We study imaging systems designed to assess the smile of laser diode bars (LDBs). The magnification matrix is derived from the required sampling period and the geometries of the LDBs and the charge-coupled device (CCD) array. These image-forming systems present in-plane pure translation invariance, but in the case of anamorphic ones, lack in-plane rotation invariance. It is shown that the smile parameters of the image of the LDB are linked with the smile parameters of the LDB by simple mathematical expressions. The spatial resolution of such optical systems is estimated at approximately $1\mathrm{\mu m}$ for a mean wavelength of $\lambda \approx 800\mathrm{nm}$ . Our results suggest that, with the current state-of-the-art, the formation of imaging methods for LDB smile assessment can be used to assess smile heights $\ge 1\mathrm{\mu m}$ .