G02B15/00—Optical objectives with means for varying the magnification
G02B15/02—Optical objectives with means for varying the magnification by changing, adding, or subtracting a part of the objective, e.g. convertible objective
Systeme optique a reflexions pouvant etre adapte a l'appareil photographique, camera ou television permettant d'obtenir la reduction et la reproduction d'un espace avec perception du relief