Vacuum insulating chamber including waveguides separated by an air gap and including two planar reflectors for controlling radiation power from the air gap

A vacuum insulating chamber, the chamber comprising:

• a housing whose inside is maintained to be in a vacuum;
• an airtight component to maintain the housing in the vacuum,
• a heat insulating transmission line capable of transmitting and receiving signals between equipment and a circuit outside the housing, the equipment being housed inside the housing, the heat insulating transmission line including:
• a first waveguide with a first aperture end, the first waveguide mounted outside the housing;
• a second waveguide with a second aperture end, the second waveguide mounted inside the housing and arranged coaxially with the first waveguide, the second aperture end facing the first aperture end;
• an air gap between the first aperture end and the second aperture end;
• and
• a reflector provided outside the air gap, the reflector including two planar reflectors, the two planar reflectors facing each other across the air gap and spaced apart and thereby isolated from the first and second waveguides, the reflector suppressing power radiation from the air gap and being longer than a length of the air gap in a longitudinal direction of the first waveguide, wherein
• the two planar reflectors are substantially parallel to respective virtual planes including respective long sides of the first and second ends, the virtual planes each intersecting an inner wall of the first aperture end and an inner wall of the second aperture end;
• and
• a distance between each virtual plane and the respective reflector is not less than N×λ/2−0.05λ and not more than N×λ/2+0.2λ (N is a positive integer), provided that λ is a mean frequency of a signal transmitting through the heat insulating transmission line.