Reflectivity/emissivity measurement probe insensitive to variations in probe-to-target distance
AssigneeCi Systems Ltd.
InventorsYoram Naor, Benjamin J Brosilow
Life of this patent
Estimating the term…
Abstract
Apparatuses and methods for accurately measuring the reflectivity of a target surface, under conditions where the distance between a measuring probe and the target surface is not fixed. At least two measurements of the target reflectivity are taken under different conditions, and then these two or more measurements are combined in order to calculate the target reflectivity in a way which is independent of the probe-to-target distance. In particular, the different conditions are such that each measurement samples radiation reflected from the target surface at a different distribution of angles. The apparatus can also be used to accurately measure the distance between the probe measurement head and a target surface.
Claims25
An apparatus for determining the reflectance of a target surface comprising:
- a. a radiation source for projecting radiation onto the target surface;
- b. a radiation detector positioned to detect radiation reflected off the target surface at least two different locations of said radiation detector relative to said radiation source and to the target surface and to produce at least two respective signals V1 and V2 such that each signal is indicative of a radiation intensity reflected at a respective angular distribution that is different for each signal, wherein at least two of said angular distributions overlap at least partially;
- whereby signals V1 and V2 are used to calculate the reflectivity of the target surface.
An apparatus for determining the reflectance of a target surface comprising:
- a. a radiation source for projecting radiation onto the target surface;
- b. a radiation detector positioned to detect radiation reflected off the target surface at least two different locations of said radiation detector relative to said radiation source and relative to the target surface and to produce at least two respective signals V1 and V2 such that each signal is indicative of a radiation intensity reflected at a respective angular distribution that is different for each signal, wherein at least two said angular distributions overlap at least partially, and wherein signals V1 and V2 differ from each other in that each respective angular distribution is determined by a respective different aperture.
A method for determining the reflectance of a target surface comprising the step of:
- a. detecting radiation reflected from the target surface, at least two different locations of a radiation detector relative to a source of said radiation and relative to the target surface, in at least two different respective angular distributions, wherein each angular distribution produces a respective different reflected radiation intensity value and wherein two of said at least two different angular distributions overlap at least partially;
- and
- b. calculating the target reflectivity from the at least two different reflected radiation intensity values.
An apparatus for determining the reflectance of a target surface comprising:
- a. a radiation source for projecting radiation onto the target surface;
- b. a radiation detector positioned to detect radiation reflected off the target surface at least two different locations of said radiation detector relative to said radiation source and relative to the target surface and to produce at least two signals V1 and V2 such that each signal is indicative of a radiation intensity reflected at a respective angular distribution that is different for each signal;
- wherein signals V1 and V2 are used to calculate the reflectivity of the target surface without explicit use of a reference reflectivity.
An apparatus for determining the reflectance of a target surface comprising:
- a. a radiation source for projecting radiation onto the target surface;
- b. a radiation detector positioned to detect radiation reflected off the target surface at least two different locations of said radiation detector relative to said radiation source and relative to the target surface and to produce at least two signals V1 and V2 such that each signal is indicative of a radiation intensity reflected at a respective angular distribution that is different for each signal, wherein signals V1 and V2 differ from each other in that each respective angular distribution is determined by a respective different aperture, and wherein signals V1 and V2 are used to calculate the reflectivity of the target surface without explicit use of a reference reflectivity.
A method for determining the reflectance of a target surface comprising the step of:
- a. projecting radiation onto the target surface;
- b. detecting radiation reflected from the target surface, at least two different locations of a radiation detector relative to a source of said radiation and relative to the target surface, in at least two different respective angular distributions, each angular distribution producing a respective different reflected radiation intensity value;
- and
- b. calculating the target reflectivity from the at least two different reflected radiation intensity values without explicit use of a reference reflectivity.
Dependencies are inferred from the claim text.