Optogenetics Solutions: LEDs, Lasers & Rotary Joints

Optogenetics Solutions

Build a complete optogenetics system to activate or inhibite neural circuits. At Doric Lenses, we offer a comprehensive range of light sources for optogenetics, all developed and manufactured in-house. In addition, we provide a ecosystem of optical components such as light splitters, combiners, rotary joints/commutators, patch cords, and cannulas—including components that combine optogenetics with other modalities (behavior, fiber photometry, Doric Miniscope, fluidics, electrophysiology, etc.).

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The technique

Optogenetics is a groundbreaking technique that provides real-time, optical control of neuronal activity.

The optogenetics approaches requires expressing opsins, light-sensitive ion channels or pumps, in a specific neuronal population. For chronic experiments, a fiber-optic cannula is surgically implanted above the target region to deliver a specific wavelength of light, activating or inhibiting the opsin-expressing cells. For example, blue light activates opsins like Channelrhodopsin (ChR2), while yellow or red light targets opsins such as NpHR or Jaws. For a list of available opsins, see the OPSIN APPLICATION NOTE.

Build Your Optogenetics System - Configure a complete system based on your opsin, wavelength, number of animals, stimulation sites, and experimental modality.

Customize your System

Light Sources

Rotary Joints / Commutators

Splitters

Combiners

Fiber-optic Patch Cord

Cannula

Software

COMBINE WITH...

Optogenetic illumination

Light Sources

Choosing the right light source is one of the most important steps when designing an optogenetics experiment.

The optimal light sources depend on the:

Opsin's excitation wavelength (nm)
Opsin's intensity requirements (mW/mm²),
Optical fiber diameter or size of the target area(s),
Number of regions-of-interest and/or animals excited simultaneously,
Anticipated transmission through the system (taking into account splitting, rotary joint, etc.)

There are several broad categories of Light Sources: (1) LEDs (regular, DazzLED and wireless, etc.), (2) Laser Diodes, and (3) LISER™.

Each light source has different optical properties (including emitter size, coherence, numerical aperture (NA), max power, max intensity, etc.) that makes it more of less optimized for different applications.

	Connectorized LED	★LISER™ Light Source	Connectorized Laser Diode Modules	DazzLED	Wireless Optogenetics Headstage
Recommended Applications	Affordable choice to illuminate larger brain regions (400 µm +)	Multi-colour illumination, including 590 nm at high intensity	Illuminate small brain regions (< 200 µm) with high intensity	High-throughput illumination for multi-site and/or multi-animal	Cable-free illumination for freely-moving and/or interacting animals
Emitter Size	1 mm²	1 mm²	0.00005 mm² (50 µm²)	9 mm²	1 mm²
Optimal Fiber Diameter	200 µm - 1000 µm	200 µm - 1000 µm	50 µm - 200 µm	200 µm - 3000 µm	200 µm or 400 µm
Optimal Fiber NA	High NA (0.57, 0.63)	High NA (0.57, 0.63)	Low NA (0.22, 0.37)	High NA (0.37, 0.57)	High NA (0.66)
Excitation Intensity	Moderate	High (especially at 560-590 nm)	Very High	Moderate	Moderate
Light coherence	Incoherent	Incoherent	Coherent (speckle)	Incoherent	Incoherent
Available wavelength	365 nm - 900 nm (27 options)	Swap between 525, 559, 582, 593, 612 nm using bandpass filter. Add an additional blue light source.	405, 450, 473, 488, 520, 638 nm	435, 450, 520, 620 nm	465, 528, 634 nm
Max sites per light source	Up to 4 x 400um with SBP	Up to 4 x 400um with SBP	Up to 4 x 400um with DMC	Up to 100 x 400µm fibers using LLG and BBP	N/A
Cost	$	$$$	$	$$	$

LEDs vs Lasers

These two types of light sources differ in terms of emitter size, maximum intensity, maximum illumination area and recommend fiber diameter and NA.

LEDs

LEDs are among the most commonly used light sources in optogenetics, suitable for experiments stimulating large regions-of-interest (with 400 µm - 1mm diameter) at moderate light intensities. Their large emitter, inherent safety, reliability, and affordability make them a preferred option across a variety of experimental designs. Another advantage compared to laser diodes are their illumination uniformity (devoid of speckle).

