Abstract: A vertical cavity surface emitting laser device includes: an optical resonator; a photodiode; and a contact arrangement. The optical resonator includes: two distributed Bragg reflectors (DBRs) and an active region between the DBRs. The photodiode has a light absorption region in the optical resonator. The contact arrangement provides drive current to pump the optical resonator, and contacts the photodiode. The active region has an InxGa1-xAs layer, where 0?x<1. The light absorption region has an InyGa1-yAs layer, where 0<y<1, and y>x. The InyGa1-yAs layer is an intrinsic layer of the light absorption region. The InyGa1-yAs layer is 15-50 nm thick. The light absorption region has an undoped layer with a material different from the InyGa1-yAs layer. The InyGa1-yAs layer is immediately adjacent to the undoped layer. An intrinsic zone of the light absorption region is at least 70 nm thick.

Abstract: A method reduces false-positive particle counts detected by an interference particle sensor module, which has a laser and a light detector. The method including: emitting laser light; providing a high-frequency signal during the emission of the laser light, a modulation frequency of the high-frequency signal being between 10-500 MHz; detecting an optical response by the light detector in reaction to the emitted laser light while providing the high-frequency signal, which is arranged such that a detection signal caused by a macroscopic object positioned between a first and second distance is reduced in comparison to a detection signal caused by the macroscopic object at the same position without providing the high-frequency signal. The high-frequency signal is provided to a tuning structure of the particle sensor module which is arranged to modify a resonance frequency of an optical resonator comprised by the laser sensor module upon reception of the high-frequency signal.

Abstract: A vertical cavity surface emitting laser includes four contacts and an optical resonator (having two Bragg reflectors, a photodiode, and an active layer between the Bragg reflectors). The second Bragg reflector has three parts. The first part has a pair of layers with different refractive indices and a second conductivity type. The second part has a pair of layers with different refractive indices and a first conductivity type. The third part has a pair of layers with different refractive indices and the second conductivity type. A light absorption structure of the photodiode is between the second and third parts. The first and second electrical contacts provide a current to pump the resonator. The light absorption structure is outside the current path. The third and fourth electrical contacts contact the photodiode. The second and third electrical contact respectively contact the first and second parts and are separated by a semiconductor layer.

Abstract: A laser device includes a laser diode configured to emit radiation, an output power of the radiation being dependent on a laser diode driving current, and a photodiode configured to receive the radiation emitted by the laser diode. A photodiode current induced in the photodiode by the received radiation is dependent on a power of the received radiation. The laser device further includes circuitry configured to measure the photodiode current for a laser diode driving current and calculate a laser threshold current of the laser diode from the measured photodiode current as a measure of an actual laser threshold current of the laser diode. The circuitry is further configured to detect a malfunction or degradation of the laser diode.

Abstract: A Vertical Cavity Surface Emitting Laser (VCSEL) includes a VCSEL array, a multitude of detectors, a first electrical laser contact, and at least one second electrical laser contact. The VCSEL array comprises a multitude of laser diodes, each laser diode including an optical resonator having a first distributed Bragg reflector, a second distributed Bragg reflector and an active layer for light emission, the active layer being arranged between the first distributed Bragg reflector and the second distributed Bragg reflector. The first electrical laser contact and the at least one second electrical laser contact are arranged to provide an electrical drive current to electrically pump the optical resonators of the laser diodes. Each detector is arranged to generate an electrical self-mixing interference measurement signal associated to at least one laser diode upon reception of the laser light.

Abstract: A vertical cavity surface emitting laser (VCSEL) has first and second electrical contacts, and an optical resonator. The optical resonator has first and second distributed Bragg reflectors (DBRs), an active layer, a distributed heterojunction bipolar phototransistor (DHBP), and an optical guide. The DHBP has a collector layer, light sensitive layer; a base layer; and an emitter layer. There is an optical coupling between the active layer and the DHBP for providing an active carrier confinement by the DHBP. The optical guide guides an optical mode within the optical resonator during operation. The optical guide is outside a current flow which can be provided by the first and second electrical contacts during operation of the VCSEL. The optical guide is outside a layer sequence between the first and second electrical contacts in the vertical direction of the VCSEL. The optical guide has an oxide aperture arranged in the second DBR.

Abstract: A vertical cavity surface emitting laser device includes: an optical resonator; a photodiode; and a contact arrangement. The optical resonator includes: two distributed Bragg reflectors (DBRs) and an active region between the DBRs. The photodiode has a light absorption region in the optical resonator. The contact arrangement provides drive current to pump the optical resonator, and contacts the photodiode. The active region has an InxGa1-xAs layer, where 0?x<1. The light absorption region has an InyGa1-yAs layer, where 0<y<1, and y>x. The InyGa1-yAs layer is an intrinsic layer of the light absorption region. The InyGa1-yAs layer is 15-50 nm thick. The light absorption region has an undoped layer with a material different from the InyGa1-yAs layer. The InyGa1-yAs layer is immediately adjacent to the undoped layer. An intrinsic zone of the light absorption region is at least 70 nm thick.

