功能

• A reflective ND filter whose transmittance can be varied by rotating (or going straight) the filter.
• It can be used for measurement experiments that require light intensity adjustment or for adjusting the brightness of observed images by the camera.
• The amount of light can be continuously varied, and any brightness can be selected.
• Because the transmittance varies logarithmically with the amount of movement, dynamic light adjustment is easy.
• Since the shape of the filter is very thin, it can be inserted into a small gap in the optical system, and the amount of light can be easily adjusted.
• VND-U uses a synthetic quartz substrate with good ultraviolet transmission.
• Use as a variable ND filter for ultraviolet.
• A variable beam splitter (VBS) is also available that can change the transmittance by changing the angle of incidence.
• * The round variable ND filter has a very fragile shape.
• * When fixing with the inner diameter, be careful not to apply force to one part of the glass surface.
• * Since chromium film has absorption, it cannot be used for high-energy pulsed laser.
• * When a high-power laser is injected into the filter, the beam may focus due to the thermal lens effect.
• * Use a variable beam splitter (VBS) for high power lasers and high energy lasers.
• * The laser beam reflected by the surface of the filter is dangerous.
• * Terminate the reflected beam so as not to irradiate the worker.
• * When the laser beam enters the filter normally, the light reflected by the filter returns to the laser light source.
• * When there is such a return light, the laser oscillation becomes unstable.
• * To prevent the return light from returning to the laser source, tilt the filter slightly.
• * Injecting a large beam into the variable type ND filter may cause an intensity difference in the beam.
• * Use the filter with a thin beam.