Based on the present invention, superior compact spectrometers may be constructed and integrated into a cellular phone, or attached to a cellular phone. Such a cellular phone may be a PDA phone, which supplies electrical power to the said spectrometer, provided with data storage, signal processing capability, and real-time display. As a combined standalone system, it allows spectroscopic measurements to be fulfilled in real-time applications in field, and results can be sent out in wireless communication to a remote station or to another cellular phone user in order to share the measurement results right away. When the system is used with a laser to function as a Raman spectrometer system, it can fulfill many daily routine tasks encountered by ordinary civilians, for example, the blood glucose monitoring for diabetes patients at home in a non-invasive manner.