The design and construction of an apparatus to measure the optical birefringence of a liquid crystal is described. The instrument also includes temperature control and monitoring circuitry to allow for the measurement of the nematic-to-isotropic phase transition temperature. An important feature of this design is that the students are able to build the optical bench section of the instrument from a kit of parts supplied. The electronics instrumentation for the illuminator, photometer, and temperature controller functions are all low-cost designs using common components, yet provide more than adequate accuracy for the measurements required. The entire instrument cost is $430, an estimated cost reduction of approximately $3000 compared to the design previously proposed by Waclawik et al. This instrumentation is suitable for second or third-year undergraduate students in materials science or physical chemistry courses.