tailieunhanh - Nonimaging Optics Winston Episode 9

Tham khảo tài liệu 'nonimaging optics winston episode 9', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Results 229 To compare the imaging performance of different systems and for different object points a single number derived from the MTF is more useful than the full curves. One possible criterion is the equivalent bandwidth which is defined for the tangential MTF and the sagittal MTF as fc T f MTF2 fT 0 dfT fcs f MTF2 0 fs dfs 0 0 Observe that the axial symmetry of the optical systems implies fc T fc S for the axial object point. As an example both the RX designed with a 3 and the f planoconvex spherical lens optimally defocused have fc T fc S for normal incidence. When a single NA value can be applied to the image points to be studied then fc T fc S for all the object points in a perfect MTF because the perfect MTF has rotational symmetry in the variables fT fS . Direct calculations of the equivalent bandwidth of the perfect MTF which depends only on the values of NA and b demonstrate that dependence on b is small when NA is fixed. Neglecting this dependence it is easy to calculate the fc of the perfect MTF as X NA l. For instance A and b 77 which are the values of the RXs gives fc 845 mm-1. Figure shows fc T and f S as a function of the angle of incidence d for the RX concentrators designed with a 3 and the aplanatic RX and their diffraction limit of 845 mm-1. All the RXs attain a maximum of fc T for d a. For 8 0 the smaller a the greater fc T. The same behaviour is observed in fcS although the maximum is obtained at d 2a 3 and is less abrupt. In the case of the aplanatic RX the value of fc T and fc S equals the diffraction limit for d 0. Let us call fc ff the smallest . the poorest of fc T and fc S for each angle of incidence. It is a global indicator of the imaging performance at the incidence angle ft In the case of the former RXs fcTff fc S d . Thus fc Q fC S . This fc is shown in Figure . Let us consider the one-parametric family of RX concentrators designed with the input parameters f dA and

TỪ KHÓA LIÊN QUAN
TÀI LIỆU MỚI ĐĂNG
10    155    0    24-04-2024
15    183    0    24-04-2024
75    137    0    24-04-2024
11    99    0    24-04-2024
185    97    0    24-04-2024
3    122    0    24-04-2024
380    91    0    24-04-2024
crossorigin="anonymous">
Đã phát hiện trình chặn quảng cáo AdBlock
Trang web này phụ thuộc vào doanh thu từ số lần hiển thị quảng cáo để tồn tại. Vui lòng tắt trình chặn quảng cáo của bạn hoặc tạm dừng tính năng chặn quảng cáo cho trang web này.