Sharp CD-PC651 No disc

If there is no beam from the lens, then the laser is either dead or not being turned on.

But, the laser in a CD player is 780 nm, near IR, and close to invisible. It's not bright like a DVD player's laser. Just a faint red dot in the when viewed from the side.

--- sam | Sci.Electronics.Repair FAQ:

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The laser in a CD operates at near-infrared, so emits little visible light. With the lens area shaded, and looking across the top of it at an oblique angle, you should just be able to see a little 'sparkling' red light in there, whilst the focus search is taking place. If you do see the light, and the lens is clean, but the disc either never spins up, or spins endlessly without ever reading the TOC, or stops with a "NO DISC" message, then it's very likely that the laser is faulty. The only 'real' test for a defective laser is to try a replacement. If you cannot see any red light at all in the lens, then it's not burning, and the commonest causes of that are either a defective laser diode within the optical block, or a bad cable to the optical block. The flat white flexiprint type has a habit of fracturing across one or more tracks, right by the blue reinforcing strip at one end or the other. Types using conventional wires tend to fracture inside the wire's plastic sleeve, close to where it is crimped into the connector pin in the plug body.

Although the output power of a CD laser is in the 'eye safe' category, I still would not recommend looking straight down into the lens ...

Arfa