Wave-front analysis of personal eye protection

Abstract

Shack-Hartmann wave-front sensing has been successfully applied to many fields of optical testing including the human eye itself. We propose wave-front measurement for testing protective eye wear for production control and investigation of aberrations. Refractive power data is derived from the wave-front data and compared to a subjective measurement technique based on a focimeter. Additional image quality classification was performed with a multivariate model using objective parameters to resample a subjectively determined visual quality. Wave-front measurement advances optical testing of protective eye wear and may be used for objective quality control.

Quality control of injection molded eyewear by non-contact deflectometry

“…To quantify the accuracy, the measured and analyzed surface data of the reference standard was compared to an interferometric measurement which outperformed the PMD sensor in terms of absolute accuracy. For validation and investigation of conditions between the cavities of the tool, we additionally compared the results to a previously published method in transmission [6]. Cavity one was produced and polished with a fully automated polishing technique.…”

“…We compared the results from the PMD-sensor with a previously published wave-front system in order to find a correlation between topography and transmission measurement [6]. We estimated differences between the four cavities and their polishing techniques.…”

“…The wave-front system was introduced in a previous publication and was crosschecked and validated to the OB, which is currently used in the production process for quality check of the spectacles. The WF setup is based on a Shack-Hartmann sensor and allows investigation of wave-front aberrations in addition to refractive power data and image quality classification for safety spectacles [6]. However, both optical transmission techniques do not allow a retrospective classification of mold surface quality or injection molding behavior.…”

Deflectometric analysis of high volume injection molds for production of occupational eye wear

“…Protective effect and optical performance should be both addressed adequately [7] [8]. In addition to the refractive power and low order aberrations such as axis error and prismatic effect (caused by any manufacturing fault, e.g.…”

“…Other potential reasons for optical aberrations are deficient tools or molds and process parameters of injection molding such as temperature, pressure and polycarbonate viscosity. Optical aberrations can be detected by sophisticated optical testing of the spectacle, such as wave-front sensing [7]. Poor optical quality of the spectacle, due to outworn mold shape or mold surface, is one of the reasons for rejection in optical or cosmetic quality control and harms the creation of value and decreases the production efficiency.…”