試作せる二,三のシャッター検査器について

抄録

Four types of camera shutter tester are described in this paper. The first one is the type of Braun tube oscilloscope and its screen is long persistence phospher P₇. The time mark is obtained by succession of high speed switching of the spot and the observed pattern appears as two-element Braun tube. This switching is forced by accurate frequency of 12 kinds from 10 kc to 10c/s which is syncronized by 100kc crystal. The second and third ones are condenser chronograph type and can measure shutter speed and time lag. The sensitivity of this meter can be checked by a watch and a simple supplementary adapter which consists of pair of a capacitance and a micro-switch. The fourth one is a dynamical resistance meter, and the syncrocontact resistance can be measured under actual conditions. This meter consists of a non-inductive resistance, a 4000μF capacitance and a gate circuit. The gated pulse, height is measufed by pulse lengthening circuit. The gate time is chosen to 2.5ms for M contact and 1ms for X contact. This values are resonable from shutter mechanics and flash bulb characteristics, and this is very important for actual shutter properties.