Non-disposable cameras are arguably a more sustainable product than disposable; however, Kodak Disposable Cameras are a good example of designing a product that is to be used once by the user but several times by the manufacturer.
Question the premise of the design: A light, focus-free camera provides an affordable, convenient solution for casual photographers. The collection/development system that has been established allows users to easily part with the camera and still feel like they have retained their purchase (photos) while providing a reliable recycling and reuse network.
Optimize manufacturing processes: These cameras take advantage of the efficiencies of high-volume manufacturing and simple manual assembly (no fixtures, gauges or specialty tools are required to assemble).
Design for upgradability: The enclosure is reusable as are many of the internal components that can be replaced when worn. Internal counters in some models track how many times components have been reused.
Make it modular: The metal and plastic components can be separated for material recycling or reuse. The enclosure and many of the internal components can be reused with a new roll of film. Up to 86% of the material can be reused.