The aim was to develop and demonstrate a space telescope suitable for automatic operation with optical resolution better than 5 m, to be installed on a satellite approximately 50 cm in size.

In addition to considering launch vibration resistance and space radiation resistance in orbit, it was necessary to develop a technology (athermal and apochromatic) that could effectively eliminate chromatic aberration and maintain focus regardless of environmental changes in orbit.

By combining the effects of lens shape deformation, refractive index changes, and barrel expansion and contraction caused by environmental temperature fluctuations, it has “athermal” characteristics that enable it to maintain focus on the detector at all times. Thus, there is no need to adjust the focus of the telescope while it is in orbit. This feature has greatly contributed to the realization of automatic operation of satellite observation systems.

Even with a small telescope, high spatial resolution can be expected if the satellite's orbital altitude is low. On the other hand, when the orbital altitude is low, the satellite's orbital velocity is fast, which makes image blurring more likely to occur and impairs spatial resolution. In addition, telescopes flying at super low altitudes (around 300 km) require not only the physical modifications required for conventional telescopes, but also special chemical modifications to protect them from reactive oxygen atoms in the upper atmosphere. It was necessary to develop a telescope that took these factors into consideration.

• ・Primary mirror diameter is 20mm, area sensor.
• ・It consists of a reflecting telescope section comprising a primary and secondary mirror, and a refracting lens system to compensate for the flatness of the image plane. The effect of chromatic aberration is extremely slight and can be considered equivalent to a pure reflecting system.
• ・The focus mechanism can be omitted because it has athermal characteristics that prevent changes in focus position even when the environmental temperature changes.
• ・We applied TDI (Time Delay Integration) technology, which compensates for image blur by transferring electric charges on a CCD in synchronization with the satellite's orbital motion, to area sensors. This enables high S/N snapshot imaging even when the ground observation object is illuminated at an oblique angle.
• ・Special technology has been introduced to prevent deterioration of camera performance even in the highly oxidizing environment of super low altitude orbits, where the density of atomic oxygen is approximately 1,000 times higher than in low Earth orbit.

The origin of humankind and its relationship to carbon compounds and hydrated minerals brought from outside the solar system are being debated.
In the Hayabusa 2 Project, a mission to collect samples from an asteroid approaching Earth's orbit, identifying the touchdown location was critical to the mission's success.

• ・Spectral camera in the SWIR (Short Wave InfraRed: wavelength 1 - 3.5μm).
• ・A transmissive grating was adopted to make the device more compact.
• ・To suppress thermal background noise, it is designed and manufactured to operate in a low-temperature environment (190K).

The reason why the temperature of the upper atmosphere of the sun exceeds 1 million degrees Celsius, even though the surface temperature of the sun is 6,000 degrees Celsius, has long been a mystery in solar physics. In order to maximize the performance of the solar telescope developed to solve this mystery, it was essential to integrate a space observation system using a collimator lens.

Fully color corrected optical system that achieves six-color correction across a wide wavelength range from 450 nm to 900 nm. The thermal aberration characteristics are minimal, at 1e-6 order/K per unit focal length.

Development of a system that can efficiently and compactly achieve scientific results in agriculture, marine science, and other fields was required.

Snapshot sensors, which are compatible with 50 kg class satellites and achieve both high spatial resolution and wavelength resolution, are also advantageous in terms of relaxing the attitude stability requirements for satellites.

We have successfully achieved multi-wavelength imaging with a ground resolution of 5 m. There is no other spectral imaging sensor with more than 400 narrow-band bands.

The Earth's surface can be broadly divided into land areas and water areas, and the reflectance of sunlight and its wavelength dependence can be found in correspondence with the polarization components of reflected light. By precisely observing this, it becomes possible to accurately identify the characteristics of the observed object. This device was developed to demonstrate this.

This is a spectroscopic polarizing telescope that consists of three spectroscopic cameras with identical characteristics, arranged in a 120° symmetrical configuration to detect polarization, and configured to take images simultaneously as a set.

The first unit was installed on Institute of Science Tokyo's (formerly Tokyo Institute of Technology) “HIBARA” Satellite and has been functioning normally since its launch in 2021 until now (2025).

• ・Hand-sized compact design, low power consumption, high accuracy.
• ・STT with arcsecond accuracy proven in orbit (world's highest level for this size).
• ・The combination of special food design and optical design results in a small sun/Earth avoidance angle and high layout flexibility for satellite buses.
• ・Developed and implemented a rational control command system.

The optical sensors used in space telescopes are constantly deteriorating due to radiation damage in orbit. This STT provided various basic information on the extent of this deterioration and ways to recover from it.