| 摘要 |
An absorptiometer in which a lamp source is arranged to direct radiation onto a radiation-sensitive device, means being provided for measuring an electrical output from the device and thereby deriving a measure of the optical density of a sample when located in the path between the source and the device, wherein for initial setting purposes, when a standard sample is located in the said path, means are provided for automatically varying the energization of the lamp source until the output of the radiation-sensitive device is set to a pre-determined value, and wherein, for subsequent measurement purposes, means are provided for maintaining the energization of the lamp source at the previously set value.
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