Synchronization signal generating device and display apparatus

A display apparatus comprising:

• a synchronization signal generating device configured to output a display vertical synchronization signal, to a display unit;
• a control unit configured to control the synchronization signal generating device and to read out a video signal stored in a buffer to provide the video signal as the input video signal to the display unit;
• and
• a display vertical synchronization signal to be used for display of an input video signal, the display unit being capable of providing display based on the input video signal if a vertical synchronization interval of the input video signal is within a range of a compensation interval, the compensation interval comprising the range between a minimum vertical synchronization interval and a maximum vertical synchronization interval, the synchronization signal generating device comprising:
• a cycle measuring unit configured to measure the vertical synchronization interval of the input video signal;
• a phase difference detecting unit configured to detect a phase difference between an input vertical synchronization signal based on the input video signal and the display vertical synchronization signal;
• and
• a vertical cycle determining unit configured to determine a cycle of the display vertical synchronization signal based on a measurement result of the cycle measuring unit and a detection result of the phase difference detecting unit so that the phase difference is decreased within the range of the compensation interval and to determine 1/n of the cycle of the display vertical synchronization signal as a cycle of an n-times speed vertical synchronization signal.

A display apparatus comprising:

• a synchronization signal generating device configured to output, to a display unit, a display vertical synchronization signal to be used for display of an input video signal, the display unit being capable of providing display based on the input video signal if a vertical synchronization interval of the input video signal is within a range of a compensation interval between a minimum vertical synchronization interval and a maximum vertical synchronization interval, the synchronization signal generating device comprising:
• a cycle measuring unit configured to measure the vertical synchronization interval of the input video signal;
• a phase difference detecting unit configured to detect a phase difference between an input vertical synchronization signal based on the input video signal and the display vertical synchronization signal;
• and
• a vertical cycle determining unit configured to determine a cycle of the display vertical synchronization signal based on a measurement result of the cycle measuring unit and a detection result of the phase difference detecting unit so that the phase difference is decreased within the range of the compensation interval and to set the cycle of the display vertical synchronization signal based on the measurement result of the cycle measuring unit if an occurrence of the input vertical synchronization signal within the range of the compensation interval is detected based on the phase difference;
• and
• a control unit configured to control the synchronization signal generating device and to read out a video signal stored in a buffer to provide the video signal as the input video signal to the display unit.