Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Fast binarized time-reversed adapted-perturbation (b-TRAP) optical
  focusing inside scattering media   Light scattering inhibits high-resolution optical imaging, manipulation and
therapy deep inside biological tissue by preventing focusing. To form deep
foci, wavefront-shaping and time-reversal techniques that break the optical
diffusion limit have been developed. For in vivo applications, such focusing
must provide high gain, high speed, and a large number of spatial modes.
However, none of the previous techniques meet these requirements
simultaneously. Here, we overcome this challenge by rapidly measuring the
perturbed optical field within a single camera exposure followed by adaptively
time-reversing the phase-binarized perturbation. Consequently, a
phase-conjugated wavefront is synthesized within a millisecond, two orders of
magnitude shorter than the digitally achieved record. We demonstrated real-time
focusing in dynamic scattering media, and extended laser speckle contrast
imaging to new depths. The unprecedented combination of fast response, high
gain, and large mode count makes this work a major stride toward in vivo deep
tissue optical imaging, manipulation, and therapy.

6
The categories of this paper are: astro-ph
34
The categories of this paper are: chem-ph
14
The categories of this paper are: math-ph
13
The categories of this paper are: quant-ph
20
The categories of this paper are: acc-phys
26
The categories of this paper are: bayes-an
25
The categories of this paper are: patt-sol
30
The categories of this paper are: q-alg
12
The categories of this paper are: nucl-th
5
The categories of this paper are: gr-qc
10
The categories of this paper are: q-bio
0
The categories of this paper are: hep-ph
15
The categories of this paper are: nucl-ex
29
The categories of this paper are: funct-an
18
The categories of this paper are: econ
33
The categories of this paper are: plasm-ph