Abstract: A device to determine the contrast sensitivity of an individual's visual system by means of a series of tests in a measurement session, comprising a means for producing real time digital images, corresponding to modulated visual stimuli; and a display means for presenting said images to an individual's eye, wherein said stimuli may be modulated around an average stimulus in any direction of the color space and may be configured in their spatial and temporal characteristics for each measurement session. Said stimuli are usually chosen in the cardinal directions of the color space and respond to a sinusoidal grid pattern with spatial and temporal modulation, and with a two dimensional gaussian envelope.

Abstract: A method for authentication of an individual based upon biometric mode and biometric instance data comprising the steps of: storing at least a first biometric data having at least one biometric data mode and at least two biometric data instances capable of identifying an individual associated with the first biometric data; creating an at least second biometric data having the at least one biometric data mode and the at least two biometric data instances capable of identifying a specific individual associated with the second biometric data; determining which of said at least one biometric data mode and said at least two biometric data instances are to be compared; in accordance with predetermined rules; and comparing the at least second biometric data to said at least first biometric data to determine whether the selected biometric data mode and selected biometric data instances of the at least first biometric data corresponds to the selected at least one of biometric data mode and selected at least two biomet