Thermal processor employing radiant heater

摘要

A thermal processor including a rotatable hollow drum including a drum core having an interior surface and an exterior surface, and a radiant heater positioned within an interior of the drum and configured to provide radiant energy to heat the drum, wherein at least one radiant energy absorption characteristic of the interior of the drum varies across its longitudinal width Wd so that selected areas of the interior of the drum absorb more radiant energy than other areas of the interior of the drum so as to compensate for non-uniform heat loss from the drum and to provide the exterior surface of the drum core at a desired temperature which is substantially uniform across the longitudinal width of the drum core.

主权项

1. A method of operating a thermal processor for thermally developing photothermographic film, comprising:
positioning a radiant heater within an interior of a rotating hollow drum, the radiant heat providing radiant energy to heat the hollow drum; and modifying radiant energy absorption characteristics of an interior surface of the hollow drum so that selected areas of the interior surface of the drum absorb more radiant energy than other areas of the interior surface of the drum in order to compensate for non-uniform heat loss from the hollow drum so that the exterior surface of the hollow drum has a temperature which is substantially uniform across a longitudinal width of the drum, wherein modifying the radiant energy absorption characteristics comprises grooving an interior surface of end portions of the hollow drum such that the interior surface of the end portions of the hollow drum have a greater surface area per unit length in a longitudinal direction of the hollow drum than the interior surface in a middle portion of the hollow drum.