Most of current miniscope systems limit imaging areas to under 1 mm 2 ( 11), confining measurements to a subset of cells within a single brain region. Multiscale measurements are still beyond reach. However, the imaging performance of current miniscope systems remains restricted by their optics, similar to their standard fluorescence microscopy counterparts. In particular, miniaturized head-mounted fluorescence microscopes, i.e., “miniscopes” ( 11), have made substantial progress and enabled unprecedented access to neural signals, revealing previously unknown views of neural circuits underlying diverse behaviors, such as navigation, memory storage, learned motor programs, and social interactions. For example, the FOVs for cortex-wide imaging systems are often set by the curved cortical surface that requires additional mechanisms to be compensated for, otherwise resulting in excessive out-of-focus blurs in the peripheral FOV regions ( 3).Īnother technological focus is toward miniaturization driven by the need for long-term in vivo imaging in freely behaving animals. In addition, the achievable field of view (FOV) is further constrained by the system’s shallow depth of field (DOF) in many bioimaging applications ( 3, 7). This results in an undesirable trade-off between the achievable space-bandwidth product (SBP) and the complexity of the optical design ( 9, 10), as evident by mesoscopes developed on the basis of both the sequential ( 5, 6) and multiscale ( 7) lens design principles. However, the development of these mesoscopic imaging systems is confounded by the scale-dependent geometric aberrations of optical elements ( 9). Recent progress, such as macroscopes ( 3), Mesolens microscope ( 5), two-photon mesoscope ( 6), RUSH ( 7), and COSMOS ( 8), are only beginning to bridge these scales. For example, perception and cognition arise from extended brain networks spanning millimeters to centimeters ( 3) yet rely on computations performed by individual neurons only a few micrometers in size ( 4). A major focus for recent technological developments is aimed at overcoming the barrier of scale ( 2). We further quantify the effects of scattering and background fluorescence on phantom experiments.įluorescence microscopy is an indispensable tool in fundamental biology and systems neuroscience ( 1). We experimentally validate the mesoscopic imaging capability on 3D fluorescent samples. Its expanded imaging capability is enabled by computational imaging that augments the optics by algorithms. The CM 2 features a compact lightweight design that integrates a microlens array for imaging and a light-emitting diode array for excitation. Here, we present a Computational Miniature Mesoscope (CM 2) that overcomes these bottlenecks and enables single-shot 3D imaging across an 8 mm by 7 mm field of view and 2.5-mm DOF, achieving 7-μm lateral resolution and better than 200-μm axial resolution. However, conventional microscopes/miniscopes are inherently constrained by their limited space-bandwidth product, shallow depth of field (DOF), and inability to resolve three-dimensional (3D) distributed emitters. The need for recording in freely behaving animals has further driven the development in miniaturized microscopes (miniscopes). Fluorescence microscopes are indispensable to biology and neuroscience.
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