Photopia for SOLIDWORKS Tutorial: Sample 1: 2’x4’ · PDF filePhotopia for SOLIDWORKS® Tutorial: Sample 1: 2’x4’ Troffer Page 1 of 6 1. Begin by opening “2x4 Flour Troffer.SLDASM”

Photopia for SOLIDWORKS® Tutorial:

Sample 1: 2’x4’ Troffer Page 1 of 6

1. Begin by opening “2x4 Flour

Troffer.SLDASM” in

SOLIDWORKS. This file is in the

following location:

C:\Users\Public\Documents\LTI

Optics\Photopia\Sample

Projects\2x4 Fluor Troffer SW\

2. This project has placeholder lamp

geometry, as well as small cones

that show the center of each lamp.

We’ll need to import the Photopia

model for these lamps. On the

Photopia tab in the

CommandManager, click Add

Lamp. Use the drop down to find

the F54T5HO lamp. You can also

Browse lamps to see more

information on each lamp. Once

you have the lamp selected click

to drop the lamp in the project.

General Note: Not all lamps will have detailed SOLIDWORKS geometry in their part files. For some lamps you’ll see a disc with several arrows, where the plane of the disc is photometric horizontal, and the arrows represent the 0° angles. This geometry is centered at the photometric center of the lamp, which corresponds to the 0,0,0 point in Photopia. Typically this is the following location:

COB LEDs: center of front face of phosphor

LEDs with dome: center of actual die

Arc lamps: center of arc To help position these lamps you may need to open the lamp in standalone Photopia and find the position. We are working to get full geometry for as many lamps as possible, but this takes time with over 900 lamps in the library.



3. Select View > Coordinate

Systems and you’ll see the Lamp

Orientation coordinate system

displayed. This shows you the

photometric center and orientation

of the lamp. Now choose Insert >

Mate. Select the Lamp orientation

coordinate system and the tip of the

cone located at the lamp center.

This will move the lamp to the

correct position.

4. Repeat steps 2 and 3 to add and

position the second F54T5HO lamp

at the second cone.

5. There are two ways to assign

appearances. If you want to assign

appearance in the part file. In the

task pane, find the Photopia

Appearances tab and click it to

open the task pane. Choose

PAINT006 and drag this material

onto the end caps and housing,

assigning the appearance to the

entire part. Choose WOF164WT

and assign this to the main curved

reflector. If you prefer to assign

appearance at the assembly level

(not saved in the part file), choose

the part in the model tree, then

double click the appearance in the

Photopia Beta Appearances task

pane, then choose “Apply at

Component Level”. This behavior

varies based on SOLIDWORKS

version.

General Note: Only surfaces with a Photopia Appearance assigned will be sent to the raytracer.



6. Next, we will place a coordinate

system to orient the photometry. In

the FeatureManager design tree,

change the transparency of the

Lens part so that it is visible. Once

visible, choose the part and then

choose Insert > Reference

Geometry > Point and choose

Center of Face.

7. Once the point is inserted at the

center of the lens, choose Insert >

Reference Geometry >

Coordiante System, and select the

Point. You may need to flip the

Coordiante System until the Z axis

is pointing out of the top of the

fixture and the Y axis along the

lamp direction. Remember that the

–Z is Vertical Angle = 0 and that

Positive Y is Horizontal Angle = 0.

You can also change the name of

this Coordiante System so it is easy

to find later.



8. Now that the coordinate system is

set, we can setup the Photometric

Settings. With nothing selected in

the model, select Photometric

Settings from the Photopia tab in

the CommandManager. Set the

Horizontal Test Angles to 0(22.5)90

and the Vertical Test Angles to

0(5)90. Select the Coordinate

System centered at the lens face

that we just created. You can set

the test distance and Luminous

Dimensions here as well. You’ll

see the photometric sphere as a

wireframe, correctly oriented.

9. Select Raytrace Settings, set an

appropriate Ray Count and

Reaction Count. You may now

begin the raytrace by selecting Run

Raytrace.

General Note: Photopia for SOLIDWORKS raytraces with the same mesh that SOLIDWORKS uses for display. SOLIDWORKS will use a fairly coarse mesh for display to improve responsiveness of the model. If your parts are very sensitive to absolute geometry, you will need to increase this display resolution so that Photopia gets the true surface geometry. This setting is under “Tools” -> “Options” -> “Document Properties” -> “Image Quality” -> “Shaded and draft quality HLR/HLV resolution” and should be set as high as possible when the model is very sensitive.



10. After the raytrace has started, you

can view the status and results by

selecting the Results button. You

can open the results in a separate

window so that you can still interact

with the model. There are tabs for

the different output that is avaliable.

11. Next we will add an illuminance

plane. Illuminance planes can be

assigned to any planar face.

12. In a new part, insert a sketch which

is perpendicular to the lamps. Draw

a rectangle in the sketch, and then

convert this rectangle to a planar

face. Make the size as appropriate

to capture the data you wish. Insert

this part into your assembly model

and float it to position it.



13. Select the face and select Add

Illuminance Plane from the

Photopia tab. The face and lower

left corner should be selected. The

front side of the plane is indicated

by an arrow in the center of the

plane. Light only accumulated onto

this side of the plane. You may flip

this side with the “Flip normal”

checkbox. You may also shift the

lower left corner of the plane, as

well as set the column and row

count and cell size.

14. Run the raytrace again and you’ll

see that the illuminance plane tab

of the results is now populated with

a shaded plot as well as numeric

information. The shaded

illuminance plot is also renderd in

the Model view.