摘要 |
<p>This invention provides a method of observing the interior of a furnace by viewing, at a remote location, the image depicted by a pinhole camera sited in or within the furnace housing. The image may be real and viewed directly or via a reflective or fibre optic transmission system, or alternatively a video camera may be employed, in this instance the 'screen' of the camera may be constituted by light responsive elements, e.g. charge coupled devices. The camera may typically be sited in the furnace wall or roof and a pressurised blast of air or an inert gas, e.g. nitrogen or argon, may be employed for maintaining the integrity of the pinhole.</p> |