3. The burners
First of all, there is an additional optical encoder that needs to be added close to the spindle mechanism. For now, all manufacturers use a separate small optical encoder PCB, that needs to be wired with the main PCB, as you can see in the following picture. Clicking on the image will open a higher resolution picture.
There are also some modifications on the follower (sledge guiding rack). Manufacturers need to modify its shape and dimensions to reach CFZ at ID. Below, you can see the sledge guiding rack.
Of course, these modifications cannot be done in any drive in order to enable LightScribe. The drive itself must have enough power to perform LightScribe printing. As HP states, "with minimal hardware and firmware modifications, Lightscribe-licensed drives can burn labels on LightScribe media using the drive's existing laser. A high-speed interface coordinates drive capabilities to optimize labeling and imaging commands to facilitate burning. Drives are turned into combination label burners and data reader/writers via solutions that include:
- Laser focus: A novel focus strategy provides sufficient focus control for consistent, uniform imaging on the label surface
- Tracking control: Images are printed as concentric circular tracks, so precise tracking control is required. A tracking solution maintains constant track spacing, measured in microns, as the laser moves across the disc
- Low-speed spindle control: Accurate speed control is essential for pixel placement along a track as the disc rotates. A speed control solution achieves the required pixel placement accuracy
- Write channel: A high-speed hardware communications channel - distinct from that used for data writing - is used for labeling"