At Doric Lenses, we offer a wide range of CLED wavelengths in the near-UV (350-400 nm), visible (400-700 nm) and near IR range (700-1100 nm) for standard optogenetic applications.

Laser Diodes

Laser diodes are high-brightness light sources with small emitter ideal for optogenetic experiments requiring high intensity of light in small regions-of-interest (< 200um). Their narrow beam profile and monochromatic light output make lasers ideal for illumination through small-diameter patch cords (typically 50–200 µm) and are a great solution when precise spatial targeting is required.

Unlike DPSS laser, laser diodes are not only more affordable, but also offer much faster response times, enabling rapid modulation of laser intensity and precise control of stimulation timing. This makes them particularly well suited for high-speed optogenetic applications, where millisecond-scale temporal precision is essential.

What is the best light source for High-power Yellow (590 nm) optogenetics?

LISER™ (Laser-Induced Spontaneous Emission of Radiation) is an advanced light source providing high-intensity, broad-spectrum illumination. The system uses a laser pumped Ce:YAG (cerium-doped yttrium aluminum garnet) crystal, which emits a continuous spectrum from yellow to red (500–650 nm).

This light source provides exceptionally high optical power (> 85 mW full spectrum in a 200 µm NA 0.57 fiber) in a spectral range that is difficult to achieve with standard LEDs or laser diodes, particularly around 590 nm, optimal for activating inhibitory opsins such as NpHR and Jaws. In addition to its broad-spectrum output, LISER™ includes an integrated blue excitation source (laser or LED), making it a versatile, all-in-one solution capable of supporting both excitatory and inhibitory optogenetics simultaneously.

The LISER™ also includes its own internal drivers, allowing independent control of two wavelength channels in the same brain region (e.g., 450 nm + 590 nm).

Key Features

Full-Spectrum Coverage: Simultaneously delivers blue excitation plus tunable yellow-red wavelengths using interchangeable optical filters (e.g., 525, 559, 582, 593, 612 nm).
High Power: Ideal for experiments requiring intense illumination, including bilateral and/or large-area stimulation.
Supports Large-Core Patch Cords: Optimized for 200–400 µm core diameters, enabling uniform, wide-area stimulation for illumination of larger brain regions.

What Is the Best Light Source for Multi-Animal Optogenetics?

For multi-animal or multi-site optogenetics experiments, DazzLED is the optimal solution. This light source can be combined with the DazzLED Fiber Converter and Bundle Branching Fiber Optic Patch Cords to deliver high-power stimulation across many fibers simultaneously.

This configuration enables scalable, high-throughput photostimulation of up to 20 fibers with 400 µm diameter cores or up to 100 fibers with 200 µm diameter cores, making it well suited for parallel optogenetic experiments, multi-region stimulation, and large cohort studies.

What light source can be combined into the light path of a microscope?

DazzLED can be seamlessly integrated into most fluorescence microscopes through the illumination path, enabling simultaneous wide-field imaging and high-power optogenetics. Its broad, uniform illumination is ideal for activating large neuronal populations or extended regions of tissue. Beyond optogenetics, DazzLED provides a versatile excitation source for applications including photouncaging, photoconversion, photoswitching, and activation of other light-responsive molecules across large fields of view.

How can you control the light sources?

To operate Doric LED and Laser diode modules, a dedicated light source driver is required. The driver can either come as a standalone device, or can integrate the lighh source (fiber-light sources, FLS).

Integrated Driver Units (FLS): In this setup, each driver channel has a built-in LED or laser, offering a compact and user-friendly solution.
Modular Driver Setup (Driver): The LED/laser remains separate from the driver, provides flexibility to switch between different wavelengths.

The driver can be operated in 1) standalone, 2) external modes (Analog or TTL), or 3) program sequences using free Doric Neuroscience Studio (DNS) software. In DNS, users can define a wide range of light stimulation patterns including continuous wave output, square pulse trains, sine waveforms, and custom waveforms.

Watch the tutorial video for step-by-step guidance on using LED drivers.

All light source drivers can be triggered by external digital signals, unlocking the ability to do closed-loop experiments, where behaviors (lever press, nose poke, beam break, etc.) trigger the optogenetic stimulation. As such, DNS support complex triggering modes to pause, restart, and continue a stimulation pattern, as described in the following tutorial video.

