US 4,155,009 A · Thickness measurement instrument with memory storage of multiple calibrations

Abstract

An improved backscatter instrument for the nondestructive measurement of coatings on a substrate. A memory having selectable memory areas, each area having stored intelligence available which is determinative of the shape of a functional plot of coating thickness versus backscatter counts per minute unique for each particular combination of emitting isotope, substrate material, coating material and physical characteristics of the measuring instrument. A memory selector switch connects a selected area of memory to a microprocessor operating under program control whereby the microprocessor reads the intelligence stored at the selected area and converts the backscattered count of the coating being measured into indicia of coating thickness.

Claims17

Dependent claims

A backscatter apparatus for nondestructively measuring the thickness of a coating on a substrate comprising:

radioactive isotope means for irradiating the coating with particles;
means for counting backscattered particles;
a microprocessor operating under control of a program to convert the count of backscattered particles into indicia of coating thickness in accordance with a functional relationship between thickness and count of backscattered particles per minute for a given isotope, given substrate material, given coating material and given geometry of a measurement situs;
a memory means having multiple selectable areas, each area having available stored intelligence of a particular functional relationship in a format readable by the microprocessor;
means for selecting an area in memory;
and
means responsive to the selecting means for connecting the selected area in memory to the microprocessor whereby when so connected the microprocessor under program control reads the intelligence stored at the selected area in memory and makes the conversion in accordance with this intelligence.

4 more elements

A method for non-destructively measuring the thickness of a coating on a substrate using beta particle backscattering techniques comprising:

irradiating the coating with particles from a radioactive isotope;
counting the particles backscattered from the coating and substrate;
selecting an area in a memory means having multiple selectable areas, each area having available stored intelligence of a functional relationship between thickness and count of backscattered particles per minute for a given isotope, given substrate material, given coating material and given geometry of a measurement situs;
and
converting the count of backscattered particles into indicia of coating thickness in accordance with the intelligence of the functional relationship stored at the selected area in memory.

2 more elements

Dependencies are inferred from the claim text.

Thickness measurement instrument with memory storage of multiple calibrations

Life of this patent

Thickness measurement instrument with memory storage of multiple calibrations

Life of this patent

Abstract

Claims17