Simultaneous multi-dimensional spatial frequency modulation imaging

Abstract

One of the primary challenges in advanced manufacturing (AM) is the lack of efficient optical metrics for ensuring quality control over the manufacturing process. Many current imaging techniques have excessive data requirements and require computationally intensive post-processing to effectively characterize various AM environments. Spatial frequency modulated imaging (SPIFI) addresses many of these issues with the following benefits: it is compatible with long working distance optics, provides a large field-of-view, features single element detection, and can provide enhanced resolution. Here, we demonstrate SPIFI with enhanced resolution in multiple dimensions for the first time. This is achieved by incorporating multiple linear extended excitation sources oriented with axes at arbitrary angles with respect to each other. The system utilizes a single modulation mask enabling facile implementation within existing imaging systems such as those found in laser AM systems.

Enhanced resolution dispersion optimized multiphoton microscopy with spatial frequency modulation imaging

“…However for a line scanning architecture where the line is scanned across 256 steps, a 30 fps image can be taken with a pixel dwell time of 130 µs and 13,020 pulses per pixel. Since SPIFI was first introduced as an imaging technique, [18][19][20] it has been demonstrated and extended to multiple applications including multiphoton imaging, 21 multi-cursor 2D imaging, 22 random access multiphoton imaging, 23 and Coherent Anti-stokes Raman Spectroscopy (CARS). 24 The SPIFI modulation mask is modeled in polar coordinates according to:…”

Cascaded domain multiphoton spatial frequency modulation imaging

“…Since SPIFI was first introduced as an imaging technique, 22 it has been demonstrated and extended to multiple imaging modalities including fluorescent imaging, 22,23 multiphoton excitation fluorescence imaging, [24][25][26] second harmonic generation imaging, 26,27 phase imaging, 28,29 and localization microscopy. 30 Extending SPIFI to provide simultaneous SIM benefits in two dimensions has also been explored using 2D modulation schemes, 31,32 random-access imaging, 33 parallel line image acquisition, 34 single pixel tomographic imaging, [35][36][37][38] multi-cursor 2D imaging, 32 random access multiphoton imaging, 33 and coherent anti-Stokes Raman spectroscopy. 27 Here we introduce a system that employs SPIFI in two domains to (1) achieve enhanced resolution multiphoton microscopy and (2) compensate for second order dispersion with a rapid, facile, and easily repeatable method.…”