SEMICONDUCTOR LASER COMPONENT AND METHOD FOR OPERATING AT LEAST ONE SEMICONDUCTOR LASER

Abstract

Semiconductor laser component (1) comprising a plurality of semiconductor lasers (10) and a beam combiner (20) which is designed to combine radiation emitted by the semiconductor lasers (10), wherein - the semiconductor lasers (10) each emit a primary electromagnetic radiation of a primary spectral bandwidth in the visible wavelength range, - the primary electromagnetic radiation of the semiconductor lasers (10) is coupled into the beam combiner (20), - secondary electromagnetic radiation is coupled out of the beam combiner (20), which is formed from a superposition of the primary electromagnetic radiation of the semiconductor lasers (10), and - the secondary electromagnetic radiation has a secondary spectral bandwidth that is at least twice the average of the primary spectral bandwidths, and - an optical layer sequence (70) is arranged within a resonator (100) of at least one semiconductor laser (10) at a coupling-out region (60), which optical layer sequence (70) is formed with a material having a perovskite structure and whose refractive index can be changed by applying an external electrical voltage or an electrical current.

Description

[0001] An optoelectronic semiconductor laser component and a method for operating at least one semiconductor laser are specified.

[0002] The optoelectronic semiconductor laser component is designed in particular to generate electromagnetic radiation, for example light perceptible to the human eye.

[0003] From the documents US 2019 / 0 361 327 A1, JP 2012 59 963 A, US 2013 / 0 194 787 A1, DE 10 2009 013 909 A1, EP 2 048 753 A1, US 2002 / 0 196 414 A1, US 8 451 876 B1, US 2016 / 0 372 893 A1, US 2003 / 0 026 311 A1, US 2014 / 0 029 638 A1 and US 5 228 050 A an optoelectronic semiconductor laser component and a method for operating at least one semiconductor laser are known.

[0004] One problem to be solved is to provide an optoelectronic semiconductor laser component that emits electromagnetic radiation with an increased spectral bandwidth.

[0005] The semiconductor laser component comprises a plurality of semiconductor lasers. Each semiconductor laser is designed to emit coherent or at least partially coherent electromagnetic radiation. Each semiconductor laser preferably comprises a p-conducting semiconductor region and an n-conducting semiconductor region, as well as an active region designed to emit electromagnetic radiation.

[0006] In particular, the electromagnetic radiation emitted by semiconductor lasers has essentially the same main emission wavelength. In case of doubt, the main emission wavelength of an electromagnetic emission spectrum is the wavelength at which the spectrum exhibits a global intensity maximum.

[0007] The semiconductor laser component comprises a beam combiner configured to combine the electromagnetic radiation of the semiconductor lasers. Preferably, the electromagnetic radiation of all semiconductor lasers is superimposed. The beam combiner has, for example, a plurality of coupling surfaces for coupling electromagnetic radiation into the beam combiner, a plurality of waveguides for guiding the coupled electromagnetic radiation and superimposing them, and an output coupling surface for outputting the electromagnetic radiation.

[0008] The semiconductor lasers each emit primary electromagnetic radiation with a primary spectral bandwidth in the visible wavelength range. The spectral range visible to humans extends, in particular, from 380 nm to 780 nm. The spectral bandwidth here and below is understood to be a "full width at half maximum" (FWHM) bandwidth. For example, each semiconductor laser emits primary electromagnetic radiation with a different main emission wavelength. The main emission wavelengths of the semiconductor lasers preferably differ by 0.5 nm to 3 nm, and in particular by 1 nm to 2 nm.

[0009] The primary electromagnetic radiation from the semiconductor laser is coupled into the beam combiner. Coupling into the beam combiner occurs primarily via a coupling surface of the beam combiner.

[0010] Secondary electromagnetic radiation, formed by a superposition of the primary electromagnetic radiation from the semiconductor lasers, is coupled out of the beam combiner. Preferably, secondary radiation is coupled out of the combiner, formed by a superposition of the primary radiation from all semiconductor lasers. For example, the secondary electromagnetic radiation is coupled out at an output surface of the beam combiner.

