We report the results of our studies on the optical and thermal properties of the mixture of Sodium Lauryl Sulfate (SLS) and Dodecyl trymethyl ammonium bromide + Ethylene glycol (DTAB+EG) exhibits very interesting induced thermotropic smectic phases such as smectic-A, smectic-D, smectic-B, and smectic-E phases, sequentially when the specimen is cooled from its isotropic liquid phase. Different liquid crystalline phases observed in the mixture were studied using DSC, X-ray, and Optical microscopic techniques. The temperature variation of optical anisotropy has also been discussed. Helfrich potential and elastic moduli have been estimated in the smectic phase using Helfrich model.