Three-dimensional video recognition system, video display device and active shutter glasses

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 λ/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, and a second λ/4 plate provided on the observation surface side of the third linear polarizing element, and
• wherein, when an angle formed between a transmission axis of the first linear polarizing element and an in-plane slow axis of the first λ/4 plate is defined as φ1, and when an angle formed between a transmission axis of the third linear polarizing element and an in-plane slow axis of the second λ/4 plate is defined as φ2, the following expressions (1) and (2) or the following expressions (3) and (4) are satisfied:
• 40°≦φ1≦50° (1)
• 40°≦φ2≦50° (2)
• 130°≦φ1≦140° (3)
• 130°≦φ2≦140° (4)
• where φ1 is measured as viewed from the side of the first λ/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, φ2 is measured as viewed from the side of the second λ/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.

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,
• 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, and
• a front plate which is arranged on a front surface side of the video display device,
• wherein each of the active shutter glasses includes a first λ/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,
• wherein the front plate includes a second λ/4 plate, and
• wherein, when an angle formed between a transmission axis of the first linear polarizing element and an in-plane slow axis of the first λ/4 plate is defined as φ1, and when an angle formed between a transmission axis of the third linear polarizing element and an in-plane slow axis of the second λ/4 plate is defined as φ2, the following expressions (1) and (2) or the following expressions (3) and (4) are satisfied:
• 40°≦φ1≦50° (1)
• 40°≦φ2≦50° (2)
• 130°≦φ1≦140° (3)
• 130°≦φ2≦140° (4)
• where φ1 is measured as viewed from the side of the first λ/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, φ2 is measured as viewed from the side of the second λ/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.

A video display device that can be used together with active shutter glasses, each including a first λ/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, and can display a right-eye image and a left-eye image alternately in a time division manner on a screen of the display device, the video display device comprising:

• a third linear polarizing element provided on an observation surface side of the video display device, and a second λ/4 plate provided on the observation surface side of the third linear polarizing element,
• wherein, when an angle formed between a transmission axis of the third linear polarizing element and an in-plane slow axis of the second λ/4 plate is defined as φ2, the following expression (1) or (2) is satisfied:
• 40°≦φ2≦50° (1)
• 130°≦φ2≦140° (2)
• where φ2 is measured as viewed from the side of the second λ/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.

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 a right-eye image and a left-eye image which are displayed alternately in a time division manner, each of the active shutter glasses comprising

• a λ/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, when an angle formed between a transmission axis of the first linear polarizing element and an in-plane slow axis of the λ/4 plate is defined as φ1, the following expression (1) or (2) is satisfied:
• 40°≦φ1≦50° (1)
• 130°≦φ1≦140° (2)
• where φ1 is measured as viewed from the side of the λ/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.