Which of the following is NOT a device typically used in laser therapy?

High-voltage discharge devices are not commonly used in laser therapy practices. In laser therapy, the focus is primarily on devices that generate or emit focused light through laser diodes, which are typically handheld for targeted applications. Larger therapeutic lasers are also designed specifically for engaging deeper tissues and providing therapeutic benefits. Home-use laser gadgets are emerging as accessible options for consumers, but they generally lack the precision and power of clinical devices. In contrast, high-voltage discharge devices relate more to electrical therapy or other methods rather than laser technology. Thus, the correct answer highlights how laser therapy specifically utilizes focused light rather than electrical discharge for therapeutic purposes.