Abstract: A glass electrode is capable of measuring a cation concentration of a test solution. The glass electrode includes a flat sensitive glass body sensitive to ions, a base body formed of a glass tube housing an internal solution, and a fixation layer used to sealingly attach the sensitive glass body to an end surface of the base body. A resistance value of the fixation layer is equal to or higher than a resistance value of the sensitive glass body. A liquid property measurement device is equipped with the glass electrode.

Abstract: A glass electrode is capable of measuring a cation concentration of a test solution. The glass electrode includes a flat sensitive glass body sensitive to ions, a base body formed of a glass tube housing an internal solution, and a fixation layer used to sealingly attach the sensitive glass body to an end surface of the base body. A resistance value of the fixation layer is equal to or higher than a resistance value of the sensitive glass body. A liquid property measurement device is equipped with the glass electrode.

Abstract: Certain embodiments of the present invention provide a refractometer including: a housing having an immersion portion, the immersion portion having an opening; a light source for emitting a light; a light sensor for converting a received light into an electrical signal; a prism including faces, including: a first face proximal to the light source and the light sensor; a second face, at least a portion of the second face configured for contacting a sample liquid through the opening, and for forming an interface between the second face and the sample liquid; and a third face, wherein the light travels by: being directed towards the second face; being reflected at least in part by the interface towards the third face; and being reflected at least in part by the third face towards the light sensor. In an embodiment, the refractometer further includes a control portion for receiving the electrical signal, and for determining a refractive index of the sample liquid based at least in part on the electrical signal.

Abstract: Certain embodiments of the present invention provide a refractometer including: a housing having an immersion portion, the immersion portion having an opening; a light source for emitting a light; a light sensor for converting a received light into an electrical signal; a prism including faces, including: a first face proximal to the light source and the light sensor; a second face, at least a portion of the second face configured for contacting a sample liquid through the opening, and for forming an interface between the second face and the sample liquid; and a third face, wherein the light travels by: being directed towards the second face; being reflected at least in part by the interface towards the third face; and being reflected at least in part by the third face towards the light sensor. In an embodiment, the refractometer further includes a control portion for receiving the electrical signal, and for determining a refractive index of the sample liquid based at least in part on the electrical signal.