NOTE:

LED drivers are only compatible with LEDs, and LD drivers only with lasers.
LISER come with integrated driver.

Optogenetics during Freely-moving behaviors

Rotary Joints / Commutators

Prevent optical fibers and cables from twisting and disrupting naturalistic animal behaviors during freely-moving experiments.

Rotary joints

Optical

Prevent optical fibers from twisting during optogenetics and/or fiber photometry experiments.

NOTE: Pigtailed rotary joints are required when combining optogenetics with fiber photometry.

1x1 Fiber-optic Rotary Joints - Connectorized

Pigtailed 1x1 Fiber-optic Rotary Joint Gen.2

1x2 Fiber-optic Rotary Joints - Intensity Division

2x2 Fiber-optic Rotary Joint

2x2 Pigtailed Fiber-optic Rotary Joint

Assisted 2x2 Fiber-optic Rotary Joint

Assisted 2x2 Pigtailed Fiber-optic Rotary Joint

Defining the 1x1, 1x2 and 2x2 rotary joint nomenclature

# x # refers to the division of optical channels above and below the rotary joint.

1x1 = single optical channel
1x2 = one optical channel that splits into two for bilateral optogenetics
2x2 two separate optical channels for independent stimulation. Often used when combining fiber photometry and optogenetics.

Can electrical rotary joint be upgraded to opto-electric?

Yes, but only for AERJ_24 and AERJ_24_RFMC. You can purchase Upgrade Kits to add an optical channel through the hollow central canal of the electrical rotary joint.

Why are "pigtailed" rotary joint critical for fiber photometry?

Pigtailed rotary joint refer to built-in fibers within the rotary joint that cannot be detached.

These ensure the top and bottom fibers are well-aligned and significantly reduce the fluorescence fluctuations that occur during rotations in fiber photometry recordings.

***WARNING: Using non-pigtailed rotary joint can results in large motion artifacts in the fiber photometry signal.***

What is the difference between "passive" and "assisted" rotary joints?

Passive rotary joint refer to non-motorized commutators that rely on the animals own force for rotation. The force required depends on the rotary joint and the internal friction of the components. For a single optic-fiber on its own, the friction is quite low and no motorized assistance is required.

Assisted rotary joints are rotary joints with a motorized rotational component. This motorized approach is generally required when more than one optic fiber and/or electrical cables are added to the system. When there are multiple component, the friction during rotation becomes significant, requiring strong start up torque. Often times this start up force is too large for small animals, like mice, and impedes naturalistic behaviors. Thus, motorized assistance ensure normal animal behavior.

Splitters

Divide the light from a single light source into multiple fibers for bilateral, multi-site and/or multi-animal experiments. The optimal splitter depends on the type of light source (LED, LISER or laser diode), the intensity requirements and the size of the region-of-interest.

IMPORTANT: Matching the light source to the appropriate splitter is important. The splitting efficiency and resulting maximum power can be drastically affected if the wrong type of splitter is used.

Splitting Branching Patch Cords (SBP)

Divide the light from one large optic fiber into 2-4 smaller optic fibers.

Split in up to 4 outputs
Recommended for LED or LISER™
Compatible with high & low NA
Simple and low-cost

Doric Mini Cube - intensity division

Divide the intensity of light via a series of dichroic mirrors.

Split up to 4 outputs
Recommended for laser diodes
Optimized for low NA fibers
Higher transmission

1x2 Fiber-optic Rotary Joint

Divide the light for bilateral / dual-site stimulation on a freely-moving animal.

Limited to 2 outputs
Recommended for laser diodes
Optimized for low NA fibers
Splitter integrated within rotary joint

Combiners

Deliver multiple wavelengths of light to the same target region using a single fiber-optic patch cord.

All combiners include optics (dichroic mirrors) to combine the light from multiple light sources into a single optic fiber. Some combiners also integrate light sources (and sometime their drivers) directly within the device for a compact form factor, and/or are mounted directly onto a rotary joints to reduce the number of connections within the system and conserve excitation power.

Doric Mini Cube

Connect 2-4 light sources to this device to combine the inputs into a single output.

