The disclosure relates to a method and apparatus for providing switching optical filter. Imaginary central axes of the outflow ports directed in a flow direction herein enclose a mutual angle in order to intersect each other at an intersection. The client executes the page token refresh program in response to a request to post the contents of the form to the server computer. The pump module is removably contained in the controller module. A heat radiation plate through which heat generated from the thermal head during printing can escape is arranged between the thermal head and the head supporting portion, and the thermal head can be adjustably curved toward the platen roller via the heat radiation plate by an adjusting member arranged in the head supporting portion. One or more anneal processes may be implemented at various points in the processing to eliminate the crystallized W2N layer and weaken the SiNx layer.