Polarization-controlled VCSEL characterization
Novel one-shot method enables the full performance efficiency of the VCSELs to be exploited while assuring safe operation
At Laser World of Photonics 2022, Instrument Systems presents its latest VTC 4000 infrared camera for the near-field analysis of narrow-band emitters, e.g. VCSELs or lasers. Industry-standard VCSELs emit in more than one polarization state, each with different polarization angles, thus impeding error-free measurement. Thanks to a new process, the VTC 4000 simultaneously measures the spatial polarization of single emitters of an array and supplies the necessary information to reduce the polarization dependency of the measurement setup.
VCSELs are components with an intrinsic single-longitudinal mode, and normally exhibit complex polarization properties. The light they emit is typically linearly polarized along one of two orthogonal directions. If the temperature or bias current changes, abrupt polarization switching can be observed. VCSELs thus emit in more than one polarization state, so that their polarization angle cannot be controlled. This polarization dependency should be taken into account in the measurement of magnitudes and absolute power, in order to minimize the error budget of the VCSEL test system and guarantee highly accurate readings.
The VTC 4000 near-field camera from Instrument Systems was specially developed for the ultrafast, precise 2D analysis of VCSEL arrays. It permits the polarization-controlled, simultaneous characterization of all relevant parameters for the single emitters of the array. Due to a unique calibration concept, the 2D quality analysis is performed with an unprecedented measurement accuracy. This concept is based on flat-field and polarization correction, and corrects the polarization dependence of the optical system. The VTC 4000 thus calibrated enables absolute measurement of power and the polarization properties of each single emitter within the field of view in a one-shot process.
Like all measuring equipment from Instrument Systems, the VTC 4000 camera is traceably calibrated to national standards (PTB) and delivers readings with absolute precision. Its minimum error budget for power measurement results in a measurement accuracy that is unmatched by any other VCSEL measuring system currently on the market.
Visit Instrument Systems at Booth A6.221 at Laser World of Photonics in Munich from 26 – 29 April 2022.
Reference: Frank Münchow and Karthik Iyer (Instrument Systems): Polarization-controlled VCSEL characterization – Novel one-shot method enables the full performance efficiency of the VCSELs to be exploited while assuring safe operation, PhotonicsViews 19(2), April/May 2022, pp. 32–36, in print; DOI: 10.1002/phvs.202200014
Issue 2/2022 (April/May) will be out April 22nd. You want the printed issue in your mailbox? Please find the form for paid or qualified subscriptions for below: