Temporal super-resolution microscopy using a hue-encoded shutter

Abstract

Limited time-resolution in microscopy is an obstacle to many biological studies. Despite recent advances in hardware, digital cameras have limited operation modes that constrain frame-rate, integration time, and color sensing patterns. In this paper, we propose an approach to extend the temporal resolution of a conventional digital color camera by leveraging a multi-color illumination source. Our method allows for the imaging of single-hue objects at an increased frame-rate by trading spectral for temporal information (while retaining the ability to measure base hue). It also allows rapid switching to standard RGB acquisition. We evaluated the feasibility and performance of our method via experiments with mobile resolution targets. We observed a time-resolution increase by a factor 2.8 with a threefold increase in temporal sampling rate. We further illustrate the use of our method to image the beating heart of a zebrafish larva, allowing the display of color or fast grayscale images. Our method is particularly well-suited to extend the capabilities of imaging systems where the flexibility of rapidly switching between high frame rate and color imaging are necessary.

Investigating Depth Domain Adaptation for Efficient Human Pose Estimation

“…Before we delve into the details of our proposed method, we briefly recall assumptions of the HESM method developed in [3] and the limitations that prevent it from being directly applicable to fluorescence microscopy. In [3], the light captured by the camera (Fig. 2 A, B) was assumed to be either reflected by the imaged scene or transmitted through a sample.…”

“…2 E, F). Although each fluorescent species' individual emission spectrum is independent of the illumination spectrum, the fluorophores' combined emission spectrum depends on the spectral overlap of the illumination [3] assumes a bright field microscopy setup, where the illumination light is transmitted through (or reflected by) a sample then captured by an RGB camera. The transmitted (or reflected) spectrum directly depends on the combination of the illumination spectrum and the sample's spectral transmittance.…”

“…In this paper, we propose to extend the hue-encoded shutter method presented in [3] to fluorescence microscopy and to apply it to light-sheet microscopy [4]. The method in [3] increases the flexibility of microscopes by allowing to rapidly switch between color imaging and fast imaging, or to do both simultaneously, within regions of interest. Briefly, that method uses a multi-color LED illumination source that is synchronized to a color camera.…”

“…The individual color frames are then processed to convert the color channels into multiple (monochrome) time frames. The monochrome requirement of [3] cannot be translated directly to fluorescence microscopy, as the spectral signature of the illumination is lost in the excitation-emission process at the heart of fluorescence. To overcome this limitation, we propose to use multiple co-localized fluorophore species with different emission spectra.…”

“…The main contributions of the present paper are (i) the adaptation of the method in [3] to fluorescence microscopy; (ii) an improved temporal super-resolution reconstruction algorithm to compensate for slight model mismatches; (iii) demonstration of the applicability to light-sheet microscopy for biological applications.…”