Preferred embodiments of the present invention are directed to systems for phase measurement which address the problem of phase noise using combination s of a number of strategies including, but not limited to, common-path interferometry, phase referencing, active stabilization and differential measurement. Embodiment are directed to optical devices for imaging small biological objects with light. These embodiments can be applied to the field s of, for example, cellular physiology and neuroscience. These preferred embodiments are based on principles of phase measurements and imaging technologies. The scientific motivation for using phase measurements and imaging technologies is derived from, for example, cellular biology at the s ub- micron level which can include, without limitation, imaging origins of dysplasia, cellular communication, neuronal transmission and implementation of the genetic code. The structure and dynamics of sub-cellular constituents cannot be currently studied in their native state using the existing methods and technologies including, for example, x-ray and neutron scattering. In contrast, light based techniques with nanometer resolution enable the cellul ar machinery to be studied in its native state. Thus, preferred embodiments of the present invention include systems based on principles of interferometry and/or phase measurements and are used to study cellular physiology. These systems include principles of low coherence interferometry (LCI) using optic al interferometers to measure phase, or light scattering spectroscopy (LSS) wherein interference within the cellular components themselves is used, or i n the alternative the principles of LCI and LSS can be combined to result in systems of the present invention本発明の好ましい実施例は、共通路干渉計検査、位相基準化、能動的安定化及び差動測定を含むが、それらに限定されない、多数の戦略の組み合わせを用いて、位相ノイズの問題に取り組む位相測定用システムに向けられている。実施例は光を用いて小さな生物学的対象を画像形成する光学デバイスに向けられている。これらの実施例は、例えば、細胞生理学及び神経科学の分野に適用出来る。これらの好ましい実施例は位相測定及び画像形成技術の原理に基づく。位相測定及び画像形成技術を使う科学的動機付けは、例え
