Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Molecular contrast on phase-contrast microscope   An optical microscope enables image-based findings and diagnosis on
microscopic targets, which is indispensable in many scientific, industrial and
medical settings. Majority of microscope users are accustomed to standard
benchtop microscopes, but it fails to give molecular contrast of the specimen
which otherwise requires expensive specialized instruments to measure,
accompanied by chemical or optical damages to the sample and/or slow imaging
speed. Here, we report on a simple optical instrument, comprising of a
semiconductor amplitude-modulated mid-infrared quantum cascade laser, that is
attached to a standard microscope to deliver the additional molecular contrast
of the specimen on top of its conventional microscopic image. We attach this
instrument, termed molecular-contrast unit, to a standard phase-contrast
microscope, and demonstrate high-speed label-free molecular-contrast
phase-contrast imaging of biological cells under low-power optical
illumination. Our simple molecular-contrast unit can empower existing standard
microscopes of various users, by delivering a convenient accessibility to the
molecular world.

29
The categories of this paper are: funct-an
5
The categories of this paper are: gr-qc
37
The categories of this paper are: supr-con
18
The categories of this paper are: econ
7
The categories of this paper are: hep-th
14
The categories of this paper are: math-ph
35
The categories of this paper are: mtrl-th
33
The categories of this paper are: plasm-ph
0
The categories of this paper are: hep-ph
10
The categories of this paper are: q-bio
25
The categories of this paper are: patt-sol
1
The categories of this paper are: cs
23
The categories of this paper are: solv-int
21
The categories of this paper are: adap-org
15
The categories of this paper are: nucl-ex
2
The categories of this paper are: math