[0011] The secondary electromagnetic radiation has a secondary spectral bandwidth that is at least twice the average of the primary spectral bandwidths. The average here and in the following is understood to be an arithmetic mean of the bandwidths. An increased spectral bandwidth leads to a beneficially reduced coherence length.

[0012] The semiconductor laser component comprises a plurality of semiconductor lasers and a beam combiner configured to combine radiation emitted by the semiconductor lasers, wherein - the semiconductor lasers each emit a primary electromagnetic radiation of a primary spectral bandwidth in the visible wavelength range, - the primary electromagnetic radiation of the semiconductor lasers is coupled into the beam combiner, - a secondary electromagnetic radiation is coupled out of the beam combiner, which is formed from a superposition of the primary electromagnetic radiation of the semiconductor lasers, and - the secondary electromagnetic radiation has a secondary spectral bandwidth that is at least twice the average of the primary spectral bandwidths.

[0013] A semiconductor laser component described here is based on the following considerations, among others: Laser components exhibit good beam quality, making them particularly suitable for use in display units or projection devices. In addition to good beam quality, laser components also have a particularly small emission area, which approximately corresponds to a point light source. This results in an advantageously high luminance, which can contribute to the miniaturization of optical systems. However, when using a laser component in a visible wavelength range, unwanted interference effects, for example in the form of speckles, are sometimes perceptible to an observer. These interference effects lead to uneven illumination and disturbing patterns.Furthermore, the use of diffractive optics together with electromagnetic radiation with a large coherence length is complicated by further undesirable interference effects.

[0014] The semiconductor laser component described here utilizes, among other things, the idea of ​​generating electromagnetic radiation with an increased spectral bandwidth and consequently with a reduced coherence length, which nevertheless exhibits sufficiently good beam quality. For this purpose, secondary electromagnetic radiation with an increased secondary spectral bandwidth can be generated by superimposing a plurality of primary electromagnetic radiations from a plurality of semiconductor lasers. Increasing the spectral bandwidth is accompanied by a reduction in the coherence length. Less coherent radiation advantageously reduces the intensity of any unwanted interference effects that occur. This advantageously facilitates the use of diffractive optics and advantageously reduces or eliminates the occurrence of speckles.

[0015] According to at least one embodiment of the semiconductor laser component, the secondary spectral bandwidth is between 5 nm and 10 nm. A larger spectral bandwidth advantageously reduces or avoids the disruptive influence of optical interference effects.

[0016] According to at least one embodiment of the semiconductor laser component, the beam combiner is a monolithic component. A monolithic component is characterized in particular by its integral design. Thus, the beam combiner is particularly easy to adjust relative to a plurality of semiconductor lasers or a subsequent optical element. Furthermore, a monolithic optical component advantageously achieves high optical efficiency by avoiding refractive index jumps at material boundaries.

[0017] According to at least one embodiment of the semiconductor laser component, the semiconductor lasers have different resonator lengths. A resonator comprises at least two reflective surfaces, between which an optically active medium is arranged. In an optical resonator, electromagnetic radiation whose wavelength satisfies a resonance condition of the resonator is primarily amplified. The resonance wavelength of the resonator is determined, among other things, by the length of the resonator. A different resonator length of a semiconductor laser therefore results in a different main emission wavelength of the associated semiconductor laser. This advantageously allows for an increased secondary spectral bandwidth to be achieved.Preferably, the resonator length of a semiconductor laser component differs from at least one further semiconductor laser component, in particular the semiconductor laser component whose resonator length is closest to the resonator length of the first-mentioned semiconductor laser component, by at least 5% and by at most 100%, particularly preferably by at most 20%.

