Learning Forum

[odurney]

I am using OAPs in my current design.  Can Zemax draw an OAP with uniform edge thickness and a flat back surface?  I would like to create OAPs with edges that are perpendicular to the back surface and close to uniform thickness all the way around the periphery.  I only see a standard wedge shape and 'curve' shape available.  Please advise.

[Niki Papachristou]

Hi Oderney,

Thank you for reaching out to us! May I ask you if you have explored the Draw surface properties option within your designs? I think that this mighrt be a good solution for you: Draw (surface properties), it also includes the "Flat To Next Surface" option as well.

Let me know if that helped you or you need further assistance.

Kind Regards,

Niki 

[odurney]

Yes, I have tried all the combinations in the Draw tab.  Strangely, none of the choices from the 'Draw Edges As:' pulldown menu seem to do anything... they all appear the same in both the 3D Layout and Shaded Model viewers.  However, the choices in the 'Mirror Substrate:' pulldown menu do change the form factor of the optic.  But, none of them creates a uniform-ish edge thickness form factor.  Aside from creating a custom volume in Part Designer, is there something I am missing.  Please advise.

[Niki Papachristou]

Hi Odurney,

Can you send some helpful screenshots of your desing? This way I will try to replicate what you are trying to do and find a solution for you.

Kind Regards,

Niki

[odurney]

I cannot send this exact design... but I will create and send a simple OAP design.  The problem is the same.

[odurney]

Attached is a screenshot of a simple, single OAP Zemax design.  It shows the 'Flat' form factor with the classic wedge profile.  I am interested in creating a form factor similar to the attached illustration.

 

[tariq.islam]

 

You can set the mirror substrate to “Curved”, which will give it a form factor similar to what you’re looking for.

 

You can also refer to the help file, which describes this in more detail. Draw (surface properties)

[odurney]

 

Thank you for the tip.  I am aware of the curved substrate choice.  However, it is not what I want.  If the edges of the substrate were perpendicular to the mechanical axis of the OAP, I could make it work.  But, they are slanted… creating a curved parallelogram.

 

[Chris Normanshire]

Hello.

If you convert you OAP from a Standard surface type to an Off-axis Conic Freeform surface then you be able to get the profile you require. Please see this post (Convert a Standard off-axis conic into an Off-Axis Conic Freeform | Zemax Community) on the old Zemax community for instructions on how to perform the conversion.

Kind regards,

Chris

[odurney]

This looks similar to the 'curve' form factor, but the edges are perpendicular to the mechnical axis.  Is it possible to have the back surface flat?  I will practice.  Thank you for the advice.

[Chris Normanshire]

Sure. The off-axis conic freeform works with both curved and flat substrate drawing options. In both cases the edges are perpendicular to the mechanical axis.

[odurney]

This is perfect.  I am having some trouble following the instructions... need to figure out what is wrong.  How would the instructions change of the OAP is after the focal plane?

[odurney]

How can I contact Erin Elliott directly?

[odurney]

Nevermind... I figured it out.  Thanks everyone for your help.

[odurney]

Actually, it would be helpful to understand how the OAP after the intermediate focal plane is adjusted to an Off-Axis Conic Freeform.  Please provide instructions or an example.  Thank you.