Electrical strain-gages are the most widely used devices by industrial and academic laboratories in order to monitor strain and stress fields in mechanical parts where their integrity has to be evaluated [1]. Even though portability, robustness, accuracy and range of measurement of strain gages have been firmly established, their installation is time-consuming and requires skills and aptitudes of a quite well trained technician. Optical configurations for measuring in-plane displacements with DSPI are usually based on the two-beam arrangement first described by Leendertz in 1970 [2]. To simultaneously compute both in-plane components [2], DSPI systems based on polarization discrimination methods have been developed [3], however with some practical drawbacks [4]. Albertazzi et al. [5] have managed to deal with these limitations by means of the development of a novel double illumination DSPI system which measures radial in-plane displacement fields. In this work, the interferometer was combined with a pneumatic turbine drill to obtain a portable device for determining residual stresses by applying the hole-drilling technique. This device used a high quality conical mirror which makes it quite expensive, and requires a wavelength stabilized laser. This paper reports on the application of a diffractive optical element (DOE) for generating double illumination and radial in-plane sensitivity. It is first demonstrated that the DOE has allowed development of an achromatic DSPI device, whose sensitivity is independent of the wavelength of the light source. It is sensitive only to the period of the grating of the DOE. Experimental results carried out in the laboratory by using an experimental setup with red and green light sources are presented. Furthermore, the paper briefly reports on results of residual stresses measurement in pipelines.