A laparoscopic bipolar electrosurgical instrument for sealing tissue includes a handle having an elongated tube affixed thereto. The cap is formed into a bag and is shaped into a wedge that gets thinner towards the front, and the cap has a window for exposing the conductive pad of the printed circuit board. In some embodiments, the lid may include an overlay moveable between at least one open position and at least one closed position. A fluid actuator is configured to selectively prevent the intake valve from moving to the first position. The transfer unit moves to the second position together with the door panel, and when the door panel is in a generally fully opened state, the transfer unit is movable to the first position independently of the door panel, thereby improving the ease of maintenance in the vicinity of the transfer unit. The color filter can realize high contrast and high brightness.