[0018] According to at least one embodiment of the semiconductor laser component, the semiconductor lasers are arranged on a common substrate. Preferably, all semiconductor lasers are arranged on a common substrate. Arranging the semiconductor lasers on a common substrate facilitates alignment of the individual emitters, for example, relative to a beam combiner. A common substrate can further simplify electrical contacting of the semiconductor lasers by acting as a common anode or cathode. Particularly good cooling of the semiconductor lasers is achieved when a p-conducting semiconductor layer of each semiconductor laser is mounted facing the substrate.

[0019] According to at least one embodiment of the semiconductor laser component, at least some of the semiconductor lasers are arranged on a separate substrate. Arranging the semiconductor lasers on separate substrates enables the selection of different substrate materials, each with different properties. For example, the substrate materials differ in their thermal conductivity and / or electrical conductivity.

[0020] Different thermal conductivities can be used to adjust the operating temperature of the semiconductor laser mounted on the substrate. For example, using a material with lower thermal conductivity can achieve a higher operating temperature for the semiconductor laser mounted on the substrate. Furthermore, the different electrical properties can be used to further influence the operating parameters of each semiconductor laser. Different electrical resistance leads, among other things, to different operating currents and / or different operating temperatures for the semiconductor laser mounted on the substrate. Among other things, increased electrical resistance is responsible for further heating of the substrate and thus also for a higher operating temperature of the semiconductor laser mounted on it.

[0021] According to at least one embodiment of the semiconductor laser component, an insulating layer is arranged between at least one semiconductor laser and the substrate. The insulating layer is suitable, for example, for establishing a different thermal resistance and / or a different electrical resistance between a semiconductor laser and an associated substrate. A different thermal resistance leads, among other things, to a different operating temperature of the semiconductor laser and thus influences the main emission wavelength of the associated semiconductor laser. A different electrical resistance leads, in particular, to a different operating current and thus to a changed operating point of the associated semiconductor laser.

[0022] According to at least one embodiment of the semiconductor laser component, the insulating layer is formed with silicon oxide or silicon nitride. Silicon oxide and silicon nitride are advantageously particularly easy to deposit on a given substrate material and are easy to structure using conventional methods.

[0023] According to at least one embodiment of the semiconductor laser component, at least one semiconductor laser is doped with a dopant that modifies an emission wavelength of the semiconductor laser. For example, local doping is carried out with at least one of the following dopants: boron, zinc, carbon, silicon.

[0024] According to at least one embodiment of the semiconductor laser component, the semiconductor lasers are formed in a monolithic semiconductor body. Preferably, all semiconductor lasers are formed in a monolithic semiconductor body. In other words, the semiconductor lasers are combined in a so-called laser bar. A laser bar facilitates alignment with a downstream optical element, such as a beam combiner. Furthermore, the arrangement of the semiconductor lasers in a laser bar enables a particularly compact design of the semiconductor laser component.

[0025] According to at least one embodiment of the semiconductor laser component, the semiconductor lasers are arranged at different lateral distances from one another. Different lateral distances can result in different operating temperatures for the individual semiconductor lasers. For example, a semiconductor laser mounted closer to a heat sink can be operated at a lower operating temperature than a semiconductor laser mounted further away. Different operating temperatures can advantageously result in different main emission wavelengths for the individual semiconductor lasers.

[0026] According to at least one embodiment of the semiconductor laser component, an actuator generates a time-modulated mechanical strain in at least one semiconductor laser. A variable mechanical strain varies, among other things, the main emission wavelength of the associated semiconductor laser.

[0027] According to at least one embodiment of the semiconductor laser component, an actuator is assigned to the semiconductor lasers, each of which generates a temporally modulated mechanical strain of the semiconductor lasers. Preferably, an actuator is assigned to each semiconductor laser. Different variations in the mechanical strain of the semiconductor lasers can further contribute to increasing the spectral bandwidth of the secondary electromagnetic radiation. In particular, the semiconductor lasers are modulated differently and are not coordinated with one another. In other words, the modulation of the semiconductor lasers is advantageously not correlated with one another.

