MEASUREMENTS OF THE TEMPERATURE DISTRIBUTION OF A SHADOW MASK IN A CATHODE-RAY TUBE BY USE OF A RADIATION THERMOMETER

This paper presents an experimental study of non-contact temperature m easurements for the shadow mask in a cathode-ray tube (CRT) by use of a radiation thermometer. As the demand for large and flat CRTs and hig h resolution increases, it becomes more important to design the shadow mask assembly precisely, even for the Invar shadow mask CRT that brin gs about a shift of the landing site of the order of a few micrometres . To do this, first of all knowledge about the temperature distributio n of the shadow mask is needed. However, up to now most researchers co uld not measure the temperature distribution of a shadow mask. We stud ied a method for measuring the temperature distribution of a shadow ma sk for a 17 '' CRT. Considering the energy and the wavelength passing through the face plate, we equipped the radiation thermometer with an indium antimonide (InSb) photo-sensor. Experiments using the thermocou ple were performed to validate the results of non-contact measurement. The results agree well with those of a non-contact method using an In Sb sensor.