Adam Glaser
@adamkglaser.bsky.social
Developing hardware + software tools for large-scale imaging at the Allen Institute for Neural Dynamics
For really big ExM tissues we made a teflon "drumhead" for one of our open-top systems that was inspired by the FEP flexvat bases for 3D printers. At high mag vibration could definitely be an issue though...
October 31, 2025 at 5:49 PM
For really big ExM tissues we made a teflon "drumhead" for one of our open-top systems that was inspired by the FEP flexvat bases for 3D printers. At high mag vibration could definitely be an issue though...
That is a good data point to know. We hypothesize (no data yet) that aberrations will reduce quickly with expansion factor (RI gradients proportional to density, density gradients will reduce with expansion factor ^3). Whereas the imaging path length only increases linearly with expansion factor.
September 29, 2025 at 2:06 PM
That is a good data point to know. We hypothesize (no data yet) that aberrations will reduce quickly with expansion factor (RI gradients proportional to density, density gradients will reduce with expansion factor ^3). Whereas the imaging path length only increases linearly with expansion factor.
ExA-SPIM2 will provide 35 mm WD with 0.5 NA.
I think there are definitely applications where higher NA is needed. If we designed a 3rd variant, I think aiming for ~0.8 - 0.85 NA (which allows for symmetric 90 deg objectives) with 20 mm WD would be very valuable.
I think there are definitely applications where higher NA is needed. If we designed a 3rd variant, I think aiming for ~0.8 - 0.85 NA (which allows for symmetric 90 deg objectives) with 20 mm WD would be very valuable.
September 29, 2025 at 2:09 AM
ExA-SPIM2 will provide 35 mm WD with 0.5 NA.
I think there are definitely applications where higher NA is needed. If we designed a 3rd variant, I think aiming for ~0.8 - 0.85 NA (which allows for symmetric 90 deg objectives) with 20 mm WD would be very valuable.
I think there are definitely applications where higher NA is needed. If we designed a 3rd variant, I think aiming for ~0.8 - 0.85 NA (which allows for symmetric 90 deg objectives) with 20 mm WD would be very valuable.
"Expansion-assisted" is all about balancing light collection (NA^2) with practicality of engineering lenses with both high NA and long WD. We are collecting data now to quantify this, but we also believe aberrations in ExM will scale with NA^3.
So IMO go as low in NA as specimen brightness allows!
So IMO go as low in NA as specimen brightness allows!
September 29, 2025 at 2:07 AM
"Expansion-assisted" is all about balancing light collection (NA^2) with practicality of engineering lenses with both high NA and long WD. We are collecting data now to quantify this, but we also believe aberrations in ExM will scale with NA^3.
So IMO go as low in NA as specimen brightness allows!
So IMO go as low in NA as specimen brightness allows!
None of the above captures the long WD (35 mm). Perhaps we should introduce a volumetric SBP... that divides the usable WD by either the Rayleigh axial resolution, or an isotropic resolution assumption that divides by the lateral resolution -> would be very high for this lens.
May 20, 2025 at 12:04 AM
None of the above captures the long WD (35 mm). Perhaps we should introduce a volumetric SBP... that divides the usable WD by either the Rayleigh axial resolution, or an isotropic resolution assumption that divides by the lateral resolution -> would be very high for this lens.
Thanks for resolving the numbers.
Agreed, this was the primary motivation for ExA-SPIM in the first place. More pixel parallelization with a larger SBP, either in 2D (global shutter) or even along 1D for rolling shutter (i.e. for ASLM). Also removes some scanning bottlenecks with a low FPS sensor.
Agreed, this was the primary motivation for ExA-SPIM in the first place. More pixel parallelization with a larger SBP, either in 2D (global shutter) or even along 1D for rolling shutter (i.e. for ASLM). Also removes some scanning bottlenecks with a low FPS sensor.
May 20, 2025 at 12:02 AM
Thanks for resolving the numbers.
Agreed, this was the primary motivation for ExA-SPIM in the first place. More pixel parallelization with a larger SBP, either in 2D (global shutter) or even along 1D for rolling shutter (i.e. for ASLM). Also removes some scanning bottlenecks with a low FPS sensor.
Agreed, this was the primary motivation for ExA-SPIM in the first place. More pixel parallelization with a larger SBP, either in 2D (global shutter) or even along 1D for rolling shutter (i.e. for ASLM). Also removes some scanning bottlenecks with a low FPS sensor.
That is right, I used the equation from doi: 10.1117/1.ap.3.4.044001. The required number of samples to fully resolve the signal - also their equation uses 0.5 instead of 0.61. Lens has more information than any current standard camera sensor but potentially could be fully used in the near future.
May 19, 2025 at 10:39 PM
That is right, I used the equation from doi: 10.1117/1.ap.3.4.044001. The required number of samples to fully resolve the signal - also their equation uses 0.5 instead of 0.61. Lens has more information than any current standard camera sensor but potentially could be fully used in the near future.
Totally agree with you 😆 space-bandwidth product > etendue (!)
For 420 - 850 nm light the SBP is 175 - 825 megapixels. Around 500 megapixels at 500 nm.
For 420 - 850 nm light the SBP is 175 - 825 megapixels. Around 500 megapixels at 500 nm.
May 19, 2025 at 8:51 PM
Totally agree with you 😆 space-bandwidth product > etendue (!)
For 420 - 850 nm light the SBP is 175 - 825 megapixels. Around 500 megapixels at 500 nm.
For 420 - 850 nm light the SBP is 175 - 825 megapixels. Around 500 megapixels at 500 nm.
It’s across the board. All grants from all agencies, future ones on pause and current ones also on pause :/
January 28, 2025 at 6:51 PM
It’s across the board. All grants from all agencies, future ones on pause and current ones also on pause :/
Can maybe estimate based on the 35 mm full frame sensor size (36x24 mm). So probably around 1.46 micron pixels? The max rate is 3280 megapixels/sec 🤯
January 28, 2025 at 4:09 AM
Can maybe estimate based on the 35 mm full frame sensor size (36x24 mm). So probably around 1.46 micron pixels? The max rate is 3280 megapixels/sec 🤯