A system and method for optically detecting samples held in a solution requires the use of a holding plate that has as many as one-thousand through-hole wells, or more. The solution is suspended in these through-hole wells under surface tension between opposed surfaces of the holding plate. A pneumatic pump is then engaged with the plate to establish a differential pressure (&Dgr;p) between the upper and lower surfaces of the solution that is equal to approximately two tenths of a pound per square inch (0.2 psi). The result is the formation of a convex meniscus on a surface of the solution that causes light passing into the solution to converge and concentrate. This concentration of light, in turn, facilitates optical detection of samples in the solution.