2results about How to "Diffraction reduction" patented technology

The embodiment of the utility model discloses a detection device and a detection system, in the detection device, an electromagnetic shielding structure covers the inner wall of a box body; a signal source of the signal generation assembly is arranged outside the box body, a first electric connector penetrates through the box body, a radio frequency antenna is obliquely arranged in the box body, a parabolic reflector is arranged in the box body, and the radio frequency antenna is located below the parabolic reflector; a test fixture of the signal detection assembly is arranged in the box body, the test fixture is located in a focusing area below the parabolic reflector, a radio frequency signal receiver is arranged on the test fixture, the test fixture is used for mounting an object to be detected so as to cover the radio frequency signal receiver, a second electric connector penetrates through the box body, and a spectrum analyzer is arranged outside the box body. Through the above mode, the radio frequency antenna of the embodiment of the utility model obliquely radiates to the parabolic reflector, so that electromagnetic waves are focused and radiated to the test fixture, the electromagnetic field intensity of the test fixture area is enhanced, errors are reduced, and the accuracy of electromagnetic shielding effectiveness detection is improved.

The utility model discloses a loudspeaker unit with sound resistance regulation function. The diaphragm of the unit is a folded ring type rectangular diaphragm; wherein, the folded ring type rectangular diaphragm comprises a folded ring area, and a hollow part arranged at the center of the folded ring area; the hollow part is covered with a fine hole reticular layer; the outer side of the fine hole reticular layer is covered with an intermediate film, and the covering ratio of the intermediate film is 30% to 70%. The utility model provides a channel for heat dissipation. The intermediate film is covered on the outer side of the fine hole reticular layer, and the covering ratio is 30% to 70%. When the sound wave is transmitted from the diaphragm to the fine hole reticular layer and then spreads outward, the intermediate film will change the propagation path of the sound wave. Due to the partial covering of the intermediate film, it will make the sound wave encounter different medium interfaces (the interface between the intermediate film and air) in the propagation process, thereby generating reflection and transmission phenomena, which is equivalent to adjusting the sound resistance and making the energy distribution of the sound wave more reasonable.