Includes extended extinction coefficients, a new scatter model, updated blood vessel modeling, and added capability
Just Released: BIO Toolkit 25.02.01
October 16, 2025 – Tucson, AZ – Breault Research Organization is pleased to announce the release of BIO Toolkit 25.02.01. BIO Toolkit is an add-in to the ASAP optical simulation environment. It includes two modules, RSM (Realistic Skin Model) and AHEM (Advanced Human Eye Model).
BIO Toolkit 25.02.01 focuses on the RSM module and includes extended extinction coefficients, a new scatter model, updated blood vessel modeling, and added capability.
Realistic Skin Model
RSM provides an accurate, quick, and easy tool for simulating human skin to analyze the interaction of a wide range of optical sources with skin and other tissues. Users can easily create customized skin models by entering information into dialog windows. The skin sample size, model wavelength, and source specifications can each be adjusted to adapt the model to any scenario.
RSM utilizes published data of the extinction coefficients for various chromophores in human skin, including water, eumelanin, pheomelanin, oxygenated and deoxygenated hemoglobin, beta carotene, and bilirubin. Current capabilities model the stratum corneum, epidermis, dermis (both papillary and reticular), and hypodermis.
Extended Extinction Coefficients
BIO Toolkit 25.02.01 expands the extended extinction coefficients to 1700 nm; an extension of 700 nm in the near infrared.
Based on compiled data by Steve Jacques and Scott Prahl at the Oregon Medical Laser Center, the extinction coefficients of each chromophore from 250-1700 nm are included in RSM. Each layer of skin is given a bulk absorption and scatter model based on the concentration of each chromophore. These models use the Henyey-Greenstein scattering approximation to be used in the Monte Carlo raytrace.
New Scatter Model
When selecting skin layers, users can now choose to model the stratum corneum, epidermis, dermis, and hypodermis. Unique to each layer, a new scatter model is created for optimizing the analysis completed and shown. This allows for the modeling of a broader range of tissue conditions.
Updated Blood Vessel Modeling
RSM is now capable of modeling human hair and blood vessels in the skin. Both models are extensive enough to simulate how both behave optically in human skin.
Added Capability
BIO Toolkit 25.02.01 now allows users to model hair and a two-layer dermis/dermal papillae, simultaneously. When selecting skin layers, users can now choose to model the stratum corneum, epidermis, dermis, and hypodermis. The dermis can then be split into the papillary and reticular dermis if desired, or a single-layer bulk approximation of the dermis can be used. If a two-layer dermis model is chosen, dermal papillae modeling can then be selected to increase the accuracy of the skin model.
For more information about BIO Toolkit, contact sales@breault.com
About BRO
Breault Research Organization (BRO) is an optical engineering and software firm founded by Dr. Robert Breault and headquartered in Tucson, Arizona. BRO provides optical software products – ASAP, APEX and ReflectorCAD – and training courses that help optical scientists and engineers turn creative visions into working prototypes. BRO is regarded throughout the industry for its work in space instrumentation and beyond state-of-the-art projects for top government labs, research institutions, and Fortune 500 companies.