Extremely compact and light-weight optical systems, apparatus, devices and methods to image miniature displays. Such systems include, for example, head-mounted projection displays (HMPD), head-mounted displays (HMDs), and cameras for special effects, compact microscopes and telescopes as well as applications in which magnification and compactness are design criteria. The invention includes an ultra-compact imaging system based on microlenslet arrays and demonstrates that such a system can achieve an object-to-image distance as low as approximately 1.7 mm. with the usage of commercially available microlenslet arrays. The replacement of bulk macro-optical system by multi-aperture micro-optics is achieved.