The manufacturer Acer further enhances its range of mobile projector with K138ST. This model shows a brightness of 800 lumens in a format of only 240 x 147 x 59 mm to 750 grams. Exploiting the Texas Instruments DLP technology, this model is still limited to a definition of 1280 x 800 pixels. Backlighting is provided by LED with a lifespan of 20,000 hours. Acer announces contrast 100,000: 1 and a noise of 33 dB (A). The Acer compact projector offers a short focal mode that displays a 100-inch image (2.54 meters) with a decline of only 1.7 meters.  The Acer K138ST also carries two speakers