Imaging‐Based Metrics Drawn from Visual Perception of Haze and Clarity of Materials. I. Method, Analysis, and Distance‐Dependent Transparency

Abstract

A versatile imaging‐based method is presented for quantifying the transparency of materials based on “illumination diffusion” (ID), representing scattering‐ and refraction‐induced change in the spatial distribution of transmitted light intensity. Samples are backlit through a graticule mask, with analysis performed by comparative evaluation of graticule images recorded as‐is and viewed through a sample, mimicking visual perception. ID‐haze is quantified as the reduction of contrast, while ID‐sharpness is derived from imaged knife‐edge acuity. Measurements are performed for diverse materials, including clarified polyolefins, silica‐filled amorphous polymers, semicrystalline films, and etched polymer sheets. Comparisons with the respective haze and clarity values obtained using a common ASTM D1003 haze‐meter are made in terms of their quantitative correlation and suitability for applications. In particular, unlike conventional instruments, ID‐based analysis captures the variation of transparency with sample‐to‐object “airgap” distance. Gratifyingly, ID‐haze generally features a one‐to‐one correlation with standard ASTM haze, when determined at a specific distance. The presented method also enables sensitive detection of local defects—differentiating them from large‐area characteristics—and accurately extracts the contribution of luminescence to loss of transparency. ID‐based method therewith offers unique opportunities for application‐ and airgap‐specific transparency analysis, and advanced options for optical process‐ and quality control.

A Portable Technology for Measuring Haze Levels in Thick Laminated Glass Panels

“…2). This principle has been previously employed in portable technology for measuring haze in thin films, as documented by Busato et al (2021). In our approach, we extend this principle to accommodate the unique challenges presented by thick glass laminates.…”

From Unregulated Networks to Designed Microstructures: Introducing Heterogeneity at Different Length Scales in Photopolymers for Additive Manufacturing

“…In addition to light scattering techniques (e.g., haze measurement) that provide data on optical properties, spectroscopy techniques can be employed to estimate the heterogeneity size and distribution. Such techniques can also help monitor the onset and progress of phase separation in photosensitive materials. − Combining spectroscopic techniques with controlled photocuring systems, measuring, and studying the conversion of monomers during the phase-separation process also becomes possible. ,, …”

Development of an image-based measurement instrument for gloss characterization

“…Therefore, 'Michelson contrast haze' (H MC ) is proposed as an alternative metric for haze, inspired by the transparency haze metric of Busato et al They calculate transparency haze as the Michelson contrast between two specified regions at each side of the edge in the ESF. 50,51 Accordingly, H MC is determined from the signal lines as the Michelson contrast (MC) between both sides of the edges of the source aperture image. The metric is expressed in Haze Units (HU):…”