[Effect of IR Pass Filter] I shot the whiteboard with RealSense D435 and D435f.

Intel RealSense D400 series new lineup that calculates depth using stereo vision "Intel RealSense Depth Camera D435fIs a model equipped with IR Pass Filter (infrared filter) of D435.

This time, the user's attention "Filter effectWas verified using the actual D435f machine for specular reflection.

* This article is based on the Optical Filters for Intel RealSense Depth Cameras D400.

Optical Filters for Intel RealSense Depth Cameras D400


Verify the effect of IR Pass Filter!

Previously, in the introduction article of D435f, in the case of bright sunlight (sunlight), glossy table, floor, window glass, etc., where lighting, reflection of sunlight, and reflection are likely to occur, adding a filter is one of the performance factors. I told you that there is a possibility that the department can be improved.

So, this time, I used both the D435 and the newly arrived D435f models to shoot a whiteboard as an example of a glossy substance.Let's compare the actual operation to see how the reflection of light (specular reflection) is recognized.

About the shooting environment

The shooting environment is a relatively bright indoor environment as shown in the photo below.The light from the fluorescent lamp (indoor lighting) on ​​the ceiling was reflected on the whiteboard.

The state of operation is summarized in the following video.Please take a look.

Shoot whiteboards with RealSense D435 and D435f


Comparison of photos taken

Fluorescent lamp reflection verification (default environment: relatively bright room, illuminance: fluorescent lamp)

The whiteboard was placed in front of the camera and angled to reflect the light of the fluorescent lamp.
With the D435f with the IR Pass Filter on the left of the photo, you can see that the light of the fluorescent lamp that was present in the depth data of the D435 on the right of the photo does not have a black spot, and the data can be acquired accurately.


Reflection of outside light (default environment: relatively bright room, illuminance: fluorescent light +Outside light)

During the verification, the outside light from the window was accidentally reflected on the whiteboard.For sudden reflections, depth data was missing even with D435f.The outside light contains more infrared rays than fluorescent lamps, which is probably because the infrared components pass through the IR Pass Filter.

IR frame data acquisition and comparison

I tried to get the IR frame of D435 and D435f. The infrared dot pattern emitted by D435f can be clearly obtained, which is probably due to the effect of the IR Pass Filter.
Depending on the characteristics of the object to be photographed, the D435f may be suitable as in this case, so I hope you find it helpful.


Person who wrote this article :
New Business Development Office Shoji
The date this article was written : 2022.6.24

* This article is based on this verification video.
I think that the video is easier to understand the actual operation, so please see this as well if you like.

Shoot whiteboards with RealSense D435 and D435f


* We can purchase 3D cameras and support feasibility studies such as pre-verification, so please feel free to contact us.