Hand held transparency projector with simple advance mechanism

A hand-held projector for projecting images from a film having perforations along an edge thereof comprising:

• a housing;
• a projection aperture in one end of the housing through which such images are projected and defining an optical axis therein;
• a light source carried within the housing and disposed along the optical axis;
• a film cartridge containing an endless loop of the film therein and having a front wall with a cartridge aperture defined therein;
• the film cartridge having a guide means for guiding a viewing portion of the film in an aligned, parallel relation to the cartridge aperture;
• push means disposed between the light source and projection aperture movable for advancing the film in steps one frame at a time;
• the push means including means defining a push means aperture in line with the optical axis;
• and
• an advancing claw carried by the push means which upon a film advancing stroke of the push means engages the perforations of the film to advance such film and upon a positioning stroke of the push means avoids engagement with such perforations;
• the housing including means defining a cartridge recess adapted to receive the film cartridge and means for removably securing the film cartridge within the cartridge recess such that the light source, cartridge aperture, viewing portion of the film and push means aperture are all in alignment with and perpendicular to the optical axis to enable the image exposed by such viewing portion to be projected through the projection aperture;
• the advancing claw of the push means extending into the film cartridge through the cartridge aperture to engage the perforations of the film when the cartridge is secured within the cartridge recess.