Optical inspection of smartphone camera modules by near-infrared low-coherence interferometry
Date of Issue2016
School of Mechanical and Aerospace Engineering
High-resolution cameras used for smartphones are comprised of multiple aspheric lenses, a spectral filter, and a semiconductor image sensor, which are packaged together into a single module with tight geometrical tolerances. We investigated the technical possibility of near-infrared low-coherence interferometry for nondestructive geometrical inspection of the complex camera module to examine the inside packaging state. This tomographic scheme enabled us to measure the relative axial position of each inside component and also the lateral surface profile of the image sensor, allowing for comprehensive three-dimensional quality assurance of the whole camera module during the packaging process.
© 2016 Society of Photo-Optical Instrumentation Engineers (SPIE). This paper was published in Optical Engineering and is made available as an electronic reprint (preprint) with permission of SPIE. The published version is available at: [http://dx.doi.org/10.1117/1.OE.55.9.091404]. One print or electronic copy may be made for personal use only. Systematic or multiple reproduction, distribution to multiple locations via electronic or other means, duplication of any material in this paper for a fee or for commercial purposes, or modification of the content of the paper is prohibited and is subject to penalties under law.