Abstract: A laser device includes a laser diode configured to emit radiation, an output power of the radiation being dependent on a laser diode driving current, and a photodiode configured to receive the radiation emitted by the laser diode. A photodiode current induced in the photodiode by the received radiation is dependent on a power of the received radiation. The laser device further includes circuitry configured to measure the photodiode current for a laser diode driving current and calculate a laser threshold current of the laser diode from the measured photodiode current as a measure of an actual laser threshold current of the laser diode. The circuitry is further configured to detect a malfunction or degradation of the laser diode.

Abstract: A method reduces false-positive particle counts detected by an interference particle sensor module, which has a laser and a light detector. The method including: emitting laser light; providing a high-frequency signal during the emission of the laser light, a modulation frequency of the high-frequency signal being between 10-500 MHz; detecting an optical response by the light detector in reaction to the emitted laser light while providing the high-frequency signal, which is arranged such that a detection signal caused by a macroscopic object positioned between a first and second distance is reduced in comparison to a detection signal caused by the macroscopic object at the same position without providing the high-frequency signal. The high-frequency signal is provided to a tuning structure of the particle sensor module which is arranged to modify a resonance frequency of an optical resonator comprised by the laser sensor module upon reception of the high-frequency signal.

Abstract: A Vertical Cavity Surface Emitting Laser (VCSEL) includes a VCSEL array, a multitude of detectors, a first electrical laser contact, and at least one second electrical laser contact. The VCSEL array comprises a multitude of laser diodes, each laser diode including an optical resonator having a first distributed Bragg reflector, a second distributed Bragg reflector and an active layer for light emission, the active layer being arranged between the first distributed Bragg reflector and the second distributed Bragg reflector. The first electrical laser contact and the at least one second electrical laser contact are arranged to provide an electrical drive current to electrically pump the optical resonators of the laser diodes. Each detector is arranged to generate an electrical self-mixing interference measurement signal associated to at least one laser diode upon reception of the laser light.

Abstract: A vertical cavity surface emitting laser includes four contacts and an optical resonator (having two Bragg reflectors, a photodiode, and an active layer between the Bragg reflectors). The second Bragg reflector has three parts. The first part has a pair of layers with different refractive indices and a second conductivity type. The second part has a pair of layers with different refractive indices and a first conductivity type. The third part has a pair of layers with different refractive indices and the second conductivity type. A light absorption structure of the photodiode is between the second and third parts. The first and second electrical contacts provide a current to pump the resonator. The light absorption structure is outside the current path. The third and fourth electrical contacts contact the photodiode. The second and third electrical contact respectively contact the first and second parts and are separated by a semiconductor layer.

Abstract: A vertical cavity surface emitting laser (VCSEL) has first and second electrical contacts, and an optical resonator. The optical resonator has first and second distributed Bragg reflectors (DBRs), an active layer, a distributed heterojunction bipolar phototransistor (DHBP), and an optical guide. The DHBP has a collector layer, light sensitive layer; a base layer; and an emitter layer. There is an optical coupling between the active layer and the DHBP for providing an active carrier confinement by the DHBP. The optical guide guides an optical mode within the optical resonator during operation. The optical guide is outside a current flow which can be provided by the first and second electrical contacts during operation of the VCSEL. The optical guide is outside a layer sequence between the first and second electrical contacts in the vertical direction of the VCSEL. The optical guide has an oxide aperture arranged in the second DBR.

Abstract: The invention describes a laser device comprising between two and six mesas (120) provided on one semiconductor chip (110), wherein the mesas (120) are electrically connected in parallel such that the mesas (120) are adapted to emit laser light if a defined threshold voltage is provided to the mesas (120). Two to six mesas (120) with reduced active diameter in comparison to a laser device with one mesa improve the yield and performance despite of the fact that two to six mesas need more area on the semiconductor chip thus increasing the total size of the semiconductor chip (110). The invention further describes a method of marking semiconductor chips (110). A functional layer of the semiconductor chip (110) is provided and structured in a way that a single semiconductor chip (110) can be uniquely identified by means of optical detection of the structured functional layer. The structured layer enables identification of small semiconductor chips (110) with a size below 200 ?m×200 ?m.

Abstract: The disclosure relates to a Vertical Cavity Surface Emitting Laser (100) comprising a first electrical contact (105), a substrate (110), a first Distributed Bragg Reflector (115), an active layer (120), a second Distributed Bragg Reflector (130) and a second electrical contact (135). The Vertical Cavity Surface Emitting Laser comprises at least two current aperture layers (125) arranged below or above the active layer (120), wherein each of the current aperture layers (125) comprises one AlyGa(1?y)As-layer, wherein a first current aperture layer (125a) of the at least two current aperture layers (125) is arranged nearer to the active layer (120) as a second current aperture layer (125b) of the at least two current aperture layers (125), wherein the first current aperture layer (125a) comprises a first current aperture (122a) with a bigger size as a second current aperture (122b) of the second current aperture layer (125b). The disclosure also relates to a method of manufacturing such a VCSEL (100).

