Q.
DLP projectors are promoted as being highly resistant to dust and debris. Why is this?

A.
Projectors generally rely on the intake and circulation of air to cool the heat generated by the lamp, and because of this dust and debris can accumulate on the projector’s internal components.
The DLP projection system is simpler in construction, using mirrors to reflect light, and unlike other projection systems DLP devices can be cooled on the side opposite the light receiving surface. This allows the device to be hermetically sealed for outstanding dust resistance.

Q.
If the DLP system is dust-resistant, why is a dust filter necessary?

A.
Dust and debris circulating in the air need to be kept from accumulating on the lamp and other optical parts in order to maintain image quality. While the single-chip construction of the DLP device allows it to be hermetically sealed, additional dust-resistance measures are taken to protect optical components and improve overall dust resistance even further.

Q.
How effective is the dust filtering system?

A.
The filtering system traps up to 85 percent of particles 1.6μm or larger in size. Mould particles and spores, for example, are generally around 3.0μm in size, house dust and pollen range from 10μm to 100μm, and airborne sand from 0.5μm to 5μm.
In dust-prone locations such as offices and factories, or in places where many people congregate, the dust-resistant function is especially effective when the projector is permanently mounted to the ceiling. It should be noted however, that the filtering system is less effective in the case of cigarette smoke, which has a particularly small particle size.

Q.
Can the lamp be replaced in a ceiling-mounted projector without detaching it from the mounting?

A.
The PD121X projector lamp is replaced via the base of the unit (the side nearest the ceiling); for this reason, the unit must be detached from the ceiling mount when replacing the lamp.