High-Power 1.5 μm Tapered Distributed Bragg Reflector Laser Diodes for Eye-Safe LIDAR

Micro-integrated high-power narrow-linewidth external-cavity tapered diode laser at 762 nm for daylight imaging

“…For laser-based daylight imaging/sensing application, pulsed mode operation of the laser is usually required [2][3][4]. The frame rate of commercially available Si-based cameras is from a few tens to a few thousand frames per second with a resolution around 1 megapixel.…”

“…Narrow-linewidth, high-power, and diffraction-limited diode lasers are attractive for daylight imaging/sensing due to their compactness, low cost, and long lifetime [3,4]. Diffractionlimited high-power diode lasers have been available from the red to the near infrared spectral range since the introduction of tapered diode lasers [5][6][7].…”

“…Diffractionlimited high-power diode lasers have been available from the red to the near infrared spectral range since the introduction of tapered diode lasers [5][6][7]. Narrow-linewidth emission of these high power tapered devices have been achieved by either etching a grating in the semiconductor material, such as distributed feedback (DFB)/distributed Bragg reflector (DBR) feedback technique [4,6,8], or using a master-oscillator power amplifier (MOPA) layout [9,10], or with an external cavity feedback with a frequency selective element [11,12]. The DFB/DBR techniques are well developed from 900 to 1200 nm; very recently, this technique has been applied to tapered diode lasers with wavelengths down to 783 nm.…”

“…For laser-based daylight imaging/sensing application, the laser is usually operated in pulsed mode [2][3][4]. Normally, high power narrow-linewidth tapered diode lasers and laser systems are operated in continuous wave (CW) mode [5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21].…”

Eye-Safe Aerosol and Cloud Lidar Based on Free-Space Intracavity Upconversion Detection

“…Despite its success in continuous aerosol and cloud measurement, the use of a laser has also brought about the issue of eye safety. Fortunately, lasers operating at ~1.5 µm possess the maximum permissible exposure (MPE) up to 1 J/cm 2 , which is over two orders of magnitude higher than the visible or 1 µm lasers, making them suitable light sources for eye-safe aerosol and cloud lidars [10][11][12].…”