Combine up to 4 colours in ONE fiber
Compatible with ALL light sources
Ideal for low & high NA fibers
Compatible with LEDs & Laser Diodes

Combined LEDs

Choose up to four light sources to integrate with the device and the dichroic mirror for a compact form factor.

Integrate up to 4 LEDs into 1 fiber
Ideal for high NA fibers (0.57, 0.63)

Combined LEDs with Rotary Joint

Combine LEDs & dichroic mirror(s) within the rotary joint to maximum excitation power.

Integrate up to 4 LEDs into 1 fiber
Ideal for high NA fibers (0.57, 0.63)
For freely-moving animals

★LISER™ Light Source

Multi-colored light source (and integrated driver) with a single fiber-optic output.

Combine blue & green/yellow/red
High-intensity illumination @ 590 nm
Swap filters to select wavelength
Ideal for high NA fibers

Fiber-optic Patch Cords

Deliver optogenetic illumination in one, two of more regions-of-interests / animals. Note that the recommended material, diameter and numerical apperture differs depending on the light source and experimental requirements.

Mono Fiber-Optic Patch Cord

Simplest fiber optic for basic single fiber optogenetic applications. Comes in a variety of ferrules types compatible with all Doric Mono-fiber optic cannulas.

Dual Fiber-Optic Patch Cord

Maintains two separate optical channel on the input and output. Compatible with Dual-fiber cannula, for bilateral or dual-site stimulation.

Bundle-Branching Patch Cord

Contains multiple fibers in a single connector that branch into multiple mono fiber connections. Recommend for DazzLED.

Splitting-Branching Patch Cord

Divides the light from a single fiber into 2-4 outputs for bilateral / multi-site stimulation using a single light source.

Recommend patch cord for LEDs / LISER™

For an LEDs, use a large-core, high-NA patch cord, typically 400–600 µm core with NA 0.57 (silica/polymer) or 0.63 (plastic), to maximize light collection and coupling efficiency.

Recommended patch cord for laser diodes

Use a small-core, low-NA patch cord to match the laser diode output, typically 50–200 µm core with NA 0.22–0.37. This improves coupling efficiency and limits beam divergence compared with a large-core, high-NA fiber.

For Doric laser diodes, it is important to use FCA connector (FC/APC with angle) to prevent back reflection that can result in illumination instabilities and ripples, or even damage the laser over time.

Why is the numerical apperture important?

Numerical aperture (NA) describes the range of angles a fiber can accept and emit light.

In optogenetics, higher NA generally improves light collection and delivers light over a wider angle, while lower NA produces a narrower beam that tends to penetrate with higher depth.

Matching the NA to the light source helps maximize coupling efficiency.

Chronic Brain implants

Fiber-optic Cannulas

Cannulas

Optical

Chronic fiber-optic implant for:

Single-site
Dual site / bilateral
Multi-site

Mono Fiber-optic Cannula

Dual Fiber-optic Cannula

Fiber-optic Cannula Array

High-density Fiber-optic Cannula

How to choose the right fiber core diameter and NA of the cannula?

To optimize the light delivery into biological tissue, the optical fiber core diameter and numerical aperture have to be carefully selected. The larger optical fiber core diameter brings light to a larger area while making more damage to the tissue. A higher numerical aperture will spread light to a larger cone angle and will transmit more power when working with an incoherent light source as LED, but high numerical aperture optical fibers are in general not as robust as lower numerical aperture version due to difference in fiber construction.

Generally, its a good rule of thumb to match the NA and diameter of the cannula to the NA of the patch cord/rotary joint.

For example, match a 0.22NA, 200 um diameter fiber-optic patch cord with a 0.22NA, 200um diameter fiber-optic cannula. However, while some materials (silica/polymer) have properties like flexibility that are ideal for patch cords, but are NOT well suited for cannula implants. For instance, using a cannula with a fiber with a curvature during the implantation surgery is not ideal, as it can potentially reduce successful targeting during stereotactic surgeries.

For high NA (LEDs/LISER™)

We recommend pairing 0.57/0.63 patch cords with 0.66 borosilicate cannulas. In this case, the smallest NA of all the optical component is the effective NA of the system.

For low NA (laser diodes)

We recommend matching the NA. 0.22 -> 0.22 and 0.37 -> 0.37

How to choose the right cannula ferrule/connector?

The choice of optical fiber connector, or cannula receptacle, depends on the type of experiment and selected animal model.

