Head mounted display and viewing system using a remote retro-reflector and method of displaying and viewing an image

An optical device for presenting for viewing at a viewing location images from an image source, comprising:

• focusing means for focusing light from a source to form a real image,
• retro-reflector means for receiving incident light from said focusing means and reflecting light along an at least partly conjugate optical path relative to the incident light thereon toward a viewing location, and
• beamsplitter means for reflecting and transmitting light,
• said beamsplitter means being in the optical path between said focusing means and said retro-reflector means and being operative at least one of (a) to reflect light toward said retro-reflector means and to transmit light from said retro-reflector means for viewing and (b) to transmit light to said retro-reflector means and to reflect light from said retro-reflector means for viewing,
• said retro-reflector means and said beamsplitter means being cooperatively related in effect to cause the viewing location where the image is presented to appear, relative to the image source, at the location of said focusing means,
• said retro-reflector means comprising two retro-reflectors, one being positioned to receive light reflected by said beamsplitter means and one being positioned to receive light transmitted by said beamsplitter means, and further comprising a lens in the light path between said beamsplitter means and one of the retro-reflectors to focus light from said one retro-reflector for viewing at the viewing location in overlapping coincidence with light from the other retro-reflector.

An optical system, comprising

• a retro-reflector for receiving incident light and reflecting light as reflected light,
• wherein at least part of the paths of the incident light and the reflected light are a conjugate light path,
• a beamsplitter in the conjugate light path for directing light to said retro-reflector as such incident light to form a real image,
• said beamsplitter also directing reflected light from said retro-reflector to a viewing location, and
• focusing means in the path of light to or from said beam splitter for causing the image viewed at the viewing location to appear at a comfortable viewing distance.

An optical system, comprising

• a retro-reflector for receiving incident light and reflecting light as reflected light,
• wherein at least part of the paths of the incident light and the reflected light are a conjugate light path,
• a beamsplitter in the conjugate light path for directing light to said retro-reflector as such incident light to form a real image,
• said beamsplitter also directing reflected light from said retro-reflector to a viewing location, and
• a further retro-reflector for reflecting back to said beamsplitter light that is directed by said beamsplitter in a direction that is not toward said retro-reflector, and further comprising a lens to focus light from said further retro-reflector for coincidence at the viewing location with light reflected by said retro-reflector.