[0028] According to at least one embodiment of the semiconductor laser component, the actuator comprises a piezoelectric element. A piezoelectric element can advantageously be controlled particularly quickly and can generate a particularly high mechanical stress.

[0029] According to at least one embodiment of the semiconductor laser component, a gradient mirror is arranged at an output region of at least one semiconductor laser. A gradient mirror is characterized by locally varying reflectivity. A varying reflectivity, which varies across multiple semiconductor lasers, in turn leads to a different operating point of the semiconductor lasers and thus generates different main emission wavelengths of the semiconductor lasers.

[0030] According to at least one embodiment of the semiconductor laser component, a dielectric mirror is arranged at an output region of at least one semiconductor laser. A dielectric mirror, in particular a distributed Bragg reflector (DBR mirror), has a high reflectivity at a resonant frequency and can therefore also produce a different main emission wavelength for the individual semiconductor lasers. A DBR mirror comprises a plurality of layers with periodically alternating refractive indices. Preferably, the number of alternating layers of the dielectric mirror varies from one semiconductor laser to another, resulting in a variation in reflectivity. For example, the resonant frequencies of the DBR mirrors of several semiconductor lasers each differ by a few nm.

[0031] Within the resonator of at least one semiconductor laser, an optical layer sequence is arranged, the refractive index of which can be changed by applying an external electrical voltage or an electrical current. The optical layer sequence is arranged within the resonator at the coupling-out region. Thus, a change in the optical and / or actual length of the resonator can be generated by means of a time-varying refractive index. In particular, the resonator length is modulated. A time-varying resonator length results, among other things, in an increased primary spectral bandwidth of the semiconductor laser. The optical layer sequence is preferably electrically non-conductive.

[0032] Piezoelectric and / or ferroelectric materials are particularly suitable as materials for the optical layer sequence. The optical layer sequence is formed with a material having a perovskite structure. The optical layer sequence is preferably formed with at least one of the following materials: quartz SiO2, aluminum nitride AlN, lithium niobate LiNbO3, gallium orthophosphate GaPO4, PZT (lead zirconate titanate) Pb (Zr x Ti 1-x ) O3, bismuth titanate Bi4Ti3O 12 , Bismuth Lanthanum Titanate Bi (4-x) La x Ti3O 12 , Bismuth Titanate Niobate Bi3TiNbO9, Strontium Titanate SrTiO3, Barium Strontium Titanate Ba x Sr (1-x) TiO

[0033] According to at least one embodiment of the semiconductor laser component, the semiconductor lasers are mounted on the beam combiner. This advantageously eliminates the need for a substrate. Furthermore, a particularly simple alignment of the semiconductor lasers to the coupling surfaces of the beam combiner is possible, resulting in a very compact design.

[0034] Furthermore, a method for operating at least one semiconductor laser is specified. The method for operating at least one semiconductor laser is particularly suitable for operating a semiconductor laser in a semiconductor laser component described here. This means that all features disclosed in connection with the semiconductor laser component are also disclosed for the method for operating at least one semiconductor laser, and vice versa.

[0035] According to at least one embodiment of the method for operating at least one semiconductor laser, each semiconductor laser has a characteristic curve of its optical output power over its operating time, which initially has a rise range and subsequently a steady-state range. Each semiconductor laser is preferably operated in pulsed mode, so that operation occurs predominantly in its rise range. In the rise range, a threshold for laser operation is exceeded. As soon as the laser threshold is exceeded, increased electromagnetic radiation is emitted from stimulated emission, and the intensity increases at a constant electrical current. However, in a short time window after the laser threshold is exceeded, the resonator is not yet oscillating stably. In this time window, the spectral bandwidth of the semiconductor laser is higher.In the rising region, the semiconductor laser therefore does not yet have a stable operating point and emits electromagnetic radiation with a higher spectral bandwidth than in its steady-state range. To exploit this effect, it is necessary to shut down the semiconductor laser before the oscillations in the resonator have stabilized, thus reducing the spectral bandwidth again. Modulating the semiconductor laser with short pulses for predominantly operation in the unstable operating point thus leads to the emission of electromagnetic radiation with a beneficially increased spectral bandwidth.

