Recent progress of infrared photoreflectance and modulated photoluminescence techniques was outlined with spe-cial attention focused on the significant improvement of signal-to-noise ratio, spectral resolution and time consumption rela-tive to the conventional techniques. Application of these techniques to molecular beam epitaxially grown HgCdTe films wasgiven as examples, from which the potential impact of the techniques was foreseen on the optical study of narrow-gap semi-conductors and inter-subband transition of wide-gap semiconductors with low-dimensional structures.邵军（中科院上海技术物理研究所红外物理国家实验室,上海,200083）马丽丽（中科院上海技术物理研究所红外物理国家实验室,上海,200083）吕翔（中科院上海技术物理研究所红外物理国家实验室,上海,200083）吴俊（中科院上海技术物理所材器中心,上海,200083）李志峰（中科院上海技术物理研究所红外物理国家实验室,上海,200083）郭少令（中科院上海技术物理研究所红外物理国家实验室,上海,200083）何力（中科院上海技术物理所材器中心,上海,200083）陆卫（中科院上海技术物理研究所红外物理国家实验室,上海,200083）褚君浩（中科院上海技术物理研究所红外物理国家实验室,上海,200083;华东师范大学成像信息联合实验室,上海,200062）