The Zeiss Humphrey Matrix Perimeter utilizes Welch Allyn Frequency Doubling Technology. The Zeiss Humphrey Matrix represents a significant breakthrough in Visual Field testing by combining early glaucoma detection capabilities, tools to characterize glaucoma and basic glaucoma management tools. The Humphrey Matrix also doubles as an in-office glaucoma screener with 35 second supra-threshold testing. The Humphrey Matrix also provides up to 69 stimuli to characterize visual field defects to facilitate accurate diagnoses.