Light beam named ray, A. 

 - Videocassette (VHS)(ca. 25 min.) : sd., col., 1/2 in. 
<br/><br/> A lively animated film explaining the fundamentals, properties and physics of light, colour and optics. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Light#xStudy and teaching.