000 nm; and The second wavelength is between one of: (1) 900 nm and 1000 nm, or (2) 1850 nm and 1950 nm.

25. The method of claim 19, further comprising poling the lithium niobate or lithium tantalate thin film to produce a periodically poled optical waveguide having 180° periodic inversion domains.

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