An optical disc apparatus according to the present invention steadily performs a focus jump operation and a track-crossing seek operation relative to an optical disc having a plurality of recording layers. Said needle protective element has an engaging section that engages with an engaging device, which is formed in the vicinity of the needle tip, when the hollow needle is withdrawn from the catheter sleeve. The airflow channel can be alternatively formed between the solar cell panel and other components of the projection device. A method for forming an image using the photosensitive material is also provided. The present disclosure further provides a programmable shared built in self testing architecture utilizing globally asynchronous and locally synchronous methodology for testing multiple memories.