Handheld projector

A handheld projector (also known as a pocket projector, mobile projector, pico projector or mini beamer) is technology that applies the use of an image projector in a handheld device. It is a response to the emergence/development of compact portable devices such as mobile phones, personal digital assistants, and digital cameras, which have sufficient storage capacity to handle presentation materials but little space to accommodate an attached display screen. Handheld projectors involve miniaturized hardware and software that can project digital images onto any nearby viewing surface.

The system comprises five main parts: the battery, the electronics, the laser or LED light sources, the combiner optic, and in some cases, scanning mirrors. First, the electronics system turns the image into an electronic signal. Next, the electronic signals drive laser or LED light sources with different colors and intensities down different paths. In the combiner optic, the different light paths are combined into one path, defining a palette of colors. Finally, in some technologies the mirrors copy the image pixel-by-pixel and can then project the image. Other optical systems do not use the "mirrors" technology, and are considered more robust. This entire mirror system is compacted into one very tiny chip. An important design characteristic of a handheld projector is the ability to project a clear image, regardless of the physical characteristics of the viewing surface.

Major advances in imaging technology have allowed the introduction of hand-held (pico) type video projectors. The concept was also introduced by Explay in 2003 to various consumer electronics players. Their solution was publicly announced through their relationship with Kopin in January 2005.

Insight Media market research has divided the leading players in this application into various categories:

Manufacturers have produced handheld projectors exhibiting high-resolution, good brightness, and low energy consumption in a slightly larger format than pico. However, most handheld LED projectors, as of December 2014, have been widely criticized for having insufficient brightness for everyday use in a normally lit room.

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