This material is essentially Chapter 9 of the book Software Development in Pascal by
Sartaj Sahni, NSPAN Printing and Publishing, 1993. It is reproduced here with permission
of the publisher.
zemax源碼：
This DLL models an anamorphic aspheric surface.
This surface is essentially an even aspheric surface with different terms for
the x and y directions.
The sag is given by:
Z = ((CX*x*x)+(CY*y*y)) / (1 + sqrt(1-((1+KX)*CX*CX*x*x)-((1+KY)*CY*CY*y*y)))
+ AR*( (1 - AP)*x*x + (1 + AP)*y*y )^2
+ BR*( (1 - BP)*x*x + (1 + BP)*y*y )^3
+ CR*( (1 - CP)*x*x + (1 + CP)*y*y )^4
+ DR*( (1 - DP)*x*x + (1 + DP)*y*y )^5
Note the terms AR, BR, CR, and DR ... have units of length to the -3, -5, -7, and -9 power.
The terms AP, BP, CP, and DP are dimensionless.
The surface is rotationally symmetric only if AP = BP = CP = DP == 0 and CX = CY and KX = KY.
cordic methods describe essentially the same algorithm that with suitably chosen inputs can be used to calculate a whole range of scientific functions including sin, cos, tan, arctan, arcsin, arccos, sinh, cosh, tanh, arctanh, log, exp, square root and even multiply and divide.
the method dates back to volder [1959], and due to its versatility and compactness, it made possible the microcoding of the hp35 pocket scientific calculator in 1972.
here is some code to illustrate the techniques. ive split the methods into three parts linear, circular and hyperbolic. in the hp35 microcode these would be unified into one function (for space reasons). because the linear mode can perform multiply and divide, you only need add/subtract and shift to complete the implementation.
you can select in the code whether to do the multiples and divides also by cordic means. other multiplies and divides are all powers of 2 (these dont count). to eliminate these too, would involve ieee hackery.
.NET Remoting is very important in distributed environments. This book essentially deals with the core concepts of .NET remoting along with some working examples. A must read.
Most circuit designers are familiar with diode dynamiccharacteristics such as charge storage, voltage dependentcapacitance and reverse recovery time. Less commonlyacknowledged and manufacturer specifi ed is diode forwardturn-on time. This parameter describes the timerequired for a diode to turn on and clamp at its forwardvoltage drop. Historically, this extremely short time, unitsof nanoseconds, has been so small that user and vendoralike have essentially ignored it. It is rarely discussed andalmost never specifi ed. Recently, switching regulator clockrate and transition time have become faster, making diodeturn-on time a critical issue. Increased clock rates aremandated to achieve smaller magnetics size; decreasedtransition times somewhat aid overall effi ciency but areprincipally needed to minimize IC heat rise. At clock speedsbeyond about 1MHz, transition time losses are the primarysource of die heating.
This application note describes how the existing dual-port block memories in the Spartan™-IIand Virtex™ families can be used as Quad-Port memories. This essentially involves a dataaccess time (halved) versus functionality (doubled) trade-off. The overall bandwidth of the blockmemory in terms of bits per second will remain the same.
This application note describes how the existing dual-port block memories in the Spartan™-IIand Virtex™ families can be used as Quad-Port memories. This essentially involves a dataaccess time (halved) versus functionality (doubled) trade-off. The overall bandwidth of the blockmemory in terms of bits per second will remain the same.
Contains a complete archiver by Haruhiko Okumura. The archiver uses
an LZ engine whose output is compressed with static Huffman. The
file is chopped into pieces which all get their own independent
set of Huffman tree s. ARJ 2.41, ZIP 2.0 and PKZIP 2.04g use
essentially the same method. ZOO and LHA even use excactly the
same method.
The tar file contains the following files:
ptfsf.c: heart of the perfect TFSF code
ptfsf.h: header file for same
ptfsf-demo.c: FDTD code which demonstrates use of perfect TFSF code. essentially this program used to generate results shown in the paper
ptfsf-file-maker.c: code to generate an incident-field file using the "perfect" incident fields
ptfsf-demo-file.c: FDTD code which uses the perfect incident fields stored in a file
fdtdgen.h: defines macros used in much of my code
Makefile: simple make-file to compile programs
Also include are some simple script files to run the programs with reasonable values.
The code assumes a two-dimensional computational domain with TMz polarization (i.e., non-zero field Ez, Hx, and Hy). The program is currently written so that the incident field always strikes the lower-left corner of the total-field region first. (If you want a different corner, that should be a fairly simple tweak to the code, but for now you ll have to make that tweak yourself.)
光學設計軟件zemax源碼：
This DLL models an nular aspheric
surface as described in:
"Annular surfaces in annular field systems"
By Jose M. Sasian
Opt. eng. 36 (12) P 3401-3401 December 1997
This surface is essentially an odd aspheric surface with an offset in the aspheric terms.
The sag is given by:
Z = (c*r*r) / (1+(1-((1+k)*c*c*r*r))^ 1/2 ) + a*(r-q)^2 + b*(r-q)^3 + c*(r-q)^4 + ...
Note the terms a, b, c, ... have units of length to the -1, -2, -3, ... power.
