Diffraction of digital micromirror device gratings and its effect on properties of tunable fiber lasers

Abstract

A digital micromirror device (DMD) is a kind of widely used spatial light modulator. We apply DMD as wavelength selector in tunable fiber lasers. Based on the two-dimensional diffraction theory, the diffraction of DMD and its effect on properties of fiber laser parameters are analyzed in detail. The theoretical results show that the diffraction efficiency is strongly dependent upon the angle of incident light and the pixel spacing of DMD. Compared with the other models of DMDs, the 0.55 in. DMD grating is an approximate blazed state in our configuration, which makes most of the diffracted radiation concentrated into one order. It is therefore a better choice to improve the stability and reliability of tunable fiber laser systems.

Demonstration of multi-wavelength tunable fiber lasers based on a digital micromirror device processor

“…The measured total loss of bulk optics from input and output collimators is around 11.6 dB, which is mainly due to the lens reflection loss, the diffraction loss, and the insertion loss from the blazed grating and DMD processor. The largest loss among them is caused by the DMD [12,13]. The total cavity loss, as one of the key parameters, not only influences the output power and SMSR, but also the EDFA pump current thresholds needed for lasing [14].…”

“…After several recirculations the high-quality single-mode laser is achieved. It is important to note that in order to increase the SMSR of signals, the approximate blazed condition of the DMD over the whole C-band should be satisfied, which we have discussed in [12].…”

DMD-based super-resolution structured illumination microscopy visualizes live cell dynamics at high speed and low cost

“…To better understand the results obtained by measurements, we chose to model the DMD and simulated the diffraction pattern depending on the angle of incidence α [24]. To accomplish this, the DMD needs to be described mathematically, and the electric field reflected from its surface has to be calculated for different positions and states of the mirrors.…”

Confocal retinal imaging using a digital light projector with a near infrared VCSEL source

“…DMD diffraction has been characterized in the design of laser-based custom projection systems used for wavelength tuning, 19 tunable fiber lasers, 20 quantitative phase imaging, 21 and fluorescent microscopy. 22 It is generally desired to couple as much of the illumination power into the zero order diffracted output (the specular reflection) of the micromirror when tilted into an ON state.…”