Fix HP X22 LED Monitor Smudges / Shadow / Clouding / Black Spots

How to remove dirt from the Light Guide Panel of an HP x22 LED screen.

Start in the middle on the inside of the bezel and pull it gently outward with your fingers to unhinge the clips.

• Disconnect the LCD signal cable; press the metal latches on both sides while pulling the cable down.
• Disconnect the flat cable that controls the LEDs; pull the blue tab upward gently shifting it left to right and back.
• Remove 4 screws in the 4 corners of the backpanel
• Peel back the covering of the circuit board.
• Remove the front bezel holding the light guide panel in place.

I cleaned the acrylic glass light guide plate with dishwashing soap mixed with methylated spirits. I think meths can dissolve the reflective dots so this is not for the faint of heart. Afterwards I rinsed it off with hot water.

The cleaning reduced the smudges considerably but they are still visible.

There were also dirt / water stains behind the white reflection screen. Which is very sensitive to scratching.

Putting everything back together again dustfree can be difficult with tiny dust particles being attracted to the statically charged plastics. A silicone sticky roller to remove the dust might make things easier.

The display was manufactured May 2010 and I bought it from an online secondhand goods store.