Our Work
Background of our research
To diagnose disruptions in circadian rhythms, it is necessary to measure an individual’s varying photic environment, melatonin secretion, and core body temperature in real-time. However, direct measurement of melatonin secretion and core body temperature using a simple wearable device is not possible. Therefore, we developed a wearable device that indirectly measures these factors in real-time. A specially developed circadian illuminometer, rather than a conventional illuminometer is required to selectively measure the blue light component in the constantly changing light around our eyes.
To enhance circadian rhythms, it is necessary to provide individuals with fully customized phototherapy that irradiates blue light at an appropriate timing and intensity on the circadian clock, until the diagnosed circadian rhythm disturbance is regularized. We have developed a smartphone application with algorithms to control the wearable device using a hybrid device, diagnostic data, and a reset program, allowing personalized diagnosis and restoration of circadian rhythms.
Prior Research
Many processes in the human body, including brain functions, are regulated over a 24-hour cycle, and there is a strong correlation between disrupted circadian rhythms (e.g., sleep-wake cycles) and central nervous system disorders. Brain disorders, such as autism, depression, and Parkinson’s disease, usually occur at specific stages of life, highlighting the importance of circadian rhythms at various life stages for regulating processes that may influence the development of these disorders. Here, we describe the circadian disruptions observed in various brain disorders throughout an individual’s life and emphasize new evidence suggesting the impact of these disruptions on the brain.
Rhythms of life: circadian disruption and brain disorders across the lifespan
t is well-known that the process of light entering the retina regulates the timing of our circadian system. Disrupting the regular 24-hour pattern of light and darkness can notably affect our health and well-being. Various modern diseases, ranging from sleep disorders to cancer, are associated with circadian disruptions caused by light.
Research on light-induced circadian disruptions requires a new definition of light (and darkness). Here, we explain the significance of developing a new definition of circadian light that can be used to contrast light as a stimulus to the human visual system to ultimately enhance health and well-being.
The circadian system regulates physiological and behavioral processes. There is no doubt that the circadian system contributes to health and disease, and there is an increasing need for clear concepts when explaining the influence of the circadian system and its consequences. The objectives of this review are to provide an overview of the terminology used to describe disruptions in the circadian system, discuss proposed quantifications of disruptions in experimental and observational settings with a focus on human research, and highlight the limitations and challenges of currently available tools.
A brief review of photometry, colorimetry, and brightness perception is presented as the basis for discussions on circadian light. Finally, the procedures for calculating Circadian Light (CLA) and Circadian Stimulus (CS) based on publicly available mathematical models of the circadian light in humans are presented with examples.
A brief review of photometry, colorimetry, and brightness perception is presented as the basis for discussions on circadian light. Finally, the procedures for calculating CLA and CS based on publicly available mathematical models of the circadian light in humans are presented with examples.
The user-customized circadian rhythm diagnosis and enhancement platform was created as follows:
The circadian mechanism is implemented through three key technological components.
People live in different environments. Diagnosing individual circadian rhythms requires measuring real-time melatonin hormone secretion and core body temperature, which is practically challenging. We have developed a simple wearable device called the Circadian Sensor to determine individuals’ light exposure. We have also developed an algorithm that controls the phototherapy program after measuring melatonin and core body temperature by analyzing individuals’ light environment data collected using the above sensor. With this algorithm incorporated, the [Circadian Application] regulates the phototherapy program of the [Circadian Lamp].
Circadian Rhythm
Diagnosis and Enhancement Platform

Collecting Light Environment Data by Circadian Sensor
Measuring Melatonin Suppression Wavelength Spectrum
CirKadian illuminometer
A wearable device that measures the blue light component around the eyes selectively and in real-time in each individual Collecting Light Environment Data by Circadian Sensor
Measuring Melatonin Suppression Wavelength Spectrum

Using the measured data
and the circadian algorithm,
melatonin, and core body temperature,
which are difficult to measure directly,
are derived.
CirKadian application
A smartphone application equipped with an algorithm responsible for performing the personalized phototherapy program that applies blue light to the circadian clock at the appropriate timing and intensity to restore disrupted circadian rhythms caused by light pollution, until the diagnosed circadian rhythm disruption is normalized.

The Circadian Lamp provides
blue light LED phototherapy
and restores circadian rhythm.
CirKadian lamp
A device that provides blue light LED therapy.
The Circadian Lamp
provides blue light LED phototherapy
and restores circadian rhythm.
Get to know us
We have developed healthcare technology to diagnose and restore circadian rhythm disruptions. Disruptions in circadian rhythms lead to issues such as insomnia, depression, stress, obesity, and accelerated aging, which can weaken the immune system and increase the chances of incidence of severe diseases such as cancer and Alzheimer’s.

01
Circadian Rhythm and Melatonin Rhythm
Humans naturally have a normal circadian rhythm.
02
Modern Lifestyle and Light Pollution
Modern people use computers under artificial indoor lighting during the daytime and use smartphones until bedtime, exposing themselves to serious artificial light environments.


03
The Impact of Light Pollution
This leads to disrupted circadian rhythms and decreased amplitude of the rhythm.
04
Circadian Rhythm Disruption and Healthcare
Circadian rhythm disruption leads to problems such as insomnia, depression, stress, obesity, and accelerated aging. In particular, these issues can weaken the immune system and increase the chances of incidence of severe diseases such as cancer and Alzheimer’s, highlighting the need for circadian rhythm restoration.

History
2016-2018
Preparation and Incorporation
- Established Circadian Corporation (Dec ’18)
- Selected as an excellent institution for IP R&D (Nov ’17)
- Received the Director’s Award from the Korea Institute of Patent Strategy and Development (Nov ’17)
- Selected as the Leading Research Center Project (ERC) by the Ministry of Science and ICT (June ’16)
- Obtained a total funding of 14 billion KRW over 7 years with 2 billion annually
- Established the Circadian ICT Research Center within Kookmin University, a lead agency (July ’16)
2019
- Exhibited Circadian Glasses at Korea International Medical & Hospital Equipment Show (Mar ’19)
- Entered Circadian Glasses in the Good Design Award (Apr–May ’19)
- Achieved the highest evaluation in the ERC Phase 1 (Nov ’19)
2020
- Invited to give a lecture representing the Circadian Rhythm Healthcare technology by CEO Kim Dae-Hwan at the largest international conference, SID (Aug ’20)
- Circadian Glasses won the Winner award at the Korea Design Exhibition (Dec ’20)
2021-2022
- Obtained ISO9001 and 14001 certifications (May ’21)
- Completed the production and testing of prototype devices: Circadian Illuminometer, Lamp, and Glasses
- Verified the functionality, effectiveness, and marketability of the products through clinical research
- Secured key IP and completed patent infringement analysis