Method and system for real-time wide-field dynamic temperature sensing

A system for real-time wide-field dynamic temperature sensing of an object, comprising:

• an illumination unit configured to produce wide-field illumination to upconverting nanoparticles at the object plane;
• an objective collecting light emitted by the upconverting nanoparticles;
• a beam splitter dividing a collected light into a reflected component and a transmitted component;
• a spatiotemporal integrator imaging the reflected component into a first image;
• a spatial encoder encoding the object into spatially encoded frames, a rotating mirror temporally shearing resulting spatially encoded, and a camera spatiotemporally integrating a resulting spatially encoded and temporally sheared object into a second image;
• and
• a processing unit reconstructing the object from the first and the second images,
• wherein the system is described in a forward model as:
• E=TM I(x,y,t) (1), where E is a concatenation of measurements [E1, αE2]T, M is a linear operator [1, αSC]T, and α is a scalar factor that balances an energy ratio between the two images during measurements;
• after data acquisition, E is used to retrieve a datacube of the object by leveraging a spatiotemporal sparsity of the object and prior knowledge of each operator;
• wherein, based on a plug-and-play alternating direction method of multipliers (PnP-ADMM), for reconstruction of the datacube, the processing unit solves a minimization problem as follows
• I
• ^
• =
• arg
• ⁢
• min
• I
• ⁢
• {
• 1
• 2
• ⁢
• 
• TMI
• -
• E
• 
• 2
• 2
• +
• R
• ⁡
• (
• I
• )
• +
• I
• +
• (
• I
• )
• }
• where ∥·|22 represents a l2 norm,
• 1
• 2
• ⁢
• 
• TMI
• -
• E
• 
• 2
• 2
• is a fidelity term representing a similarity between measurements and an estimated result, R(·) is an implicit regularizer that promotes sparsity in the object, I+(·) represents a non-negative intensity constraint;
• wherein, for each (x,y) point, an area under a normalized intensity decay curve is integrated to obtain a photoluminescence lifetime value and a photoluminescence lifetime map from the reconstructed datacube;
• and
• wherein the system generates lifetime-determined temperature maps using a temperature distribution, T(x,y) obtained as follows:
• T
• ⁡
• (
• x
• ,
• y
• )
• =
• c
• t
• +
• 1
• S
• a
• ⁢
• ∫
• I
• ^
• (
• x
• ,
• y
• ,
• t
• )
• I
• ^
• (
• x
• ,
• y
• ,
• 0
• )
• ⁢
• dt
• where ct is a constant, and Sa is an absolute temperature sensitivity.