The simplest and the most common connection is the ferrule/sleeve with 1.25 or 2.5 mm diameter. Because of the smallest footprint and relatively good connection. However, the connecting requires some skill and can
exert non-negligible pressure on the animal. Alternative solutions are offered, for example, if the experiment requires multiple connections and disconnections, the magnetic connector could be a solution. If the experiment involves larger and more active animals, the M3 screw-type connector provides a secure and reliable connection.

How to choose the cannula probe tip?

The light propagation into brain tissue will vary with the optical fiber type and the light source parameters. It can be visualized in this Application Note (the French version is available here).

The shape of the optical fiber tip may help to optimize the optogenetics illumination distribution or minimize the collateral tissue damage.

Here is a short list of available fiber tip:

Cleaved: A cleaved tip is the most economical solution, but not very precise or repeatable.
Flat Tip (FLT): Flat tip termination provides a polished fiber tip and accurate protrusion length. When implanted in the brain it delivers a narrow cone of light in front of the fiber.
Angle (A): Angle termination involves the polishing of the fiber tip at a chosen angle for easier tissue penetration. When immersed into a high refractive index and highly scattering biological tissues, the light intensity distribution is almost the same as the flat tip.
Cone (C): Cone termination involves the polishing of the fiber tip into a cone of outer angle, for easier tissue penetration. When immersed into a high refractive index and highly scattering biological tissues, the light intensity distribution is almost the same as the flat tip.
Angle Mirror (MA): Angle mirror termination involves the polishing of the fiber tip at a chosen angle, typically 45 degrees with a mirror coating added on the polished surface to redirect light sideways.
Tapered: Tapered fibers are pulled to give a sharp and narrow tip that facilitates penetration into tissue and reduces damage. Light output from the tapered tip is escaping all along the taper, as light refraction angle exceeds critical angle and is no more guided along the fiber. This can be used to illuminate a larger volume and avoid high light intensity localized at the fiber tip.
Diffuser (DFL): Diffuser termination involves the addition of a diffusing material at the tip of the fiber. This increases the angular spread of light output from fiber compared to the relatively small output beam angle of a flat tip and helps to illuminate more neurons of interest for optogenetics or electrophysiology experiments.

Beyond optogenetics

Combine your system with...

Behavior

Study the neural circuits underlying functions like decision making, memory formation, social interactions, sleep, etc.

Record and synchronize videos, digital inputs/outputs for stimuli timing or behavior measures.

Behavior & Bundle Photometry Console

Behavior Camera

CamLoop

Manual TTL Pulser

danse™

FREE data acquisition software

Doric Neuroscience Studio

Create Stimulation Patterns

Define the frequency, periods, delays, pulse duration and shapes with modes including continuous wave, square pulses, sine waveforms, and complex.

Synchronize with Behavior

Visualize, synchronize and record optogenetics sequence, behavior video and TTL pulses in a single interface and data file.

Closed-loop optogenetics

Define triggered modes, where external digital signals arising from behaviors (lever press, nose poke, etc.) trigger the stimulation.

Combine with other Modalities

One software for fiber photometry, miniscope, optogenetics, behavior and electrophysiology recordings.

danse™ Data Analysis Software

Create an experiment project

Organize fiber photometry, miniscope & behavior data according to YOUR experimental design.

Learn more

danse™ Data Analysis Software

Import behavior data

Easily align and sychronize non-Doric csv/excel & video data to your fiber photometry/miniscope experiment.

Learn more

danse™ Data Analysis Software

Build analysis pipelines

Chain multiple operations together and run them over ALL of your animal data files.

Learn more

danse™ Data Analysis Software

Generate Group Analysis Plots

With a few clicks of a button, pool data from multiple animals according to YOUR experimental design.

Learn more

References

Laing et al. "Repetitive grooming behavior following aversive stimulus coincides with a decrease in anterior hypothalamic area activity" eNeuro, 2025.
Kosugi et al. "Bidirectional optogenetic modulation of peripheral sensory nerve activity: Induction vs. suppression through channelrhodopsin and halorhodopsin" iScience, 2025.
Williams et al. "Interpeduncular GABAergic neuron function controls threat processing and innate defensive adaptive learning" Molecular Psychiatry, 2025.

See all publications