Manufacturable and reliable electrically pumped micro-electromechanically tunable vertical cavity surface emitting lasers for low-cost ophthalmic swept source optical coherence tomography

The ultimate goal of this effort is to bring advanced ophthalmic swept source optical coherence tomographySS OCTimaging to low cost broadly accessible environmentsSS OCT is a powerful non invasive diagnostic imaging modalityand an increasingly valuable tool in the early detection and monitoring of a number of retinal diseasesas well as in anterior eye and whole eye imagingA key driver of high cost of for these systems has been the cost and complexity of the wavelength swept laser sourcewhich is the most technologically advanced component of SS OCT systemMost commercial wavelength swept sources are assembled discretely from separate optical components requiring precision sub micron alignmentsOver the lastyearshoweverfunded in part by NEI grant REYPraevium Research has developed a monolithic chip scale wavelength swept laser source based on electrically pumped micro electromechanical systems vertical cavity surface emitting lasersMEMS VCSELsThese devices can be fabricated and tested in lots of thousands on a wafer scalecreating the possibility of fabrication costs of a few dollars per deviceIn additionthe record imaging range and high and flexible imaging speed of MEMS VCSELs has enabled retinal imaginganterior eye imaging and whole eye imaging for ocular biometry to be performed in a single multi modal instrument for the first timeThe rapid tuning speed has been combined with advanced image processing to enable dye free OCT angiographyOCTAwhich is capable of imaging key early markers associated with both wet and dry AMD and DRApplications of this new OCTA technology continue to emergeManufacturability and reliability challenges remain significant barriers to volume commercialization of MEMS eVCSELsThese challenges constitute a classicvalley of deathbetween technology demonstration and commercial productSSOCT imaging places stringent requirements on MEMSeVCSEL tuning rangetuning speedpolarizationand spectral puritywhich are without precedent in other semiconductor laser applicationsAdditionallythese critical parameters must be achieved with sufficient yield to meet aggressive price targets necessary for high volume low cost applicationsand be maintained over a several thousand hour lifetimeThis work therefore seeks to address and overcome the manufacturability and reliability challenges associated with MEMS eVCSELsand lay a foundation for high volume commercialization of these devices This projectif successfulwill impact public health by bringing advanced ophthalmic swept source optical coherence tomographySS OCTimaging to broadly accessible low cost environmentsSSOCT is powerful non invasive imaging modality that is increasingly valuable in the early detection and monitoring of retinal diseasesas well as in anterior eye imaging and whole eye imagingBroad access to the most advanced SS OCT technology will prevent blindnessand improve eye care in a larger patient population