Achromatic Doublets φ25mm Focal Length 80mm　DLB-25-80PM

Feature

• By combining two lenses with different refractive index wavelength dispersion into a single lens, chromatic aberration and spherical aberration can be reduced compared to a single spherical lens.
• It can be used as a telescope objective lens or a collimating lens for laser experiments.
• Optimization by lens design results in little change in focal length across the visible range.
• Since not only chromatic aberration but also spherical aberration are well corrected, it is ideal as a collimating lens for laser.
• It is corrected not only for aberrations of the on-axis object point, but also for off-axis coma and astigmatism.
• It can be used for imaging systems such as telescope objective lenses and microscope imaging lenses.
• It can be selected according to your specifications from a wide range of variations, subdivided by outer diameter size and focal length.
• Air gap type condensing lens (NYTL/NYDL) for laser processing is also available.
• * Use an achromatic lens when you want to focus an image at infinity or when you want to use a point light source that is parallel to the image.
• Sufficient optical performance cannot be obtained when the camera is used for close-range imaging.
• * The chromatic lens has an orientation that allows parallel light to enter the lens.
• * This function allows parallel light to enter from the side of the face with a small radius of curvature (the face pointed to by the arrow).
• * When parallel light is incident from the opposite side, chromatic aberration and spherical aberration occur, and the condensing spot becomes larger.
• Chromatic aberration may increase when the camera is used at wavelengths other than visible light.
• * Also, transparency may be reduced.

Specifications

• [ common specification]
• Material: BK7, SF2
• Design wavelength: Blue: 486.1nm, Green: 546.1nm, Red: 656.3nm
• Coating: Reflective prevention film
• Adhesive: Ultraviolet curing type adhesive
• Laser durability: 0.3J/cm2 (pulse width 10ns, Repeat frequency 20Hz)
• Scratch - dig: 40?20
• Effective diameter: 90% of the outer diameter
• [Individual specification]
• Outer diameter φD: φ25mm
• Focus distance f: 80mm
• Edge thickness te: 6.2mm
• Center thickness tc: 8.5mm
• Back focus fb: 75.9mm
• Eccentricity: ＜1′
• RoHS conform product