Use this guide to remove the air filter from your Optoma HD20.
Step 1 Cover
Twist focal cap clockwise until it is fully extended.
Remove focal cap by pulling it straight out.
Use a Phillips #1 screwdriver to remove the three 7.5mm screws on the bottom of the device.
Use a plastic opening tool to gently pry the top cover off of the device.
It is easiest to pry off the cover from the back side just above the HDMI ports.
When removing the cover, be cautious of the ribbon connecting the top buttons to the main circuit board. The ribbon must be disconnected before proceeding.
Remove the ribbon by disconnecting it from the main circuit board.
Lift up the clip holding it down and pull the ribbon out.
Step 5 Air Filter
Carefully peel off each air filter from the device
Pull up on the air filter to remove it.