Aggregation of flying insects such as gypsy moths at commercial light sources in summer not only has an aesthetically negative impact on public facilities but also permits the establishment of new insect populations there from the next year. Although energy-efficient light traps equipped with light-emitting diodes (LEDs) have recently been used for controlling pest insects in agriculture, there are very few maintenance-free light traps that are available on the market. Based on the results of field surveys, we fabricated a prototype light trap in which the preferences of insects for light irradiation angle and wavelength are implemented. Field experiments revealed that flying moths were attracted more to light with a narrow irradiation angle than to light with a wide irradiation angle. Moreover, there was a tendency for fewer moths to be collected when fluorescent paint was applied to the surface of the flight-interception board, indicating that a high contrast made by illumination and the background is preferred by flying moths. Taken together with our previous results, we found that the moth catch was influenced more by modification of the light design than by change in visible light wavelengths. A semi-portable light trap, named the “Kurihara trap” after the primary contributor to its development, is made of light-weight plastic and is driven by solar power. This light trap is omnidirectional and maintenance-free and is therefore suitable for deployment in the backyards of rest areas as well as at houses for long-term macromoth sampling.