Measuring theγγcoupling of the Higgs boson at linear colliders

Observing the production of the Higgs particle in the $\gamma \gamma$ mode of a linear $e^{+}{e}^{-}$ collider allows for the measurement of the $H\gamma \gamma$ coupling. We point out that for the intermediate Higgs mass range this measurement is considerably more challenging than previously believed. The $b\overline{b}$ signature receives a large background from the production of heavy quark pairs by resolved photons. We quantify the experimental requirements needed to make a meaningful measurement in the presence of this background.