Sprockets are used in the film transport mechanisms of movie projectors and movie cameras. It can stream on TVs, projectors, and media players. Peak lumens is a measure of light output normally used with CRT video projectors. Examples include shader lamps, mobile projectors, virtual tables, and smart projectors. Fresnel lenses are also used as collimators in overhead projectors. Not included are IMAX venues with solely 2K resolution digital xenon projectors. Examples include small high-resolution displays such as those found in projectors or viewfinders. Mass production of laser diodes for commercial devices like laser projectors have driven down prices. Linear polarization was likewise used with consumer level stereo projectors. These include slide projectors, PowerPoint presentations, overhead projectors, and computer projectors. Lenses with finer steps serve as condensers in overhead projectors. Computer projectors are the most technologically advanced projectors. Most planetariums used Apple IIs to control their projectors and other equipment. This is the native resolution for DCI 4K digital projectors and displays. This is the native resolution for DCI-compliant 2K digital projectors and displays.