With the rising use of optical communication in different commercial as well as military systems, the issue of optical data security becomes eminent. There are two approaches for dealing with this need: using known encoding methods from electronic communication or developing optical encoding methods. In the first approach, the encoding may be done electronically before converting the information to an optical signal. However the ambition for all optical systems has derived setups for optically implementing these methods. In the second approach new optical encoding methods are developed in order to avoid the complexity of converting electrical methods into optical ones. Furthermore, optical encoding methods best utilize the built in properties of optical data transmission. We present a novel approach for designing a phase mask encoded by wavelength and illumination angles. Via simulations we demonstrate a high sensitivity to the decoding parameters.