An Elaborate Laser Pen Interactive System In Multimedia Classroom

Based on various kinds of existing equipment and technology research achievements in E-Learning Lab of SJTU, this paper continue to use laser pen interactive system and teaching platform as the object of study, and combine both organically. The system is used in daily educational lectures and after-school system operation. The paper is aimed to design and implement an elaborate laser pen interactive system in multimedia classroom.The system on the basis of the original laser pen interaction system, utilizes USB camera as image acquisition device, transmits wireless control signal between handheld laser pen equipment and software terminal via Bluetooth communication module, and integrates more applicable to the teaching scene functions into a elaborate laser pen interaction system. The research achievement greatly improves the stability, functionality and operability of the laser pen interaction system, making it applicable scenes range broader and increasing equipment convenience.The hardware part of the system is made of a elaborate hand-held laser pen controller and Bluetooth receiver. Each functional buttons and the laser head of elaborate hand-held laser pen controller are set in the places where the presenter is easy to operate and facilitate which integrates Bluetooth communication and laser pointer. Laser head for emitting laser bright spot is easy for speaker to point out the key part in his speech. Bluetooth receiver is the corresponding Bluetooth module with the hand-held laser pen in Bluetooth transmitter, whose is small-sized, easy to carry, so improves the convenience of the whole device. Bluetooth communication has characteristics of longer distance transmission, lower signal bit error rate and higher stability than the original laser pointer which used ordinary communication module. At the same time, its overall production costs are controllable and the module is highly integrated, easier to transplant. Image acquisition part of the system makes use of a USB camera, which provides the original image data to software part for the judgment and handling of the highlights. The cutoff-wavelength filter is configured in front of the camera to filter the natural environment light, which makes retrieval of the highlights significant. USB camera image acquisition frame rate is stable, acquisition pixel is high, and control background is convenient.The software part of the system reorganizes the layout of keys in the existing circumstances, to achieve one key for the switch between functions and remaining four keys for the realization and operation of specific functions. The logic optimization from a combination of strategies improves the features expansion obstacles due to keys insufficiency, and makes it possible to implant more applicable in teaching scene features. The study through optimization and improvement of original software system solves some pre-existing problems in use. Meanwhile, more innovative and useful functions are implanted into laser pen interaction system in software portion, such as adjustable magnifying function and functional support for real-time translation applications and so on. The implantation of these functions reflects practicality and uniqueness of this interactive system more, which brings more interactive and vivid effects for teacher and students in multimedia classroom, and significantly improves system robustness and user experience from software point of view.According to the design of the entire system and the research on related key technologies, this paper has completely achieved an assistant system on teaching and learning, which has been put into use in Multimedia Classroom.