Negative dispersion dielectric multilayer mirrors have contributed significantly to the enhancement of the performance, compactness and reliability of femtosecond lasers. There are two alternative approaches that are widely investigated for dispersion compensation: chirped mirrors and Gires-Tournois mirrors. Chirped mirrors can exhibit a broad smooth high reflectance range if the layer thickness is superimposed a quasi-periodic modulation on a linear variation of the optical thickness of the layers. The performance of such chirped mirrors is calculated and the factors affecting the performance are discussed in detail. In such chirped mirrors, the performance is strongly affected by the expected bandwidth and modulation period of the optical thickness of the layers.