Holography-based structured light illumination for temporal focusing microscopy

Abstract

In this Letter, we present a holography-based structured light illumination (SLI) method to enhance the resolution of widefield temporal focusing microscopy (TFM). In the system, a digital micromirror device is employed to simultaneously disperse the incoming femtosecond laser to induce temporal focusing at the focal plane and generate designed structured patterns via a Lee hologram. As the generated structured patterns do not contain the zeroth order beam, it improves the contrast and modulation frequency. Mathematical models have been derived to calculate the electric fields at the focal plane and to explain the effects of improved optical cross-sectioning capability. Imaging experiments have been devised and performed on fluorescent beads and mouse kidney sections; the results demonstrate enhanced axial confinement and improved suppression of out-of-focus fluorescence. The new SLI method realizes high-resolution TFM and can be readily applied to other microscopy platforms for biophotonics applications.

Super-Resolution Enabled Widefield Quantum Diamond Microscopy

“…29 Among these devices, the DMD has the advantages of high speed (up to 32.5 kHz), high resolution (e.g., 3840 × 2160 pixels), and low cost and has therefore been frequently used in high-speed imaging systems. 34,35 For example, by combining a DMD with digital holography, our team has demonstrated super-resolution imaging (155 nm) at an imaging rate of 26.7 frames per second. 29 Built upon our experience in DMD-based light microscopy, 34,36−45 by integration with conventional diamond quantum sensing, we present a dynamic super-resolved WQDM.…”

“…On the other hand, structured illumination microscopy (SIM), which can achieve subdiffraction limit imaging via a widefield system, has been widely used in biology owing to its simplicity in operation and low photodamage to samples. ,− In general, a 2-fold spatial resolution improvement can be achieved by shifting the unobservable high spatial frequency information to an observable low spatial frequency region via structured light illumination (SLI). , Commonly used SLI devices include optical gratings, liquid crystal-based spatial light modulators, and digital micromirror devices (DMDs) . Among these devices, the DMD has the advantages of high speed (up to 32.5 kHz), high resolution (e.g., 3840 × 2160 pixels), and low cost and has therefore been frequently used in high-speed imaging systems. , For example, by combining a DMD with digital holography, our team has demonstrated super-resolution imaging (155 nm) at an imaging rate of 26.7 frames per second …”

Mode-locking operation of an Er-doped fiber laser with (PEA)2(CsPbBr3)n−1PbBr4 perovskite saturable absorbers

“…Ultrashort pulse lasers have a wide variety of applications in the fields of laser sensing, laser processing, biotechnology and others. [1][2][3][4][5] In general, the passive mode-locking method is one of the most practical for obtaining ultrafast lasers due to its low cost, self-starting characteristics and insensitivity to the environment. 6,7 Saturable absorbers (SAs) are key components in passive mode-locked fiber laser systems, whose transmittance increases with an increase in the input laser intensity and, thus, they could modulate a continuous wave into a pulsed wave.…”

Fast 3D super-resolution imaging using a digital micromirror device and binary holography

“… 5 In the holography mode, designed binary holograms are displayed on the DMD to manipulate the wavefront of the incident laser to perform fast beam shaping and random-access scanning. 6 – 9 In comparison to the projection mode, the holography mode offers improved flexibility and precision in generating and controlling the position, phase, and intensity of multiple foci at the back focal plane of an objective lens, which may be used to design and create complex two-dimensional (2D) and 3D structured patterns with improved contrast.…”