Abstract: The disclosure relates to a Vertical Cavity Surface Emitting Laser (100) comprising a first electrical contact (105), a substrate (110), a first Distributed Bragg Reflector (115), an active layer (120), a second Distributed Bragg Reflector (130) and a second electrical contact (135). The Vertical Cavity Surface Emitting Laser comprises at least two current aperture layers (125) arranged below or above the active layer (120), wherein each of the current aperture layers (125) comprises one AlyGa(1-y)As-layer, wherein a first current aperture layer (125a) of the at least two current aperture layers (125) is arranged nearer to the active layer (120) as a second current aperture layer (125b) of the at least two current aperture layers (125), wherein the first current aperture layer (125a) comprises a first current aperture (122a) with a bigger size as a second current aperture (122b) of the second current aperture layer (125b). The disclosure also relates to a method of manufacturing such a VCSEL (100).

Abstract: The invention describes a laser device comprising between two and six mesas (120) provided on one semiconductor chip (110), wherein the mesas (120) are electrically connected in parallel such that the mesas (120) are adapted to emit laser light if a defined threshold voltage is provided to the mesas (120). Two to six mesas (120) with reduced active diameter in comparison to a laser device with one mesa improve the yield and performance despite of the fact that two to six mesas need more area on the semiconductor chip thus increasing the total size of the semiconductor chip (110). The invention further describes a method of marking semiconductor chips (110). A functional layer of the semiconductor chip (110) is provided and structured in a way that a single semiconductor chip (110) can be uniquely identified by means of optical detection of the structured functional layer. The structured layer enables identification of small semiconductor chips (110) with a size below 200 ?m×200 ?m.

Abstract: The invention describes a laser device (100) comprising between two and six mesas (120) provided on one semiconductor chip (110), wherein the mesas (120) are electrically connected in parallel. The laser device (100) is adapted such that degradation of at least one mesa (120) results in a decreased laser power emitted by the laser device (100) in a defined solid angle when driven at the defined electrical input power. The laser device (100) is adapted such that eye safety of the laser device (100) is guaranteed during life time of the laser device (100). Eye safety may be guaranteed by designing the semiconductor structure or more general layer structure of mesas (120) of the laser device (100) in a way that degradation of one or more layers of the layer structure results in a reduction of the maximum optical power emitted in a defined solid angle.

Abstract: The invention relates to a Vertical Cavity Surface Emitting Laser (100) comprising a first electrical contact (105), a substrate (110), a first Distributed Bragg Reflector (115), an active layer (120), a second Distributed Bragg Reflector (130) and a second electrical contact (135). The Vertical Cavity Surface Emitting Laser comprises at least one AlyGa(1-y)As-layer with 0.95?y?1 with a thickness of at least 40 nm, wherein the AlyGa(1-y )As-layer is separated by means of at least one oxidation control layer (119, 125b). The invention further relates to a laser device (300) comprising such a VCSEL (100) preferably an array of such a VCSELs (100) which are driven by an electrical driving circuit (310). The invention also relates to a method of manufacturing such a VCSEL (100).

Abstract: The invention describes a laser device comprising between two and six mesas (120) provided on one semiconductor chip (110), wherein the mesas (120) are electrically connected in parallel such that the mesas (120) are adapted to emit laser light if a defined threshold voltage is provided to the mesas (120). Two to six mesas (120) with reduced active diameter in comparison to a laser device with one mesa improve the yield and performance despite of the fact that two to six mesas need more area on the semiconductor chip thus increasing the total size of the semiconductor chip (110). The invention further describes a method of marking semiconductor chips (110). A functional layer of the semiconductor chip (110) is provided and structured in a way that a single semiconductor chip (110) can be uniquely identified by means of optical detection of the structured functional layer. The structured layer enables identification of small semiconductor chips (110) with a size below 200 ?m×200 ?m.

Abstract: The invention relates to a Vertical Cavity Surface Emitting Laser (100) comprising a first electrical contact (105), a substrate (110), a first Distributed Bragg Reflector (115), an active layer (120), a second Distributed Bragg Reflector (130) and a second electrical contact (135). The Vertical Cavity Surface Emitting Laser comprises at least one AlyGa(1-y)As-layer with 0.95?y?1 with a thickness of at least 40 nm, wherein the AlyGa(1-y)As-layer is separated by means of at least one oxidation control layer (119, 125b). The invention further relates to a laser device (300) comprising such a VCSEL (100) preferably an array of such a VCSELs (100) which are driven by an electrical driving circuit (310). The invention also relates to a method of manufacturing such a VCSEL (100).