Acer X139WH. Projector brightness: 5000 ANSI lumens, Projection technology: DLP, Projector native resolution: WXGA (1200x800). Light source type: Lamp, Service life of light source: 6000 h, Service life of light source (economic mode): 10000 h. Focus: Manual, Focal length range: 21.85 - 24.00 mm, Aperture range (F-F): 2.41 - 2.53. Serial interface type: RS-232, HDMI connector type: Full-size, HDMI version: 1.4a. Noise level: 32 dB, Noise level (economic mode): 27 dB, Projection modes: Front, Rear