Patent ID: 8514181
Filing Date: 2013-08-20
Classification: G06F

Abstract:
1. A pressure sensitive and luminous keyboard, comprising: a base; plural keys disposed over said base, wherein when each of said plural keys is depressed, a sensing signal is generated in response to a pressure exerted on said depressed key; a membrane switch circuit module arranged between said base and said plural keys, wherein said membrane switch circuit comprises a pressure detecting circuit for detecting said pressure, thereby generating a corresponding pressure-strength sensing voltage, wherein said pressure detecting circuit comprises plural pressure detecting elements, and each of said plural pressure detecting elements comprises a high-impedance detecting contact and a low-impedance detecting contact, wherein when one of said plural keys is depressed in response to a first pressure, said high-impedance detecting contact and said low-impedance detecting contact corresponding to said depressed key are contacted with each other to have a first contact area, so that said pressure detecting element has a first impedance value, wherein when one of said plural keys is depressed in response to a second pressure higher than said first pressure, said high-impedance detecting contact and said low-impedance detecting contact corresponding to said depressed key are contacted with each other to have a second contact area greater than said first contact area, so that said pressure detecting element has a second impedance value higher than said first impedance value, wherein said pressure detecting circuit further comprises a detecting resistor, which is grounded and has a detecting impedance value, wherein said plural pressure detecting elements are respectively connected with said detecting resistor in series, and said pressure detecting circuit generates said pressure-strength sensing voltage according to said detecting impedance value and said first impedance value or said second impedance value, wherein when said pressure detecting circuit generates a first pressure-strength sensing voltage according to said detecting impedance value and said first impedance value, said controlling unit judges that said depressed key is depressed in response to said first pressure; an illumination module arranged between said base and said plural keys for emitting either a first light beam or a second light beam; a controlling unit connected with said membrane switch circuit module and said illumination module for judging a strength of said pressure according to said pressure-strength sensing voltage, and controlling said illumination module to emit either said first light beam or said second light beam according to said strength of said pressure, wherein said controlling unit controls said illumination module to emit said first light beam, wherein when said pressure detecting circuit generates a second pressure-strength sensing voltage according to said detecting impedance value and said second impedance value, said controlling unit judges that said depressed key is depressed in response to said second pressure, and said controlling unit controls said illumination module to emit said second light beam.