A substrate processing method which is capable of enhancing productivity in manufacturing product substrates. Therefore, since the telescopic gear base 6 and the telescopic gear member 8 intermesh gradually to slide, the tooth 6a and the tooth 8s readily intermesh during slide ). The intermediate cladding has a radius r2 and a positive refractive index difference \u0394n2 with the optical cladding, wherein \u0394n2 is less than \u0394n1. The adapter device has contact elements for touch contact with the test contacts.