Patent ID: 11921028
Assignee: MENARINI SILICON BIOSYSTEMS S.P.A.
Field: Measurement (Instruments)
Classification: CPC G  B | IPC B  G

Claim 0:
1. A method of performing optical analysis and manipulation of particles in suspension in a fluid contained in a microchamber, the microchamber having an internal volume for containing the particles in suspension in the fluid, the internal volume being delimited by interior surfaces of oppositely disposed first and second sheets defining bottom and top surfaces of the microchamber, an exterior surface of the second sheet being an optical inspection surface, the method comprising:
cooling the fluid contained in the microchamber to a first temperature using a cooling device thermally coupled to the first sheet, wherein the first temperature is below ambient temperature;
generating a thermal flow across the optical inspection surface to heat and maintain the optical inspection surface at a second temperature, the second temperature being higher than a condensation temperature of ambient humidity surrounding the optical inspection surface; and
performing an optical inspection of the particles in suspension through the optical inspection surface while the fluid in the microchamber is maintained at the first temperature and while the optical inspection surface is maintained at the second temperature,
wherein the second sheet has a thermal conductivity that is at least one order of magnitude lower than a thermal conductivity of the first sheet such that heating of the fluid by the generation of the thermal flow across the optical inspection surface is limited or avoided, and
wherein the second sheet has a thickness determined by, H
   
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       Δ
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where Hlid is the thickness of the second sheet, Tdp is the temperature of condensation of ambient humidity contained in the air which surrounds the optical inspection surface, To is an operating temperature desired inside the microchamber, ΔTmax is the maximum increase in temperature tolerable inside the microchamber relative to a target operating temperature, σlid is the thermal conductivity of the second sheet, σbuf is a thermal conductivity of the fluid to be contained in the microchamber, and Hc is a thickness of the microchamber as measured by the distance between the interior surfaces of the first and second sheets, wherein ΔTmax=(Tbuf−To)max and Tbuf is the temperature of the fluid.