[0036] According to at least one embodiment of the method for operating a plurality of semiconductor laser components, at least two semiconductor lasers are operated simultaneously in a pulsed manner in their rise range, or at least two semiconductor lasers are operated sequentially in a pulsed manner in their rise range. "Simultaneously" here and below means simultaneously within a tolerance period of milliseconds, in particular within a period imperceptible to the human eye. By means of simultaneous pulsed operation or sequential pulsed operation of several semiconductor lasers, an observer can perceive electromagnetic radiation with an advantageously increased intensity and a further advantageously increased spectral bandwidth.However, in the case of pulsed operation of a single semiconductor laser to increase its spectral bandwidth, a disadvantageous reduction in the intensity of the emitted electromagnetic radiation would be unavoidable.

[0037] A semiconductor laser component described here is particularly suitable for use in so-called "smart eyewear products" that implement augmented reality (AR) or virtual reality (VR) units. The semiconductor laser components described here can also be used in various projection systems for displaying image content, for example, in glasses, close to the eye, or for projecting an image directly into a human eye.

[0038] Further advantages and advantageous embodiments and developments of the semiconductor laser component emerge from the following embodiments shown in the figures.

[0039] They show: Fig. 1 a schematic plan view of a semiconductor laser component described here according to a first embodiment, Fig. 2 a schematic plan view of a semiconductor laser component described here according to a second embodiment, Fig. 3 a schematic plan view of a semiconductor laser component described here according to a third embodiment, Fig. 4 a schematic plan view of a semiconductor laser component described here according to a fourth embodiment, Fig. 5 a schematic plan view of a semiconductor laser component described here according to a fifth embodiment, Fig. 6 is a diagram of a characteristic curve of the intensity of the emitted electromagnetic radiation of a semiconductor laser over time according to a first embodiment of a method for operating semiconductor lasers described here, Fig. 7 diagrams of characteristic curves of the intensity of the emitted electromagnetic radiation from several semiconductor lasers over time according to a second embodiment of a method for operating semiconductor lasers described here, Fig. 8 diagrams of characteristic curves of the intensity of the emitted electromagnetic radiation from several semiconductor lasers over time according to a third embodiment of a method for operating semiconductor lasers described here, and Fig. 9 a schematic sectional view of a semiconductor laser component described here according to a sixth embodiment.

[0040] Identical, similar, or functionally identical elements are provided with the same reference numerals in the figures. The figures and the relative sizes of the elements depicted in the figures are not to be considered to scale. Rather, individual elements may be exaggerated for clarity and / or clarity.

[0041] Fig. Figure 1 shows a schematic plan view of a semiconductor laser component 1 described here according to a first embodiment. The semiconductor laser component 1 comprises a beam combiner 20 and a plurality of semiconductor lasers 10 on a common substrate 30. The beam combiner 20 comprises a plurality of waveguides 21 embedded in the beam combiner 20. Furthermore, the beam combiner 20 comprises a plurality of coupling surfaces 20A and an output surface 20B.

[0042] The beam combiner 20 is formed from a translucent or transparent material. The waveguides 21 are preferably laser-etched into the material of the beam combiner 20. Such waveguides 21 are characterized by particularly high optical efficiency. The waveguides 21 are arranged such that all electromagnetic radiation coupled in via the coupling surfaces 20A is combined with one another and coupled out at the common coupling surface 20B.

[0043] The semiconductor lasers 10 are arranged on a common substrate 30 and each comprise a resonator 100. The resonators 100 each extend along the semiconductor lasers 10 up to a coupling-out region 60. A gradient mirror or a dielectric mirror, for example, is arranged at the coupling-out region 60. In particular, an optical layer sequence 70 is arranged in the resonator 100 at the coupling-out region 60, the refractive index of which can be changed, for example, by applying an external electrical voltage or an electrical current. Thus, a change in the optical and / or actual length of the resonator 100 can be generated by means of a time-variable refractive index. The refractive index of the optical layer sequence 70 can be modulated by means of a time-variable electrical voltage.A time-modulated resonator length 100A results, among other things, in an increased primary spectral bandwidth of the semiconductor laser 10.

