Quantum logic gates are the basic building blocks of quantum computing system. Single qubit Pauli-X, Y and Z quantum gates are very much well known in quantum computing community. In this paper, we develop tri-state Pauli-X, Y and Z quantum gates using phase encoding technique of light. This phase encoding mechanism makes the implementation of those gates easier even with tri-state approach. As light is used for signal representation, one can exploit the parallelism in operation.