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Spatial frequency modulated imaging (SPIFI) is a powerful imaging method that when used in conjunction with multiphoton contrast mechanisms has the potential to improve the spatial and temporal scales that can be explored within a single nonlinear optical microscope platform. Here we demonstrate, for the first time to our knowledge, that it is possible to fabricate inexpensive masks using femtosecond laser micromachining that can be readily deployed within the multiphoton microscope architecture to transform the system from a traditional point-scanning system to SPIFI and gain the inherent advantages that follow.

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Pore‐scale mineral dissolution reactions are of fundamental importance for sustaining life and determining the fate of chemicals in Earth's near‐surface environments. However, experimental investigations are largely limited to macroscopic approaches due to difficulties in controlling and observing geochemical processes at the pore scale. Here, we present an experimental method using both femtosecond laser ablation and hydrofluoric (HF) etching techniques to fabricate reactive microdevices in a natural silicate mineral, anorthite. The femtosecond laser minimizes damage to the mineral during ablation and HF etching successfully removes a thin amorphous layer induced by laser irradiation. Anorthite dissolution rates under far‐from‐equilibrium conditions (10−8.14 to 10−8.43 mol m−2 s−1), quantified by total calcium flux from the microfluidic device, correspond to previous laboratory‐measured rates also measured under far‐from‐equilibrium conditions, thereby supporting the reactive mineral microdevice as a valuable tool for mineral dissolution studies.

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.