Variable focal length lens device
A variable focal length lens device includes: a lens system whose refractive index is variable in response to an inputted drive signal; an image detector for detecting an image of a target object through the lens system; a lens controller for outputting the drive signal and an illumination signal; and a lens operation unit for adjusting a frequency and amplitude of the drive signal outputted by the lens controller and an image-detection timing for the image detector. The lens controller includes a resonance-lock controller for tuning the drive signal to a resonance frequency of the lens system. The lens operation unit includes a resonance-lock operation unit for switchably enabling and suspending the resonance-lock controller.
1. A variable focal length lens device comprising:
a lens system whose refractive index is variable depending on an inputted drive signal;
an objective lens disposed in an optical axis common to the lens system;
an image detector configured to detect an image of a target object through the lens system and the objective lens;
a lens controller configured to output the drive signal; and
a lens operation unit configured to adjust a frequency, an amplitude and a maximum drive voltage of the drive signal outputted by the lens controller, wherein
the lens controller comprises a resonance-lock controller configured to lock the frequency of the drive signal to a variable and temperature-dependent resonance frequency of the lens system, and
the lens operation unit comprises a resonance-lock operation unit configured to switch enabling and suspending the resonance-lock controller.
2. The variable focal length lens device according to claim 1 , wherein
the lens controller is in a form of a dedicated hardware, and
the lens operation unit is in a form of a computer system configured to run a dedicated software.
3. The variable focal length lens device according to claim 1 , wherein
the lens operation unit further comprises an operation interface,
the operation interface comprises a main screen, a setting portion for the frequency and the amplitude of the drive signal, and an operation portion for enabling and suspending the resonance-lock controller, the setting portion and the operation portion being displayed on the main screen, and
a setting portion for an image-detection timing of the image detector and a setting portion for the maximum drive voltage of the drive signal are each displayed on a sub screen independent of the main screen.