| This paper describes a handheld instrument for noninvasive detection of breast cancer based on a broadband optical spectroscopy technique called FDPM, for frequency domain photon migration. It performs broadband modulation on the intensity of near-infrared laser diodes and derives the scattering and absorption coefficients of the bulk tissue from phase and amplitude data measurements. This Handheld Breast Scanner (HBS) has been designed and developed for several versions with different schematics from homodyne to full heterodyne. Each version overcomes the problems with the previous one, and the lastest one has the similar performance to general-purpose network analyzers when performing the required functions. The HBS has been evaluated extensively by measurement on many solid and liquid phantoms with known optical properties. Results show that the HBS to match the accuracy of the gold-reference prototype, called the Laser Breast Scanner (LBS). In addition, in vivo measurements on a human patient with breast cancer further show that the HBS either matches or outperforms the LBS while costing two orders of magnitude less. |
