Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Phase gradient microscopy in thick tissue with oblique back-illumination   Phase contrast techniques, such as differential interference contrast (DIC)
microscopy, are widely used to provide morphological images of unstained
biological samples. The trans-illumination geometry required for these
techniques has restricted their application to thin samples. We introduce
oblique back-illumination microscopy (OBM), a method of collecting en face
phase gradient images of thick scattering samples, enabling near video-rate in
vivo phase imaging with a miniaturized probe suitable for endoscopy.

8
The categories of this paper are: hep-ex
14
The categories of this paper are: math-ph
17
The categories of this paper are: q-fin
21
The categories of this paper are: adap-org
25
The categories of this paper are: patt-sol
28
The categories of this paper are: alg-geom
4
The categories of this paper are: cond-mat
22
The categories of this paper are: chao-dyn
26
The categories of this paper are: bayes-an
19
The categories of this paper are: eess
0
The categories of this paper are: hep-ph
16
The categories of this paper are: stat
18
The categories of this paper are: econ
7
The categories of this paper are: hep-th
34
The categories of this paper are: chem-ph
31
The categories of this paper are: ao-sci