The invention relates to a durable and reliable miniature liquid junction reference electrode for use with at least one electrode for measuring certain characteristics of a fluid sample such as blood or other body fluid. The characters are stored in memory in association with a standard alphanumeric character set such as an ASCII character set. The main circuit comprises a compressor, a condenser unit, an expansion device, an evaporator unit, connecting piping and appropriate refrigeration control. A first controlling unit starts a first operation relating to an imaging process in a case that a first time passes from a point of receiving the response signal by the response signal receiving unit. Correction data for a selected phase point is calculated based on the measured phase and amplitude. An exemplary transparent composite comprises a glass reinforced thermosetting polymer composite layer sandwiched between glass layers.