| Optical diagnostics have the potential to provide noninvasive, real-time diagnosis of tissue, and are receiving extensive attention as well as being rapidly developed. To facilitate the diagnosis of early cervical cancer, a system based on frequency domain near-infrared diffuse light detection technique has been developed in this group. This article deals with some aspects of the system towards to clinical application. Firstly, to be applicable in the clinical use, the developed frequency domain system is optimized and assembled and an endoscopic optode for cervix tissue detection is designed. On the platform of LabVIEW, the instrument software control and the user-interface are realized.Secondly, the article deals with the method for eliminating the intrinsic parameters of the measurement system that include the intrinsic amplitude attenuation and intrinsic phase delay. Several calibration methods are proposed, which are the calibration methods with standard phantom, calibration based on multiple source-detector separations (SDS) detection. And a calibration method which can eliminate the optode coupling coefficient is also proposed. Two phantoms with known optical properties are adopted to verify the system and system calibration methods. Results show that measurement with standard phantom obtains the best agreement with Monte Carlo simulation, with the amplitude error less than 30% and phase error less than 10%.Thirdly, in addition to the previous results, optical parameters reconstructed from the frequency domain measurement with the calibration method of standard phantom demonstrates an error of less than 30% with the phantom's theoretical optical properties. Further more, a phantom with unknown properties is measured with both the time domain and frequency domain technique respectively, and the optical parameters reconstructed from the two results are close to each other.
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