**7. Chapter summary**

In this chapter, main biomedical sensors, devices and biological measurement systems are introduced to make readers understand present bioinstrumentation in market. The common biomedical sensors are narrated here to make readers grasp their basic sensing principle such as heart sound sensor, blood flow sensor and enzyme sensor. Furthermore, basic charge, current, voltage, power and energy used in biomedical engineering are explained to design some detecting circuits. Besides above, signal filters and operational amplifiers are also described and some advice or opinions are given out to give readers some available references. The basic detecting blocks of biomeasurement system are provided to quickly design relative bioinstrumentations. Readers need to carefully learn the content of biomedical sensors, signal filters, operational amplifiers for bioinstrumentation.
