Journal: Light, Science & Applications

Article Title: Spectral-acoustic-coordinated astigmatic metalens for wide field-of-view and high spatiotemporal resolution 3D imaging

doi: 10.1038/s41377-025-02180-7

Figure Lengend Snippet: a Experimental setup. A broadband source undergoes spectro-temporal encoding for time-frequency multiplexing. The resulting discrete chirped sub-pulses are directed through a 2-axis AOD and a blazed grating (BG) for spectral-dual-AO scanning. The beam then passes through the wide-FOV astigmatic metalens (AML) to enhance spatial detection capability. Echoes are collected by a photomultiplier tube (PMT) for 3D reconstruction. COL, collimating lens; PH, pinhole; HWP, half-wave plate; M, mirror; BPF, bandpass filter. b Schematic of spectral-dual-AO cascade scanning. The y AOD swiftly transitions after each spectral scan to ensure rate matching, while the x AOD operates similarly, forming a three-axis scanning configuration. c Impact of rate mismatch on the effective number of acquired points. (i) Rate matching ( β = 1) ensures FPAR = PPAR, maximizing acquisition efficiency; (ii) Rate mismatch ( β = 2) reduces FPAR to half of PPAR due to redundant spectral scans. d Schematic of beam divergence angle expansion induced by the BG. e Schematic of the output beams evolution after diffraction by the BG for 3 adjacent spectral channels: (i) without ML, (ii) with NML, and (iii) with AML. The AML corrects beam astigmatism while simultaneously expanding the spectral scanning FOV

Article Snippet: The target’s echo signals first pass through a bandpass filter (BPF) (THORLABS, FBH1550-40) to suppress most of the ambient stray light by narrowband spectral filtering.

Techniques: Multiplexing