J. Eur. Opt. Society-Rapid Publ. 22, 42( 2026) 413
Figure
11. Spot diameter vs field of view of the generated lens Figure 10 a) with a total field of view of ± 2.5 °.
Figure 10. Example of an achromat designed with the Saddle Point Construction and a reduced glass map for an object field of 2.5 ° and spot size comparison with a Thorlabs achromatic cemented doublet.( a) 2D Lens drawing of the system.( b) Spot Diagram of the system with Airy disk at reference wavelength displayed.( c) Spot diagram of the Thorlabs AC254-100-A achromatic cemented doublet.
AC254-100-A and Edmund Optics reference 47-641. As shown in Figure 7, the SPC method designed achromatic cemented doublets perform spot diameter approximately half the size of those produced by A. Szulc [ 16 ] andthe off-the-shelf achromatic cemented doublets. The corresponding spot sizes and configurations are presented in Table 3, where Ri are the radius of curvature of sequential
Figure
12. Spot size of an SPCM generated doublet optimized with weights of 5 and 1 for field angles of 0 ° and 2.5 °.
surfaces, tj are the center thickness of the two lenses and s’ the back focal length of the achromatic cemented doublets.
To ensure the materials selected by the SPC method above are optimal, the diagram in Figure 6 was used to trace vectors connecting each pair of materials, allowing for the calculation of DU PC 2
= U j and their separation. As shown in Table 5, all selected pairs satisfy the condition on DU PC 2
= U j. However, the minimum separation criterion was not met for two glass combinations: N-PK51 with N-LASF41, and N-PK52A with N-LASF41. But, the deviations for these two pairs are minimal, and the combinations do not involve glasses of the same type, suggesting that their inclusion remains acceptable within the context of the