Abstract An illuminating lamp for use in dentistry or medical clinic which provides for varying both the intensity of light output and the size of the illuminated area while maintaining a substantially constant color temperature. In this illuminating lamp, a light source consisting of a high intensity halogen bulb positioned horizontally at the inner focus of an ellipsoidal reflector projects through the aperture of a radiation reflecting disc; the light beam then converges at the external conjugating focus before reaching an optical zoom unit consisting of a heat absorbing filter positioned between one fixed and one movable lens. The beam intensity and its projected illumination area are manipulated with the zoom mechanism while the light beam spectral color temperature is controlled by the characteristics of a heat absorbing filter in conjunction with a spectral correction coating on the backside of the front covering glass. In addition, a special electrical circuit has been provided to eliminate the "cold-shock" to the filament of the halogen bulb in order to prolong its service life, along with an surge interruptor for the on-off switch in order to eliminate the possibility of a fire hazard throughout the electrical power system.
A zoom operating lamp useful for illuminating the oral cavity during dental and medical surgery, said lamp combination comprising: a lamp providing a light source having a uniform beam of light; an ellipsoidal reflector having an inner focus and an outer focus, wherein said lamp is positioned at said inner focus thereof; an iris positioned at the outer focus of said ellipsoidal reflector; a movable biconvex lens; and a fixed biconvex lens, said lenses being positioned on the side of said iris opposite said lamp and said reflector which together form a zoom-lens system.
Claim 2
Dependent Claim
94 words
A zoom operating lamp useful for illuminating the oral cavity during dental and medical surgery, said lamp combination comprising: a lamp providing a light source having a uniform beam of light; an ellipsoidal reflector having an inner focus and an outer focus, wherein said lamp is positioned at said inner focus thereof; an iris positioned at the outer focus of said ellipsoidal reflector; a movable biconvex lens; and a fixed biconvex lens, said lenses being positioned on the side of said iris opposite said lamp and said reflector which together form a zoom-lens system.
Claim 3
Dependent Claim
26 words
A zoom operating lamp as recited in claim 1, wherein there is included a heat-absorbing filter positioned adjacent said movable lens so as to move therewith.
Claim 4
Dependent Claim
22 words
A zoom operating lamp as recited in claim 2, wherein there is included a second heat-absorbing filter positioned adjacent said fixed lens.
Claim 5
Dependent Claim
22 words
A zoom operating lamp as recited in claim 3, including means for movably mounting said movable lens and its associated heat-absorbing filter.