Howie Glatter Holographic Attachment for Laser Collimator - Square Grid

You can opt for holographic attachments that screw into the laser aperture and feature a white screen front surface. These attachments include an optical element that disperses most of the laser light into a symmetrical pattern diverging around the central beam. This projected pattern serves the purpose of aligning optical elements by ensuring symmetry with the edge of the optic.

Three patterns are available:

10 x 10 Line Square Grid Pattern: This pattern, provided as standard unless otherwise specified, is the widest. It spreads over 21 degrees, allowing for the centering of optics as fast as f/2.7. Recommended for general use, it suits the fastest telescopes commonly encountered.

Nine-Concentric Circle Pattern: Spanning 10 degrees, this pattern is suitable for optics around the focal ratio of f/5.7 or slower. It reaches the edge of optics effectively and is brighter than the square grid pattern due to the laser light being spread over a smaller area. This makes it particularly useful with Cassegrain scopes, where the impact of the pattern on mirror surfaces is scrutinized. The projected pattern is visible primarily due to scattered light from dust, dirt, or optical imperfections, making a brighter pattern advantageous, especially with very clean mirrors.

Cross-Hair and Circle "Scope" Pattern: Covering 10 degrees, this pattern is useful for primary collimation in non-Barlowed, conventional Newtonian telescopes. In this context, the primary mirror is adjusted to reflect the central laser beam back into the collimator's laser aperture. The cross-hair intersection facilitates easy visualization of when the return beam is precisely centered on the collimator face.