Tolerance optimization of a mobile phone camera lens system

Abstract

In the manufacturing process for the lens system of a mobile phone camera, various types of assembly and manufacturing tolerances, such as tilt and decenter, should be appropriately allocated. Because these tolerances affect manufacturing cost and the expected optical performance, it is necessary to choose a systematic design methodology for determining optimal tolerances. In order to determine the tolerances that minimize production cost while satisfying the reliability constraints on important optical performance indices, we propose a tolerance design procedure for a lens system. A tolerance analysis is carried out using Latin hypercube sampling for evaluating the expected optical performance. The tolerance optimization is carried out using a function-based sequential approximate optimization technique that can reduce the computational burden and smooth numerical noise occurring in the optimization process. Using the proposed design approach, the optimal production cost was decreased by 28.3% compared to the initial cost while satisfying all the constraints on the expected optical performance. We believe that the tolerance analysis and design procedure presented in this study can be applied to the tolerance optimization of other systems.

Optical design of camera optics for mobile phones

“…Unauthenticated Download Date | 6/7/19 5:52 PM because the individual tolerances are at the technological limit [8] . In addition, compensators such as lens longitudinal or lateral displacement to increase overall performance in a separate adjustment step are often not implemented, primarily due to production cost.…”

Taguchi–gray relational analysis of eccentricity and tilt of multilens module mount fabricated by injection compression molding

“…Therefore, for smartphones intended to deliver high-performance photography, the lens mount requires extremely high dimensional accuracy. [8][9][10] Array-type multilens mounts are typically produced using plastic injection compression molding (ICM). In the ICM process, the mold initially closes but not fully, leaving a slight gap.…”

An assembly sensitivity analysis method based on state space model

“…Assembly sensitivity-based tolerance design in computeraided process planning needs to obtain an appropriate set of manufacturing tolerances for the various manufacturing operations involved, considering process capability of the machines and manufacturing allowance for each operation in succession. Aiming at drawbacks of tolerance design (Zhang et al, 2012;Zhang, 1996;Lehtihet et al, 2000;Hong and Chang, 2002), a few authors proposed a series of optimization methods (Peng et al, 2008;Ciarallo and Yang, 1997;Cheng and Maghsoodloo, 1995;Jung et al, 2011). Chen and Chung (1996) introduced a model to determine the inspection precision and the optimal number of repeated measurements to maximize the net expected profit per item.…”