SIGMAKOKI YAGLaser Focusing Lens Focal Length 20mm　NYTL-25-20PY1

Feature

• This is an air-gap type acromatic condensing lens with no adhesive attached to the lens.
• It is used as a condensing lens for a 532 nm high-power laser machine with a built-in coaxial epi-illumination observation system.
• Chromatic aberration is corrected in a wide wavelength range centered around 532 nm by optimization based on lens design.
• For lenses with a focal length of 60 mm or more, laser collimation can be narrowed down to a spot diameter that is almost diffraction limited.
• Since the lens is coated with an anti-reflection film, the loss of light due to reflection is small, and the beam can be concentrated efficiently.
• A separately sold protective glass can be installed to protect the lens from flying light caused by laser processing.
• A special lens holder (LHF-M34-30) is available for fixing the condenser lens.
• * Use the condenser lens when you want to focus an object at infinity, or when you want to use the point light source as parallel light.
• Sufficient optical performance cannot be obtained when the camera is used for close-range imaging.
• * The condenser lens has an orientation that allows light to enter.
• * Be sure to allow parallel light to enter from the upper side (look at the engraving on the side of the lens barrel upright).
• * Doing so can cause chromatic aberration and spherical aberration to become large, which can increase the size of the focus spot, and can cause blurred images.
• If you use the instrument outside the specified wavelength range, chromatic aberration may increase and transmittance may be reduced.
• * When using with a high-power laser or near a light source that emits heat, the condenser lens may become hot and the focal length of the condenser lens may change.
• * Heat dissipation measures are necessary when irradiating for a long time.
• * If you want to reduce the condensing spot diameter, widen the incident beam diameter (1/e^2) to about half the effective diameter of the condensing lens.

Specifications

• [ common specification]
• Material: Crown series glass - (air gap) - flint series glass
• Frame material: Aluminum surface treatment: Black anodic oxide
• Design wavelength: 1064nm, 632.8nm
• Coating: 1064nm, for 632.8nm reflective prevention film
• Incident allowable angle: ±1°
• Laser durability: 1J/cm2 (pulse width 10ns, Repeat frequency 20Hz)
• [Individual specification]
• Lens outer diameter φD: φ25mm
• Focus distance f: 20mm
• Outer diameter φDc: φ32mm
• Effective diameter φDe: φ20mm
• Length L: 22mm
• Screw for fixing Ma: M29 P0.75
• Mounting screw Mb: M22 P0.75
• Screw length A: 6mm
• NA : 0.5
• WD: 9mm
• RoHS conform product