[0044] Each semiconductor laser 10 emits a primary electromagnetic radiation with a primary spectral bandwidth in a direction parallel to its resonator axis 100 and couples this primary electromagnetic radiation into the beam combiner 20. In the beam combiner 20, these primary electromagnetic radiations are guided in the waveguides 21 and superimposed on one another, and finally coupled out as secondary electromagnetic radiation at an output surface 20B of the beam combiner 20. The coupled-out secondary electromagnetic radiation from the beam combiner 20 has a secondary spectral bandwidth that is at least twice the arithmetic mean of the respective primary spectral bandwidths of the electromagnetic radiations of the semiconductor lasers 10.

[0045] An actuator 50 is arranged on the side of a semiconductor laser 10 opposite the output coupling region 60. The actuator 50 comprises a piezo element and serves to modulate the mechanical stress on the semiconductor laser 10. This increases the primary spectral bandwidth of the primary electromagnetic radiation emitted by this semiconductor laser 10.

[0046] Fig. 2 shows a schematic plan view of a semiconductor laser component 1 described here according to a second embodiment of a semiconductor laser component 1. The second embodiment essentially corresponds to the one shown in Fig. 1. However, the semiconductor lasers 10 differ in the length of their resonators 100. Each semiconductor laser 10 has a different resonator length 100A.

[0047] The different resonator lengths 100A result in different main emission wavelengths of the respective semiconductor lasers 10. This makes it possible to further increase the secondary spectral bandwidth of the secondary electromagnetic radiation.

[0048] Fig. 3 shows a schematic plan view of a semiconductor laser component 1 described here according to a third embodiment. Fig. The third embodiment shown in Figure 3 essentially corresponds to the one shown in Fig. 1 shown first embodiment of a semiconductor laser component 1.

[0049] In contrast to the first embodiment, each semiconductor laser 10 is arranged on a separate substrate 30. The arrangement on separate substrates 30 enables a particularly simple influencing of a thermal resistance and / or an electrical resistance between a semiconductor laser 10 and the associated substrate 30.

[0050] For example, each substrate 30 comprises a different material. Thus, a different operating temperature and / or a different electrical behavior of each semiconductor laser 10 can be achieved. This leads to an advantageously increased secondary spectral bandwidth of the secondary electromagnetic radiation. Some of the semiconductor lasers 10 are arranged on a substrate 30 formed from a material with reduced thermal conductivity. These semiconductor lasers 10 have difficulty dissipating the waste heat generated during operation and thus reach an increased operating temperature and thus a changed main emission wavelength.

[0051] Fig. 4 shows a schematic plan view of a semiconductor laser component 1 described here according to a fourth exemplary embodiment. The fourth exemplary embodiment shows a monolithic semiconductor body 11 in which a plurality of semiconductor lasers 10 are formed. Each semiconductor laser 10 comprises a resonator 100. The resonators 100 are aligned parallel to one another. The monolithic semiconductor body 11 is arranged on a substrate 30. A particularly compact design of the semiconductor laser component can be realized by means of a monolithic semiconductor body 11. For example, different semiconductor lasers 10 have different doping in order to each produce a different main emission wavelength.

[0052] Fig. Figure 5 shows a schematic plan view of a semiconductor laser component 1 described here according to a fifth embodiment. The fifth embodiment essentially corresponds to the one shown in Fig. 4 shown fourth embodiment.

