Laser Inspection Calibration Baseline for Thermal Signature Analysis,
Abstract
Thermal signature analysis method for the interpretation of Vanzetti laser inspection sensor data, when applied to solder joint process analysis, will be superior to existing statistical threshold methods. A thorough understanding of the laser inspection process and parameters is required along with accurate system calibration. This paper will provide a general definition of the laser inspection process and its equipment, a brief history of laser inspection and details of the system baseline development program. The system baseline development program was designed to establish a repeatable system baseline for system effects on sensor output from system component fluctuations, ambient temperature fluctuations, and target irregularities. In addition, a system transfer function was produced to derive optimum thermal signature amplitudes. A system signal-to-noise threshold was established. As a result of this program, a calibration method was developed holding signature repeatability to 2%. As a result of this calibration method and subsequent thermal signature analysis, success has been measured in the detection of small subsurface solder voids.
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 01, 1987
- Accession Number
- ADP005188
Entities
People
- Douglas H. Ensign