Microscope and magnification changer

A stereo microscope for stereoscopically studying an object, comprising:

• two separate light paths for two separate beams of light from the object;
• each said light path being defined by:
• a respective first reflective surface positioned and directed so as to intercept a respective one of the two separate beams of light;
• second reflecting surface means spaced from said first reflective surfaces;
• said second reflecting surface means being shaped and oriented to have the separated beams of light reflected to different locations on said second reflecting surface means by said first reflecting surfaces;
• said second reflected surface means also being shaped and oriented such that the two beams of light reflecting therefrom are disposed along substantially parallel axis;
• a respective magnification means and eyepiece in each said light path and positioned to intercept and receive a respective beam of light reflected from said second reflecting surface means;
• and
• a portion of each light path including, in series, a means for converging light leaving said second reflective surface means, and a magnification changer positioned to receive light converged by said converging means, said magnification changer comprising a converging lens, a diverging lens spaced along the optical axis thereof, means for rotating said lenses about a fixed point so that a converging light beam is initially incident upon either of said lenses or passes directly through the changer without impinging upon said lenses, thereby permitting a change of magnification to be effected between the three positions.