2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/3423We use three strong lensing clusters to constrain the cosmological parameters Omega_m and Omega_lambda. Recent HST observations of galaxy clusters reveal a large number of multiple images, which are predicted to be at different redshifts. We showed in a previous work that if it is possible to measure spectroscopically the redshift of many multiple images then one can constrain (Omega_m,Omega_lambda) through ratios of angular diameter distances independently of any external assumptions. Using three strong lensing clusters, our combined results lead to tight constraints.2 pages, includes 4 figures, to appear in the proceedings of the Sesto 2001 International Workshop "Tracing Cosmic Evolution with Galaxy Clusters", July 2001, Sesto (Italy)Astrophysicstext