Design of an optical system consisting of a special telecentric lens for side-scattering measurement on individual cells

Abstract

The alignment and collection of side-scattered light in scattering measurement on individual cells, based on hydraulic focusing technology, is always time-consuming and troublesome. Even small errors result in a poor SNR. This paper presents an optical system including a specially designed telecentric lens to focus stray light and scattering signals. The lens has a compact structure, small distortion and aberration, and large depth of focus. Thus scattering signals can be extracted easily and effectively, even when the spatial filters are out of focus or tilted with respect to the optical axis by human error. Also, the stray light in the side direction is analyzed, and the results show good performance of this special telecentric lens. Scattering results on 4.91-and 16.32-m polystyrene beads verify that this optical system can be well applied for sidescattering signal detection.

Speckle contrast diffuse correlation tomography of complex turbid medium flow

“…These issues are beyond the scope of the current paper, but can be addressed in the future through computer simulations, possible free-space corrections, 17 and telecentric zoom lens incorporation. 18,19 …”

Improved high-throughput quantification of luminescent microplate assays using a common Western-blot imaging system

“…Unlike entocentric lenses, with telecentric lenses the chief rays from an object are parallel to the optical axis of the lens, meaning magnification and perspective is consistent regardless of the objects perpendicular distance to the optical axis. Telecentric lenses have been used for biological imaging and sensing applications previously [4] , [5] , however, they are significantly more complex and expensive than entocentric lenses, and thus would mitigate any of the cost savings generated by using a Western-blot imaging system instead of purchasing a luminometer. Here we present an improved method of luminescence assay quantification using a common, un-modified, Western-blot imaging system that corrects for this well position effect, increasing precision of measurements across a microplate.…”

Investigation of an Autofocusing Method for Visible Aerial Cameras Based on Image Processing Techniques

“…Finally, a rough focal plane position is obtained. The camera drives the focusing mirror to the approximate focal plane position [10,14].…”

“…Even though optoelectronic autocollimation method is an established technology, this application is too complex to be realized. Furthermore, it can only calibrate the position 2 International Journal of Aerospace Engineering of infinity target, and it cannot calibrate the position of actual target, which further limits the application of such technique [8][9][10]. (3) Image processing methods [6], in which the position of the focal plane will be estimated from the actual images: the focusing is an "intelligent" method, which is to say the focusing criterion is flexible, and different focus evaluation function can be automatically chosen according to the requirement.…”