[0053] In contrast to the fourth exemplary embodiment, the resonators 100 formed in the monolithic semiconductor body 11 have different lengths 100A. The different lengths 100A of the resonators 100 are realized by means of mesa flanks etched at different locations. Thus, a plurality of different resonator lengths 100A can be realized within the laser bar 11. Using the different resonator lengths 100A, a different main emission wavelength of the different semiconductor lasers 10 can be generated particularly easily, while at the same time, a compact design is maintained due to the arrangement in a monolithic semiconductor body 11.

[0054] Fig. 6 shows a diagram of a characteristic curve of the intensity of the emitted electromagnetic radiation of a semiconductor laser 10 over time according to a first exemplary embodiment of a method for operating semiconductor lasers 10 described here. The Y-axis represents the intensity of the emitted primary electromagnetic radiation of a semiconductor laser 10. The X-axis represents the time axis. The intensity only begins to increase once the laser threshold is exceeded and increases steadily up to a certain limit value. The limit value marks the transition between a rising region A and a subsequent steady-state region B. After leaving the rising region A, the semiconductor laser 10 is in the steady-state region B.

[0055] During the emission of electromagnetic radiation in the rise region A, an increased primary spectral bandwidth with a reduced coherence length can be observed. The operation of the semiconductor laser 10 in the stationary region B corresponds to a stable operating point and occurs with a significantly reduced primary spectral bandwidth and thus with an increased coherence length. Operation of the laser within the rise region A thus advantageously has a low coherence length and a high primary spectral bandwidth. For example, the semiconductor laser 10 can be operated in a pulsed manner in order to achieve exclusive operation in the rise region A. The brightness of the semiconductor laser 10 results from the integral of the intensity over time. If the semiconductor laser 10 is switched off again shortly after switching on in order to achieve the largest possible spectral bandwidth, the value of the integrated brightness is low.As a result, for example, a pixel generated by the semiconductor laser 10 also appears relatively dark.

[0056] Fig. 7 shows diagrams of characteristic curves of the intensity of the emitted electromagnetic radiation from a plurality of semiconductor lasers 10 over time according to a second exemplary embodiment of a method for operating semiconductor lasers 10 described here. To achieve quasi-continuous operation of the semiconductor lasers 10, a plurality of semiconductor lasers 10 can be operated one after the other, each operating only within the rise-up range A. A first semiconductor laser 10 is operated up to the rise-up range A and then switched off, while directly following this, another semiconductor laser 10 is operated, which is also operated only in the rise-up range A and then switched off. By continuing this series, a quasi-continuous operation of a plurality of semiconductor lasers 10 can be achieved.

[0057] Fig. Figure 8 shows diagrams of characteristic curves of the intensity of the emitted electromagnetic radiation from a plurality of semiconductor lasers 10 over time according to a third exemplary embodiment of a method for operating semiconductor lasers 10 described here. To increase the emitted intensity, simultaneous operation of a plurality of semiconductor lasers 10 is conceivable. For example, a plurality of semiconductor lasers 10 are operated only in their rise range A and thus in an operating mode with a high primary spectral bandwidth. The simultaneous superposition of the primary electromagnetic radiation increases the optical intensity of the generated primary electromagnetic radiation.

[0058] Alternatively, a combination of operating modes is possible according to the Fig. 7 and the embodiment shown in the Fig. 8 is possible. Thus, a sequential operation of several semiconductor lasers 10 can be carried out alternately to generate the most continuous emission possible, and a simultaneous emission of several semiconductor lasers 10 can be generated for the highest possible intensity.

[0059] Fig. Figure 9 shows a schematic sectional view of a semiconductor laser component 1 described here according to a sixth exemplary embodiment. The semiconductor laser component 1 shown here comprises a common substrate 30 on which three semiconductor lasers 10 are arranged. An insulating layer 40 is arranged between each semiconductor laser 10 and the substrate 30.

[0060] The insulating layer 40 has different thicknesses and can thus cause different thermal and / or electrical resistances between the semiconductor lasers 10 and the substrate 30. Additionally or alternatively, the insulating layer 40 can be locally structured to further influence thermal and / or electrical resistance.

