3D Technologies

View a comparison of Stereoscopic vs. Volumetric technologies.

Stereoscopic

• Overview
  • Caters to our binocular vision by presenting a left eye image that is segregated from the right eye image using an optical, physical or temporal modulation (or some combination)
  • The 3D image does not change with the viewer’s position relative to the display (for a given image)
• Anaglyph
  • Stereo paired images are colored with red/blue or red/green tint for the left eye/right eye image
  • Stereo separation is perceived when viewed with the glasses incorporating eyepieces with the same tint
  • Not employed widely for professional use
• CRT Based
  • Frame sequential stereo (2x the typical refresh rate):
  • LC Shutter Glasses with synchronization to the CRT
  • LC Shutter switches polarization of the CRT output to circularly polarized glasses
  • Response time limitations have prevented using AMLCD monitors to date
• HMD
  • Stereoscopic 3D HMDs make use of a pair of miniature displays mounted near-to-eye and segregated to present respective left eye/right eye images
  • Display technologies: AMOLED, AMLCD, AMEL
• Autostereo
  • Lenticular/Parallax
    • Image processing can be used to create additional “views” or domains that increase the viewing angle
    • Uses AMLCDs with an added optical element to create a dual view (left eye/right eye) presentation of the image on the screen
    • A optimum viewing space is created
  • Other
• Optically Fused
• Dual Panel
  • A pair of laminated AMLCDs is used
  • One panel controls pixel intensity, the other polarization distribution
  • Custom algorithm used for driving the two panels
• Projection
  • Single projector
    • Projection at 2x typical refresh rate
    • Passive polarizing glasses provide stereo contrast with a fast-switching shutter on the output of the projector
    • Requires a non-polarizing screen (typically silvered)
    • No alignment issues
  • Dual projector
    • Projection at standard refresh rate through crossed polarizers
    • Passive polarizing glasses provide stereo contrast
    • Requires a non-polarizing screen (typically silvered)
    • Alignment can be an issue
    • Same technique used in film-based 3D cinema
    • Projector alignment can be an issue

Volumetric

• Overview
  • Provides real depth cues due to presentation (usually projection) of the image onto a 3D surface
  • The 3D image changes with the viewer’s position relative to the display
  • Volumetric displays are extremely expensive
  • The image they show is not solid; you can see through lines and surfaces that are supposed to be opaque
  • Volumetric displays require a great deal of processing to show one frame
• Swept Volume
  • Provides 360° viewing angle without glasses, allows multiple simultaneous viewers
• Holographic
  • Autostereo 3D display using a holographic screen and multiple image sources and to produce unique viewer-dependent images
• Laser