This study offers an in-depth evaluation of hemispherical energy analyzers (HEAs), with a particular focus on key components such as electron sources, lens systems, electrostatic mirrors, and detectors. Based on a review of 179 research papers, 47 significant studies were identified, highlighting advancements and challenges in HEA design. Key findings emphasize the role of advanced electron sources, including Schottky emitters and transition-edge sensors (TES), in improving energy resolution and emission stability. The analysis also underscores the effectiveness of multipole and paracentric lens systems in enhancing electron beam focusing and energy dispersion. However, challenges persist in optimizing the integration of these components, particularly regarding electrostatic field interactions. The study concludes that further innovation is needed in structural design to achieve optimal balance in compactness, stability, and functionality, especially for space applications, while addressing limitations in detector sensitivity and energy resolution.