Patent ID: 8619205

Claim:
A three-dimensional video recognition system comprising a video display device which can display a right-eye image and a left-eye image alternately in a time division manner on a screen of the display device, and active shutter glasses which can alternately switch between a light transmitting state and a light shielding state of right and left lens sections in synchronization with the right-eye image and the left-eye image, wherein each of the active shutter glasses includes a first Î»/4 plate, a first linear polarizing element, a liquid crystal cell, and a second linear polarizing element in this order from an outer surface side of each of the active shutter glasses, wherein the video display device includes a third linear polarizing element provided on an observation surface side of the video display device, the three-dimensional video recognition system further comprising a second Î»/4 plate, wherein the second Î»/4 plate is arranged between the third linear polarizing element and the first Î»/4 plate, wherein, when an angle formed between a transmission axis of the first linear polarizing element and an in-plane slow axis of the first Î»/4 plate is defined as Ï†1, and when an angle formed between a transmission axis of the third linear polarizing element and an in-plane slow axis of the second Î»/4 plate is defined as Ï†2, the following expressions (1) and (2) or the following expressions (3) and (4) are satisfied: 40Â°â‰¦Ï†1â‰¦50Â°â€ƒâ€ƒ(1) 40Â°â‰¦Ï†2â‰¦50Â°â€ƒâ€ƒ(2) 130Â°â‰¦Ï†1â‰¦140Â°â€ƒâ€ƒ(3) 130Â°â‰¦Ï†2â‰¦140Â°â€ƒâ€ƒ(4) where Ï†1 is measured as viewed from the side of the first Î»/4 plate and is measured in a counterclockwise direction taken as a positive direction with reference to a direction of the transmission axis of the first linear polarizing element, and where, similarly, Ï†2 is measured as viewed from the side of the second Î»/4 plate and is measured in a counterclockwise direction taken as a positive direction with reference to a direction of the transmission axis of the third linear polarizing element.