AC-3 (Audio Coder 3): Dolby Digital (also ATSC A / 52 and AC-3) is a multichannel audio system from Dolby corporation and is almost exclusively available to NTSC discs. In Germany there were only two laserdiscs with AC-3 sound (True Lies and The Long Kiss Goodnight).
Box set: A box set (also boxed set) is a compilation of several films or discs that will be sold in a special packaging and is intended primarily for collectors.
CAV: CAV (Constant Angular Velocity) allowed slow motion and still images with optimum quality with a particular rotational speed, the playing time is limited to 30 minutes (NTSC) or 36 min (PAL) on each side.
CLV: To accommodate feature films on the both sides playable medium, the CLV method was developed. CLV (Constant Linear Velocity or Extended Play) allows for the same quality but 60 min (NTSC) or 64 min (PAL) per side.
Dolby Digital / Surround: A sound format from Dolby corporation. Due to the required "analog" sound track the "Dolby Digital Surround" was only possible on discs that were recorded in the NTSC format.
Director's Cut: The Director's Cut is a special version of a feature film, with which the film director displays his personal artistic intention.
Laser rot: Because of production errors in the reflective layer of the optical disk, there may be an appearance of "laser rot". This is a chemical process that leads to oxidation between the layers. Not all laser discs are affected and a rule of thumb says that which disc is not affected until now, will probably not suffer from laser rot in the future. Laser rot is very visible in the picture and sound, in severe cases (but not always) there is a dark discoloration of the disc itself and the rot is instantly recognizable this way.
Letterbox: Letterbox refers to a process in the image processing and video equipment where black borders were added to the picture. The aim was to adjust the aspect ratio of an image, eg. to fit the aspect ratio of a screen.
NTSC: NTSC denotes the analog television system which was used in the US, Canada and Japan, and was later replaced by the digital television standard ATSC.
OBI: OBI's are small paper strips that were affixed with Japanese releases, usually on the right edge of the envelope and that showed details and features of the film. OBI's can also appear as a paper corner or as a sticker on the jacket and a missing OBI can decrease the value for a serious collector.
PAL: PAL is a TV system that is used primarily in Europe but also in Australia and many countries in Africa, Asia and South America.
Pan and Scan: Pan & scan is a process which attempts to display part of a wide-screen cinema image on a 4: 3 or 16: 9 TV screen. With pan & scan the audience is given the opportunity to select a pivotable image section of the (not fully viewable) widescreen image to be displayed on the screen.
THX: THX is a commercial quality seal of George Lucas' group of companies. A common misconception is that THX is a sound system, similar to Dolby Surround, SDDS or DTS.
Widescreen: Widescreen formats are formats for the movie (usually 35 mm) which experienced their initial widespread use in the 1950s. Widescreen refers to all image formats that are wider than the so-called normal or Academy ratio (1.33: 1 or 1.37: 1).