In situ, photoirradiation solid-state nuclear magnetic resonance (NMR) spectroscopy is designed for optical irradiation from the top part of a zirconia rotor through a glass cap, which makes it possible to efficiently irradiate the inside of the rotor. This experimental method has made it possible to observe photo-intermediates of photo receptor membrane proteins, such as sensory rhodopsin I (SRI), sensory rhodopsin II (SRII), and bacteriorhodopsin (BR). In SRI, green light generates M-intermediates, which exhibit positive phototaxis, while blue light generates P-intermediates, which exhibit negative phototaxis. In SRII, green light generates M-intermediates and blue light generates O-intermediates. In bacteriorhodopsin (BR), CS*- and M-intermediates were first observed using photoirradiation solid-state NMR spectroscopy. The microwave irradiation NMR spectrometer was developed in-house by modification of a commercial NMR spectrometer. A flat long copper ribbon was used as a capacitor and a half turn of copper ribbon at the edge was used as an inductor for the microwave resonance circuit, which was coaxially inserted inside the radiofrequency induction coil, and allowed NMR signals to be observed under microwave irradiation conditions. The temperature of N-(4-methoxybenzylidene)-4-butylaniline (MBBA) during microwave irradiation was estimated by measuring the temperature-dependent chemical shifts, whereby different protons were found to indicate significantly different temperatures in the molecule. Liquid crystalline phase and isotropic phase correlation 2D NMR spectra were observed using pulsed microwave irradiation for rapid temperature jump experiments. Non-thermal microwave heating processes were discussed in ethanol-hexane mixed solution under microwave irradiation.