Provided is a test apparatus comprising a plurality of pattern output sections. The switch is preferably formed integrally with the columnar nano-structure. If the current levels do exceed the predetermined limit, the invention performs an optimization process. These two types of compressors are susceptible to undesirable unpowered reverse rotation when compressed refrigerant re-expands through the compression elements from the compressor discharge into the compressor suction. The illumination light source is arranged at a position where a mirror reflection region that mirror reflects light entering from the illumination light source to the sensor section is outside a region of the subject and the reference chart section. The invention further provides a method of preparing such a polishing disk and a method of polishing a substrate with such a polishing disk.