Alan Freedman -- The Computer Language Company - Computer Desktop Encyclopedia
Computer Desktop Encyclopedia
Longest-Running Tech Reference on the Planet

A CDE Definition

You'll love The Computer Desktop Encyclopedia (CDE) for Tech Term of the Day (TTOD)


Holographic Versatile Disc

See HVD.


(1) (High Voltage Differential) See SCSI and differential signaling.

(2) (Holographic Versatile Disc) A high-capacity optical disc from the HVD Forum ( that combines single beam holographic storage and DVD technologies to provide cartridge capacities reaching 1TB and beyond. Formed in 2005 as the HVD Alliance, the first HVD standards were released in 2007 for 100GB read-only (ECMA-378) and 200GB recordable (ECMA-377) formats.

HVD uses the conventional CD/DVD pit layer for addressing the disc, on top of which is the holographic recording layer. A red laser reads the addresses, while a green or blue laser reads and writes the holograms.

Single Beam Holography
Throughout the history of holographic storage research, two separate laser beams have been used to write the holograms at the intersecting point. Using Optware's Collinear Holography, HVD combines the two lasers into one lens, which reduces the size and cost of the mechanism. See holographic storage.

Layers in an HVD Disc

Personal Use Only

Before/After Your Search Term
Hollerith cardHoly Grail
Hollerith machineHoly Optochip
Hollywiredholy war
hologram storagehome app
holographichome automation hub
holographic data storageHome Basic
holographic googleshome brew
holographic storagehome broadband network

Terms By Topic
Click any of the following categories for a list of fundamental terms.
Computer Words You Gotta KnowSystem design
Job categoriesUnix/Linux
Interesting stuffPersonal computers
InternetIndustrial Automation/Process Control
Communications & networkingAssociations/Standards organizations
HistoryDesktop publishing
ProgrammingHealthcare IT
System design