MachineVideoLenses and Analysis

jsmcu

A few days someone tell me about the YTOT CUP optical design competition, which had three problems:
1st security surveillance lenses design,2nd the machine video lenses design,3rd continuous zoom optical system.
As show fields before i had great interest in the machine video lenses system, so takes me half of the day to design the lenses below.

      

Fig1  Optical Systems

In the fig1 optical systems, there are 12 pieces of glasses and 8 groups, the stop diaphragm in the middle of the sturcture which comfortablely correct the field aberration such as the field curvature and so on. Multipe balsaming lens gruops are responsible for the color aberration. As you see in the fig1, the S6 of the doublet concave lens and the S13 surace be used to control the curvature of field which commonly known as waist drum. Obvious, the spherical aberration is veryly small because of  a lot of variance.

Fig2 Modulation Transfer Function

MTF value of every field not less than 0.3 at the 200 cylces per millimeter

       Fig3 Uniformization Relative Illumination

The parameter requirement VS the design values show as follows:

File : C:\ZMX2009USER\1002000-1200-2800MA-purple_05_100_n50.zmx
Title: YTOT CUP COMPETITION
Date : 2021/6/18

Lens Parameters:
PROJECT                      TARGET                 DESIGN                   ACCEPT(Y/N)
Construction               not specified        12pieces-8group                     Y
Spectrum range          486-656(Center 588) um                                    Y
Image Cycle Diameter     11.4mm            11.4mm                                 Y
f'                                        12mm                   11.9mm                            Y
F/#                                     <2.8                       2.6                                   Y
FOV                           not specified          51.8deg                                  Y
Distortion                        <=2.5%                    2.4%                                Y
RI                                    >=70%                   74.84%                              Y
CRA                             0~5.00deg               5.00deg                               Y                             
BFL                                >=8mm                   13.446mm                          Y
TOTR                           <=55mm                  54.784mm                           Y
Dimension                smart compact       19.3X41.3mm                           Y     
Weight                           10.3g
Filter+CG                       1mm                   1mm                                        Y

MACRO ELAPSED TIME: 0.7 Seconds 2021/06/18

Except for the regular evaluation index we try to analysis the working distange performance of the optical system using the exploit tools below:It is concise and to the point as shown in the fig4~6 depth of field MTF at the different cut-off frequency in  the object space.

fig4  depth of field MTF at the 200 cylces per millimeter

The effective working distance range from -140mm to the 375mm @200 cylces per millimeter is well perfromance in the photograph.

fig5  depth of field MTF at the 150 cylces per millimeter

The effective working distance range from -155mm to the 835mm @150 cylces per millimeter is well perfromance in the photograph.

Fig6  depth of field MTF at the 100 cylces per millimeter

The effective working distance range from -180mm to the 5005mm @100 cylces per millimeter is well perfromance in the photograph.

According to the above analysis we know this design when the working distance range at the MTF 100~150  cylces per millimeter can satisfy the competiton requirements 100mm-2000mm.

Fig7 Strictest depth of field in the object space

The systems has a strictest depth of field in the object space corresponding to the depth of focus. From the above diagram and the mathematical iterative calculation program easily accept the theoretical values is 20 millimeter which very beneficial to the assembler or correspondent.

Fig8 DISTORTION

Fig9 TV DISTORTION

Fig8~9 shows the system dist diagram, the dist is similar to the tv dist. and the maximum value of the TV dist is small then 1%, probablye half of the maximum dist value.

Fig10 electrocardiography

The fig10 electrocardiography curve is  tiny jump and relative conncentration, means stability of the systems in the fabrication.
  
the desing as show before is very roung, a lot of things are not to taken into account.
of course a production design need to do more steps like this  and also consider the balance of the aberrations, the analysis and adjust of tolerance, thermal analysis...not limited to this in practice.

-------------------------------------------
The charm of optical design is that there is no uniqie in the reality, dare to innovate and forge ahead is our most powerfu weapon.
Welcome everybody to upload or share yours unique and extraordinary design, anything experience or diagram is well.

signing Zemax Chinese MCBBS
2021/6/19