Subjective Perception and Objective Measurement
The Standardization of Visual Effects in Glass
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Current glass industry standards provide clear tolerances for readily quantifiable physical properties to assist with the evaluation of visual quality. Yet, these standards provide less definitive guidelines for properties that are subject to human perception. Such properties pose a complex challenge, as they require a reproducible means of quantifying an effect. Three visual effects (anisotropy, white haze, and color consistency) are considered with respect to present standards, underlying causes, and correlating physical properties. Methods of controlling subjective evaluation of these effects, including the standardization of viewing parameters and establishment of acceptable effect ranges to define defects, are outlined. The pairing of these methods with novel physical property measurement systems is proposed. Referencing techniques and models of soft metrology, in particular its application to color evaluation, can assist with the establishment of new glass industry standards to prevent visual effects from being dismissed as irreconcilable phenomena
Introduction - Industry Standards
The glass industry has developed an array of standards to assist with the evaluation of visual quality. While these standards thoroughly
Background - Qualitative Issues
Some of the qualitative topics that are often discussed in the glass industry are anisotropy, white haze and color consistency.
Generally speaking, anisotropy is the difference in a material’s properties
Method - Quantification of Qualitative Issues
When one of these visual effects is deemed objectionable after installation on the building, thereby triggering a rejection and replacement of the glass, the cost and disruption can be significant
Conclusion and Future Work
As professionals that are responsible for the quality of materials, including physical, performance, and visual properties, we are left lacking a standard method to evaluate a range of visual effects
We would like to thank Peter Arbour, Dan Popadynec, and Israel Berger for their guidance on this paper.
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