Lens Performance in a Nonstandard or Unstable Thermal Environment.

摘要

Analytic techniques for determining the optical performance of a camera lens under the influence of steady state and transient thermal conditions are developed. A computer program using a simplified model of the lens to determine certain key physical and optical parameters is developed. The steady state analysis finds these parameters at a new temperature directly, while the transient analysis employs finite difference equations which are solved numerically to find the temperature inside the lens as a function of position and time prior to determining the parameters. With this information, the Modulation Transfer Function (MTF), a measurement of lens performance, is determined using existing methods. Based on limited experimental evidence, correct trends of lens performance under various thermal conditions can be predicted.