Cartridge containing first-surface storage medium

Abstract

A user-removable optical data storage system is provided. A rotatable first-surface medium is enveloped in a cartridge. The cartridge provides relatively large data capacity such as about 0.25 Gbytes or more despite a relatively small size such as about 35 mm×35 mm×3 mm. Preferably the cartridge substantially seals the data surfaces of the medium when the cartridge is withdrawn from a drive and at least a portion of one surface is automatically exposed to the objective of an optics arm when said cartridge is inserted in the drive. Tracking involves rotating an optic arm about an axis parallel to the disk rotation axis. Focus can involve pivoting the arm about an axis parallel to the disk surface.

What is claimed is:  
     
         1 . An optical disc within a cartridge comprising: 
 a first-surface optical disk including: 
 a single substrate having first and second principal surfaces; and  
 a recording layer overlying the first principal surface of the substrate; the first-side optical data storage disk being distinguished from second-surface optical disks by the absence of an additional substrate overlaying the recording layer having a thickness sufficient to defocus dust particles with respect to a laser beam reading the recording layer without passing through the single substrate;  
   the optical disk within a cartridge further comprising a cartridge body, with said first-surface optical disk positioned therein.    
     
     
         2 . The optical disk within a cartridge as claimed in  claim 1  wherein said cartridge body includes at least an arcuate window region covered by a plate which is transparent at a first wavelength.  
     
     
         3 . The optical disk within a cartridge as claimed in  claim 1  wherein said cartridge body is configurable between a first configuration substantially enclosing the first-surface optical disk and a second configuration exposing a portion of the first-surface optical disk for reading and writing on the first-surface optical disk as the first-surface optical disk is rotated.  
     
     
         4 . The optical disk within a cartridge as in  claim 3  wherein said cartridge comprises a window for exposing a portion of the first-surface optical disk and a first shutter movable from a first position wherein said cartridge is in said first configuration to a second position when said cartridge is in said second configuration.  
     
     
         5 . The optical disk within a cartridge as claimed in  claim 4  wherein said window has a transverse extent sufficient to accommodate at least partial insertion of an objective end of an optics arm through said window.  
     
     
         6 . The optical disk within a cartridge as claimed in  claim 1  further comprising a plurality of recesses formed in an edge surface of said cartridge for encoding characteristics of said medium.  
     
     
         7 . The optical disk within a cartridge of  claim 1 , wherein the recording layer of the first-surface optical disk defines a surface of the first-surface optical disk.  
     
     
         8 . The optical disk within a cartridge of  claim 1 , wherein the first-surface optical disk further comprises a relatively thin film overlaying the recording layer and defining a surface of the first-surface optical disk.  
     
     
         9 . The optical disk within a cartridge of  claim 8 , wherein the relatively thin film is a few molecules thick.