A {gamma}-{gamma} collider has long been considered an option for a Higgs Factory. Such photon colliders usually rely on Compton back-scattering for generating high energy {gamma} photons and further Higgs bosons through {gamma}-{gamma} collisions. The presently existing proposals or design concepts all have chosen a very thick laser target (i.e., high laser photon intensity) for Compton scatterings. In this paper, we present a new design concept of a {gamma}-{gamma} collider utilizing a thin laser target (i.e., relatively low photon density), thus leading to a low electron to {gamma} photon conversion rate. This new concept eliminates most useless and harmful soft {gamma} photons from multiple Compton scattering so the detector background is improved. It also greatly relaxes the requirement of the high peak power of the laser, a significant technical challenge. A high luminosity for such a {gamma}-{gamma} collider can be achieved through an increase of the bunch repetition rate and current of the driven electron beam. Further, a multi-pass recirculating linac could greatly reduce the linac cost and energy recovery is required to reduce the needed RF power.
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