A direct-reading photo-electric photometer for the commercial measurement of incandescent electric lamps

This paper describes the practical difficulties experienced and overcome in the development and construction of a type of photo-electric photometer suitable for measuring incandescent electric lamps of the vacuum and gas-filled 10-watt to 100-watt types. The apparatus is capable of measuring lamps at commercial speeds under continuous service conditions. The construction is simple and uses mainly standard component parts.