Sensing contamination level in an optical storage device

An apparatus for monitoring a buildup of contamination on optical elements in an optical recording device, comprising:

• means for generating a tracking error signal indicative of track crossings on an optical disk;
• means for determining a gain value of the tracking error signal;
• means for comparing the gain value of the tracking error signal with a predetermined value;
• means for generating an alert signal if the gain value exceeds the predetermined value, the alert signal indicative of an excessive buildup of contamination on optical elements in the optical recording device;
• and
• means for cleaning at least a portion of said optical elements in response to the alert signal.

A method for monitoring a buildup of contamination on optical elements in an optical recording device, comprising the steps:

• mounting an unrecorded optical disk in an optical recording device;
• measuring an initial gain of the tracking error signal;
• storing the initial gain of the tracking error signal in a memory device as a base gain value;
• initiating a seek operation on the optical disk mounted in the optical recording device;
• generating a tracking error signal indicative of track crossings;
• determining a gain value of the tracking error signal;
• comparing the determined gain value with the stored base gain value;
• generating an alert signal if the determined gain value exceeds a predetermined value relative to the base gain value, the alert signal indicative of an excessive buildup of contamination on optical elements in the optical recording device;
• and
• cleaning optical elements in the optical recording device in response to the alert signal.

An automated optical storage and retrieval system, comprising:

• an optical disk drive;
• a plurality of addressable storage cells for holding a plurality of optical recording disks;
• an accessor for transporting a selected one of the plurality of optical recording disks between a respective storage cell and said drive;
• and
• a library controller interconnected with a host device, said drive and said accessor;
• said drive having:
• a drive motor for rotating an optical disk mounted thereto, the disk having a plurality of tracks;
• an optical system having a light source for projecting a light beam, an optical head having optical elements for focusing the light beam on a surface of the disk and a sensor for detecting light reflected from the surface;
• an actuator for transporting said optical head in a radial direction across the surface of the disk;
• and
• a tracking error signal generator responsive to said sensor for generating a tracking error signal;
• and said library controller having:
• means for measuring a gain value of
• the tracking error signal;
• means for comparing a measured gain value of the tracking error signal with a predetermined base gain value;
• means for generating an alert signal if the gain value of the tracking error signal exceeds a predetermined relative amount of the base gain value, the alert signal indicative of an excessive buildup of contamination on the optical elements in the optical disk drive;
• and
• means for cleaning at least a portion of the optical elements in response to the alert signal.