[0061] By means of the differently designed insulating layer 40, the operating temperature of each semiconductor laser 10 can be specifically influenced. By varying the operating temperatures as much as possible, a further reduction of the coherence length and thus an increase of the primary spectral bandwidth can be achieved. List of reference symbols 1 semiconductor laser component 10 semiconductor lasers 11 semiconductor bodies 100 resonators 100A resonator length 20 beam combiners 20A coupling surfaces 20B Output surface 21 waveguides 30 Substrat 40 Insulation layer 50 actuator 60 decoupling area 70 optical layer sequence A rise range B Inpatient area

Claims

[1] Semiconductor laser device (1) comprising a plurality of semiconductor lasers (10) and a beam combiner (20) configured to combine radiation emitted by the semiconductor lasers (10), wherein - the semiconductor lasers (10) each emit primary electromagnetic radiation of a primary spectral bandwidth in the visible wavelength range, - the primary electromagnetic radiation of the semiconductor lasers (10) is coupled into the beam combiner (20), - a secondary electromagnetic radiation is coupled out of the beam combiner (20), which is formed from a superposition of the primary electromagnetic radiation of the semiconductor lasers (10), and - the secondary electromagnetic radiation has a secondary spectral bandwidth that is at least twice as large as the average of the primary spectral bandwidths, and - within a resonator (100) of at least one semiconductor laser (10) an optical layer sequence (70) is arranged at an output coupling area (60), which is formed with a material having a perovskite structure and whose refractive index can be changed by applying an external electrical voltage or current. [2] Semiconductor laser device (1) according to claim 1, wherein the secondary spectral bandwidth is between 5 nm and 10 nm. [3] Semiconductor laser device (1) according to one of the preceding claims, wherein the beam combiner (20) is a monolithic component. [4] Semiconductor laser device (1) according to one of the preceding claims, wherein the semiconductor lasers (10) have different resonator lengths (100A). [5] Semiconductor laser device (1) according to one of the preceding claims, wherein the semiconductor lasers (10) are arranged on a common substrate (30). [6] Semiconductor laser device (1) according to one of claims 1 to 4, wherein at least a part of the semiconductor lasers (10) are arranged on a separate substrate (30). [7] Semiconductor laser device (1) according to one of claims 5 or 6, wherein a thermal insulating layer (40) is arranged between at least one semiconductor laser (10) and the substrate (30). [8] Semiconductor laser device (1) according to claim 7, wherein the insulating layer (40) is formed with silicon oxide or silicon nitride. [9] Semiconductor laser device (1) according to one of the preceding claims, wherein at least one semiconductor laser (10) has a doping with a dopant material which modifies a principal emission wavelength of the semiconductor laser (10). [10] Semiconductor laser device (1) according to one of the preceding claims, wherein the semiconductor lasers (10) are formed in a monolithic semiconductor body (11). [11] Semiconductor laser device (1) according to one of the preceding claims, wherein the semiconductor lasers (10) are arranged at different lateral distances from each other. [12] Semiconductor laser device (1) according to one of the preceding claims, wherein an actuator (50) generates a time-modulated mechanical stress at at least one semiconductor laser (10). [13] Semiconductor laser device (1) according to one of the preceding claims, wherein the semiconductor lasers (10) are associated with an actuator (50) which generates a time-modulated mechanical stress on the semiconductor lasers (10). [14] Semiconductor laser device (1) according to one of claims 12 or 13, wherein the actuator (50) comprises a piezo element. [15] Semiconductor laser device (1) according to one of the preceding claims, wherein a gradient mirror is arranged at the output coupling area (60) of at least one semiconductor laser (10). [16] Semiconductor laser device (1) according to one of claims 1 to 14, in which a dielectric mirror is arranged at the output coupling area (60) of at least one semiconductor laser (10). [17] Semiconductor laser device (1) according to one of the preceding claims, wherein the semiconductor lasers (10) are mounted on the beam combiner (20).

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